Seattle–Tacoma International Airport

A shared public airport was proposed by the Port of Seattle and Port of Tacoma in the late 1920s, but deferred plans after the legality of public ports operating such facilities was rejected by the state attorney general in a published opinion. The state legislature authorized municipal corporations such as public ports to establish aviation facilities in 1941.{{cite web |last=Caldbick |first=John |date=August 2, 2010 |title=Airports Owned by Washington's Public Port Districts |url=https://dev.historylink.org/File/9498 |work=HistoryLink |accessdate=July 1, 2024 |archive-date=July 2, 2024 |archive-url=https://web.archive.org/web/20240702053302/https://dev.historylink.org/File/9498 |url-status=live }} The Port of Seattle accepted a $1 million grant (equivalent to ${{Format price|{{Inflation|US-GDP|1000000|1942}}}} in {{Inflation-year|US-GDP}} dollars){{inflation-fn|US-GDP}} from the Civil Aeronautics Administration in March 1942 to construct a new airport to serve the Seattle area after the U.S. military took control of Boeing Field during World War II. A site on U.S. Route 99 near Bow Lake south of Seattle was chosen at the end of the month ahead of another candidate near Lake Sammamish that was considered too close to the Cascade Range. The City of Tacoma provided $100,000 towards the airport's construction costs as part of a deal for the Bow Lake site, centered around an existing private airfield plagued by heavy fog.{{cite web |last=Crowley |first=Walt |author-link=Walt Crowley |date=April 2, 1999 |title=Sea-Tac International Airport: Part 1 – Founding |url=https://historylink.org/File/1004 |work=HistoryLink |access-date=August 3, 2020 |archive-date=January 22, 2021 |archive-url=https://web.archive.org/web/20210122073649/https://historylink.org/File/1004 |url-status=live }} Construction of the airport, which was named Seattle–Tacoma in recognition of Tacoma's contribution, began with a groundbreaking ceremony on January 2, 1943.{{cite news |date=January 2, 1943 |title=Break Ground for Airport |page=1 |work=The Seattle Star |url=https://www.newspapers.com/article/the-seattle-star-break-ground-for-airpor/148029847/ |via=Newspapers.com |accessdate=May 24, 2024}}{{cite news |date=July 4, 2004 |title=History of Seattle-Tacoma International Airport |url=https://archive.seattletimes.com/archive/?date=20040704&slug=seatachistory04 |work=The Seattle Times |accessdate=May 24, 2024 |archive-date=May 25, 2024 |archive-url=https://web.archive.org/web/20240525062052/https://archive.seattletimes.com/archive/?date=20040704&slug=seatachistory04 |url-status=live }}

The project was originally estimated to cost $1.7 million (equivalent to ${{Format price|{{Inflation|US-GDP|1700000|1944}}}} in {{Inflation-year|US-GDP}} dollars),{{inflation-fn|US-GDP}} but the sandy soil conditions drove the final construction price to over $4.2 million (equivalent to ${{Format price|{{Inflation|US-GDP|4200000|1944}}}} in {{Inflation-year|US-GDP}} dollars).{{inflation-fn|US-GDP}} The airport's plateau was formed through {{convert|6.5|e6cuyd|m3}} of excavated earth. A proposal to rename the airport for Boeing president Philip G. Johnson shortly after his death in September 1944 was rejected by Port of Seattle commissioners due to the objections of Tacoma. The first ceremonial landing at Seattle–Tacoma Airport was made on October 31, 1944, by a United Air Lines DC-3 carrying local elected officials and civic leaders.{{cite news |date=November 1, 1944 |title=Bow Lake Field Gets Preview |page=11 |work=Seattle Post-Intelligencer}} The first commercial flights launched in May 1945 with Northwest Airlines, but use was limited due to the U.S. Army Air Force's need for the airport to stage Boeing B-29 bombers for delivery. Various airlines had irregular flights to the airport, which used a Quonset hut with limited heating as a terminal until a permanent building was financed by a bond issue that voters approved in 1946.

The first scheduled commercial flights began on September 1, 1947, with Northwest Airlines and Western Airlines operating ten daily departures.{{cite web |last=Swift |first=Cathy |date=July 7, 2023 |title=SEA Airport: Then and Now |url=https://www.portseattle.org/blog/sea-airport-then-and-now |publisher=Port of Seattle |accessdate=May 24, 2024}} They were joined by United, Alaska, Trans-Canada, Western, and Pan Am by 1951 as airlines departed from Boeing Field.{{cite web |last=Crowley |first=Walt |date=August 17, 2003 |title=Sea-Tac International Airport: Part 2 — From Props to Jets (1950-1970) |url=https://www.historylink.org/File/4232 |work=HistoryLink |accessdate=May 24, 2024 |archive-date=May 25, 2024 |archive-url=https://web.archive.org/web/20240525063537/https://www.historylink.org/File/4232 |url-status=live }} The terminal at the renamed Seattle–Tacoma International Airport was formally dedicated by Governor Arthur Langlie on July 9, 1949, in front of a crowd of 30,000 spectators.{{cite book |last1=Oldham |first1=Kit |last2=Blecha |first2=Peter |author-link2=Peter Blecha |author3=HistoryLink Staff |year=2011 |title=Rising Tides and Tailwinds: The Story of the Port of Seattle 1911–2011 |page=60 |publisher=Port of Seattle, HistoryLink, University of Washington Press |location=Seattle |isbn=9780295991313 |oclc=713189816}} The {{convert|71,000|sqft|sqm|adj=mid}} building, designed by architect Herman A. Moldenhour, included a rooftop control tower and glass courting walls in the concourses.{{cite news |last=Langlow |first=Leonard S. |date=July 10, 1949 |title=Dedicate Huge New Airport; 30,000 At Colorful Ceremony |page=1 |work=The News Tribune |url=https://www.newspapers.com/article/the-news-tribune-dedicate-huge-new-airpo/148086132/ |via=Newspapers.com |accessdate=May 25, 2024 |archive-date=May 26, 2024 |archive-url=https://web.archive.org/web/20240526041325/https://www.newspapers.com/article/the-news-tribune-dedicate-huge-new-airpo/148086132/ |url-status=live }} The {{convert|907|acre|ha|adj=mid}} airport originally had four runways at 45-degree angles, between {{convert|5000|and|6100|ft|m}} long, for crosswind operations. The two perpendicular runways were arranged into an "X"-shape that intersected near the longest, north–south runway; an additional runway to the south ran east–west.{{cite web |date=February 6, 2024 |title=1950–1959: SEA Airport Takes Off |url=https://www.portseattle.org/blog/1950-1959-sea-airport-takes |publisher=Port of Seattle |accessdate=May 25, 2024}} The terminal building's "inverted V" shape was arranged to match the runway layout.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|pp=64–65}} The north–south runway (now Runway 16L/34R){{cite web |last=Donnelly |first=Devlin |date=July 15, 2019 |title=Why Is SEA Airport Shaped Like a Boomerang? |url=https://www.portseattle.org/blog/why-sea-tac-airport-shaped-boomerang |publisher=Port of Seattle |accessdate=May 25, 2024 |archive-date=May 26, 2024 |archive-url=https://web.archive.org/web/20240526032903/https://www.portseattle.org/blog/why-sea-tac-airport-shaped-boomerang |url-status=live }} was lengthened to {{Convert|7500|ft|abbr=on}} in 1950, to {{Convert|8500|ft|abbr=on}} in 1955, and to {{Convert|10200|ft|abbr=on}} in 1958 to support commercial jetliners.{{cite news |last=Loschen |first=Roger |date=July 5, 1959 |title=The First 10 Years Are the 'Growingest' |pages=9–12 |work=The Seattle Times}}

The first parking lot at Sea–Tac opened in 1955 with room for 527 vehicles. The United States Postal Service opened its air mail terminal at the airport in 1957 to serve areas west of the Mississippi River and mail bound for Asia; other government agencies, including the Weather Bureau and the Customs Service also established offices at Sea–Tac. On June 28, 1959, Japan Airlines became the first international carrier to operate at Sea–Tac when it began its service to Tokyo. Several projects were completed by 1961 to prepare for the Seattle World's Fair the following year, including a runway extension over South 188th Street, which was placed in an automobile tunnel that opened in July 1961.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=74}}{{cite news |date=July 6, 1961 |title=Opening Set For Subway At Sea-Tac |page=12 |work=The Seattle Times}} During construction of the runway extension in February 1961, the fossilized skeleton of a Megalonyx jeffersonii giant sloth was discovered and excavated for display at the Burke Museum in Seattle.{{cite news |last1=Nesbitt |first1=Elizabeth A. |last2=Williams |first2=David B. |date=September 15, 2023 |title='Spirit Whales & Sloth Tales' tracks Washington fossils and their stories |url=https://www.seattletimes.com/pacific-nw-magazine/spirit-whales-and-sloth-tales-tracks-washington-fossils-and-their-stories/ |work=The Seattle Times |accessdate=May 25, 2024 |archive-date=May 26, 2024 |archive-url=https://web.archive.org/web/20240526035800/https://www.seattletimes.com/pacific-nw-magazine/spirit-whales-and-sloth-tales-tracks-washington-fossils-and-their-stories/ |url-status=live }} The two-story North Concourse (later named Concourse D){{cite web |date=January 2024 |title=Building Up: 75 Years of Service |url=https://www.portseattle.org/sites/default/files/2024-01/SEA_75BuildingUp_FINAL.pdf |publisher=Port of Seattle |accessdate=May 25, 2024 |archive-date=May 23, 2024 |archive-url=https://web.archive.org/web/20240523130227/https://www.portseattle.org/sites/default/files/2024-01/SEA_75BuildingUp_FINAL.pdf |url-status=live }} opened a month later with four gate positions to prepare for regular jetliner service; the concourse's wing was {{convert|600|ft|m}} long and {{convert|30|ft|m}} wide.{{cite web |title=Port of Seattle Centennial: Main Terminal |url=http://www.portseattle100.org/properties/main-terminal |publisher=Port of Seattle |url-status=dead |archive-url=https://web.archive.org/web/20120505223223/http://www.portseattle100.org/properties/main-terminal |archive-date=May 5, 2012 |accessdate=June 19, 2012}} Jetliner service began in October with Pan Am's Boeing 707 to Honolulu. The {{convert|688|ft|m|adj=mid|-long}} South Concourse (now Concourse A) opened in May 1961 alongside an expanded parking lot with capacity for 2,000 vehicles.{{cite news |date=May 19, 1961 |title=Sea-Tac Opens Extension |page=11 |work=The News Tribune |url=https://www.newspapers.com/article/the-news-tribune-sea-tac-opens-extension/148085994/ |via=Newspapers.com |accessdate=May 25, 2024}}

The {{convert|800|ft|m|adj = on}} long Concourse B opened in December 1964. It added eight gate positions, bringing the total to 19, a {{convert|12000|sqft|m2}} area housing international arrivals and the offices of U.S. Customs, Immigration, Public Health and the Department of Agriculture. Concourse C opened in July 1966. Four years later, it was extended to include another 10 gates, bringing the total to 35. The first non-stop flights from Sea–Tac to mainland Europe began in September 1966 with Scandinavian Airlines, who used a polar route to reach Copenhagen. A parallel second runway was completed {{convert|800|ft|m}} west of the main runway in 1970.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=74}}

The Port embarked on a major expansion plan, designed by The Richardson Associates{{cite web |title=AIA Seattle Honor Awards: projects cited 1950– |url=http://www.aiaseattle.org/archive_honorawards_1950topresent.htm |url-status=dead |archive-url=https://web.archive.org/web/20100620174939/http://aiaseattle.org/archive_honorawards_1950topresent.htm |archive-date=June 20, 2010 |publisher=AIA Seattle, A Chapter of the American Institute of Architects }} and lasting from 1967 to 1973, adding a second runway, a parking garage, two satellite terminals and other improvements. In 1973, $28 million new terminal was built over and around the 1949 structure;{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=74}} the new terminal quadrupled the area for public use.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=77}} On July 1, 1973, the airport opened two new satellite terminals, along with an underground train system to connect them to the Main Terminal.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=77}}{{cite web |title=North and South Satellites |url=http://portseattle100.org/properties/satellite-terminals |url-status=dead |archive-url=https://web.archive.org/web/20121211123305/http://www.portseattle100.org/properties/satellite-terminals |archive-date=December 11, 2012 |publisher=Port of Seattle }} These fully automatic shuttle trains were among the first of their kind in the United States. Also unprecedented in any U.S. airport: as part of the expansion the Port commissioned $300,000 worth of artworks; these were the start of what would become a large public art collection owned by the Port.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=77}}

In the mid-1980s, the Main Terminal was renovated and another {{convert|150|ft|m}} was added to the north end. Concourse D was expanded in 1987 with a rotunda that added four new gates. In 1993, Concourses B, C, and D were renovated. The project, designed by NBBJ, included the addition of {{convert|150000|sqft|m2}} and the renovation of {{convert|170000|sqft|m2}} of space in Concourses B, C, and D.{{Cite journal |last=International Academy of Architecture |year=1995 |title=Renovations Are Needed at Sea–Tac International Airport |journal=World Architecture |location=London |publisher=Grosvenor Press International, Ltd. |issue=35–36}} On June 15, 2004, the {{convert|2102|ft|m|adj = on}} new Concourse A was unveiled with 14 new gates, a dozen new restaurants, new artwork and the airport's first moving sidewalks.

Residents of the surrounding area filed lawsuits against the Port in the early 1970s, complaining of noise, vibration, smoke, and other problems. The Port and the government of King County adopted the Sea–Tac Communities Plan in 1976 to address problems and guide future development. The Port spent more than $100 million over the next decade to buy homes and school buildings in the vicinity, and soundproof others nearby. In the mid-1980s, the airport participated in the airport noise-compatibility program initiated by Congress in 1979. Airport-noise contours were developed, real estate was purchased and some homes were retrofitted to achieve noise mitigation.C. Michael Hogan, Ballard George et al., Residential noise insulation at Seattle Tacoma International Airport, Earth Metrics Inc., published by the Federal Aviation Administration and Seattle Tacoma International Airport (1984).

In 1978 the U.S. ended airline regulation, and the U.S. airlines were allowed to determine routes and fares without government approval. Deregulation resulted in some new service to Seattle, including from TWA, then the fourth-largest U.S. airline, as well as Delta, National, and American.

Image:SeaTacTerminalN.jpg and United planes at the North Satellite Terminal in 2008]]

Image:View from SEA Tower.jpg

Shortly after the death of U.S. Senator Henry Martin "Scoop" Jackson, the Port Commission voted on September 13, 1983, to change the airport's name to the Henry M. Jackson International Airport. Citizens of Tacoma were angered by the removal of their city's name despite their contribution to the airport's original construction budget, which had come with a promise to share the name. An additional complicating factor was the existence of another Jackson International Airport (now Jackson–Medgar Wiley Evers International Airport) in Jackson, Mississippi.{{cite news |last=Banel |first=Feliks |date=May 26, 2023 |title=When Sea-Tac Airport disappeared for six months |url=https://mynorthwest.com/3139553/all-over-the-map-sea-tac-airport-monument-to-end-of-inter-city-war/ |publisher=KIRO-FM |accessdate=May 24, 2024 |archive-date=May 25, 2024 |archive-url=https://web.archive.org/web/20240525065657/https://mynorthwest.com/3139553/all-over-the-map-sea-tac-airport-monument-to-end-of-inter-city-war/ |url-status=live }} During the November 1983 elections, an advisory referendum in Tacoma on the airport's name endorsed the original name by a 4–1 margin and two incumbent Port commissioners were defeated by candidates in favor of restoring the Sea–Tac name.{{cite news |last=McDonough |first=Sandra |date=February 29, 1984 |title=Renaming of airport hailed as triumph for public |page=C1 |work=The Seattle Times}} Helen Jackson, the widow of the late senator, expressed her desire that their family remain neutral in the debate.{{cite news |date=February 20, 1984 |title=Airport conflict saddens Jackson's widow |page=B1 |work=The News Tribune |agency=Associated Press |url=https://www.newspapers.com/article/the-news-tribune-airport-conflict-sadden/148030468/ |via=Newspapers.com |accessdate=May 24, 2024 |archive-date=May 25, 2024 |archive-url=https://web.archive.org/web/20240525065656/https://www.newspapers.com/article/the-news-tribune-airport-conflict-sadden/148030468/ |url-status=live }} With a 3–2 vote of the Port Commission on February 28, 1984, the name reverted to Seattle–Tacoma International Airport and the four signs with Jackson's name were removed.{{cite news |last=Gillie |first=John |date=February 29, 1984 |title=It's Sea-Tac again, amid rejoicing |page=A1 |work=The News Tribune |url=https://www.newspapers.com/article/the-news-tribune-its-sea-tac-again-ami/148030509/ |via=Newspapers.com |accessdate=May 24, 2024}}

In the late 1980s, the Port of Seattle and a council representing local county governments considered the future of air traffic in the region and predicted that the airport could reach capacity by 2000. The rising use of regional airliners such as Horizon Air caused aircraft movements to triple from 1978 to 1990 and air cargo use at the airport had also risen dramatically.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|pp=87, 90}} In 1992, the planning committee concluded that the best solution was to add a third runway to the airport and construct a supplemental two-runway airport in one of the neighboring counties. Members of the community opposed a third runway, as did the Highline School District and the cities of Des Moines, Burien, Federal Way, Tukwila, and Normandy Park,{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=91}} but a 1994 study concluded there were no feasible sites for an additional airport. The Port of Seattle approved a plan for the new runway in 1996, prompting a lawsuit from opponents. The Port secured the necessary permits by agreeing to noise reduction programs and environmental protections.{{cite news |last1=Lange |first1=Larry |title=State allowed to join lawsuit on 3rd runway at Sea-Tac |url=https://www.seattlepi.com/news/article/state-allowed-to-join-lawsuit-on-3rd-runway-at-1120066.php |access-date=December 18, 2023 |work=Seattle Post-Intelligencer |date=July 23, 2003 |archive-date=December 19, 2023 |archive-url=https://web.archive.org/web/20231219000025/https://www.seattlepi.com/news/article/state-allowed-to-join-lawsuit-on-3rd-runway-at-1120066.php |url-status=live }} Runway opponents appealed these permits, but dropped their challenges in 2004.{{cite web |last=Wilma |first=David |date=September 16, 2004 |title=Airport Communities Coalition drops opposition to Sea-Tac International Airport third runway on August 19, 2004. |url=https://www.historylink.org/File/5733 |work=HistoryLink |access-date=December 18, 2023 |archive-date=December 19, 2023 |archive-url=https://web.archive.org/web/20231219000026/https://www.historylink.org/File/5733 |url-status=live }}

The third runway, measuring {{convert|8,500|ft|m}} long, opened on November 20, 2008, with a construction cost of $1.1 billion. Parallel to the existing two, the new runway is {{Convert|2500|ft|abbr=on}} west of runway 34R, allowing landings on both in times of low visibility. The older runways are {{Convert|800|ft|abbr=on}} apart, too close to allow use of both in low visibility.{{cite web |title=Sea–Tac's third runway set to open after years of delay |url=http://seattletimes.com/html/localnews/2008204574_thirdrunway26m.html |url-status=live |archive-url=https://web.archive.org/web/20131004215619/http://seattletimes.com/html/localnews/2008204574_thirdrunway26m.html |archive-date=October 4, 2013 |access-date=October 1, 2013 |website=The Seattle Times}} The third runway project included {{convert|13|e6cuyd|m3}} of fill dirt and several retaining walls, the longest of which is {{convert|1,430|ft|m}} long and {{convert|130|ft|m}} tall.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=103}}

The airport's Central Terminal building was renovated and expanded in 2003 in a project designed by Curtis W. Fentress, of Fentress Architects.{{cn|date=June 2024}} The renovation and expansion began in 1996 and underwent extensive modifications to accommodate new security requirements following the September 11 attacks in 2001.{{sfnp|Oldham|Blecha|HistoryLink Staff|2011|p=100}}

In 2014, Delta Air Lines announced plans to expand Seattle into a transpacific hub. Since then, Delta has added numerous international flights and dozens of domestic flights to feed those services. Delta's increased presence in Seattle has been seen by some industry analysts as a response to United Airlines' transpacific hub at San Francisco, as well as Delta's disenchantment with its former Tokyo–Narita hub.{{Cite news |last=Carey |first=Susan |date=June 29, 2014 |title=Delta, Alaska Airlines Go to War Over Seattle |work=The Wall Street Journal |url=https://online.wsj.com/articles/delta-alaska-airlines-go-to-war-over-seattle-1404076082 |url-status=live |access-date=November 19, 2014 |archive-url=https://web.archive.org/web/20141022094244/http://online.wsj.com/articles/delta-alaska-airlines-go-to-war-over-seattle-1404076082 |archive-date=October 22, 2014}}

In late 2021, shortly after Alaska Airlines joined American Airlines in the Oneworld alliance, American announced that they would increase their international presence in Seattle.{{Cite news |date=September 30, 2021 |title=American Airlines to turn Seattle into Asian hub |language=en |work=ch-aviation |url=https://www.ch-aviation.com/portal/news/108145-american-airlines-to-turn-seattle-into-asian-hub |access-date=October 1, 2021 |archive-date=October 1, 2021 |archive-url=https://web.archive.org/web/20211001071030/https://www.ch-aviation.com/portal/news/108145-american-airlines-to-turn-seattle-into-asian-hub |url-status=live }} However, as of 2023, American had abandoned plans for long-haul flights to Asia from Seattle (including its proposed service to Bangalore, India) and ended service to London-Heathrow, their only intercontinental service from Seattle.{{Cite web |last=Schlappig |first=Ben |date=November 19, 2023 |title=American Airlines Abandons Seattle Long Haul Flights |url=https://onemileatatime.com/news/american-airlines-abandons-seattle-flights/ |access-date=November 19, 2023 |website=One Mile at a Time |language=en-US |archive-date=August 27, 2023 |archive-url=https://web.archive.org/web/20230827050835/https://onemileatatime.com/news/american-airlines-abandons-seattle-flights/ |url-status=live }}

The North Satellite Terminal only received limited upgrades since it opened in 1973, and needed modernization.{{Cite news |last=Farley |first=Glenn |date=September 13, 2016 |title=Sea–Tac moves forward with major construction project |work=KING-TV |url=http://www.king5.com/tech/science/aerospace/photos-sea-tac-gate-expansion/318032748 |url-status=live |access-date=June 28, 2017 |archive-url=https://web.archive.org/web/20170828185859/http://www.king5.com/tech/science/aerospace/photos-sea-tac-gate-expansion/318032748 |archive-date=August 28, 2017}} The Port of Seattle initially looked at simply updating the terminal in a project it called the North Satellite Renovation Plan (NorthSTAR). In 2016, the Port announced it would also significantly expand the terminal. The $550 million project called the North Satellite Modernization increased the size of the North Satellite by {{Convert|201000|sqft}} and another eight gates, bringing the total to 20. The project's first phase, dedicated on July 11, 2019, expanded the terminal to the west by {{convert|240|ft|m}} and added eight gates, a mezzanine level with eateries, and a rooftop lounge for Alaska Airlines. The second phase modernized the remaining areas of the old terminal and expands dining and retail space around the twenty existing gates. The new terminal opened on June 29, 2021.{{Cite news |last=Vedantam |first=Keerthi |date=July 11, 2019 |title=New gates, posh lounge at Sea-Tac airport give Alaska Airlines an upgrade |work=The Seattle Times |url=https://www.seattletimes.com/business/boeing-aerospace/new-gates-posh-lounge-at-sea-tac-give-alaska-airlines-an-upgrade/ |url-status=live |access-date=July 12, 2019 |archive-url=https://web.archive.org/web/20190712071829/https://www.seattletimes.com/business/boeing-aerospace/new-gates-posh-lounge-at-sea-tac-give-alaska-airlines-an-upgrade/ |archive-date=July 12, 2019}}

File:IAF Pedestrian Walkway.jpgIn 2022, the Port of Seattle completed a new {{Convert|450000|sqft|adj=on}} International Arrivals Facility (IAF) east of Concourse A, along with a {{Convert|900|ft|adj=on}}-long high bridge that will take passengers from the South Satellite, up {{Convert|85|ft}} above the existing taxiway and over the top of Concourse A.{{cite web | url=https://www.portseattle.org/news/port-welcomes-first-flight-new-international-arrivals-facility-sea-airport | title=Port Welcomes First Flight into New International Arrivals Facility at SEA Airport | access-date=March 1, 2023 | archive-date=March 1, 2023 | archive-url=https://web.archive.org/web/20230301214037/https://www.portseattle.org/news/port-welcomes-first-flight-new-international-arrivals-facility-sea-airport | url-status=live }} The project was initially expected to be completed by 2021 at a cost of $766 million,{{Cite news |last=Gates |first=Dominic |date=August 14, 2017 |title=Cost of Sea–Tac's two big expansion projects rises 17 percent |work=The Seattle Times |url=http://www.seattletimes.com/business/boeing-aerospace/cost-of-sea-tacs-two-big-expansion-projects-rises-17-percent/ |url-status=live |access-date=August 28, 2017 |archive-url=https://web.archive.org/web/20170828192052/http://www.seattletimes.com/business/boeing-aerospace/cost-of-sea-tacs-two-big-expansion-projects-rises-17-percent/ |archive-date=August 28, 2017}}{{cite web |title=Airport Projects – Int'l Arrivals Facility |url=https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Pages/iaf_revised.aspx |url-status=dead |archive-url=https://web.archive.org/web/20170828190814/https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Pages/iaf_revised.aspx |archive-date=August 28, 2017 |access-date=August 28, 2017 |website=www.portseattle.org |publisher=Port of Seattle |language=en-us}} though revised to $968 million in late 2018.{{cite web |last=Gates |first=Dominic |date=September 11, 2018 |title=Price tag for Sea-Tac's new International Arrivals Facility soars to almost $1 billion |url=https://www.seattletimes.com/business/boeing-aerospace/price-tag-for-sea-tacs-new-international-arrivals-facility-soars-to-almost-1-billion/ |access-date=November 23, 2019 |website=The Seattle Times |archive-date=November 23, 2019 |archive-url=https://web.archive.org/web/20191123004502/https://www.seattletimes.com/business/boeing-aerospace/price-tag-for-sea-tacs-new-international-arrivals-facility-soars-to-almost-1-billion/ |url-status=live }} The old customs and immigration facility was located in the basement of the South Satellite, and operated well over its design capacity. Additionally, the process for passengers was complicated by the satellite's isolated location.{{Cite news |last=Gates |first=Dominic |date=September 29, 2016 |title=Designs show future of Sea–Tac's international arrivals hub |work=The Seattle Times |url=http://www.seattletimes.com/business/boeing-aerospace/designs-show-future-of-sea-tacs-international-arrivals-hub/ |url-status=live |access-date=August 28, 2017 |archive-url=https://web.archive.org/web/20170828192915/http://www.seattletimes.com/business/boeing-aerospace/designs-show-future-of-sea-tacs-international-arrivals-hub/ |archive-date=August 28, 2017}} With the opening of the new IAF, Concourse A will now also be used for arriving international flights, nearly doubling the number of gates capable of serving arriving international passengers. The South Satellite Terminal is also planned to be renovated. The IAF was initially designed to accommodate 20 widebody aircraft, but four gates were not built to those specifications; the discrepancy was described as a "design flaw" by the Port of Seattle and blamed on the project's contractor.{{cite news |last=Gates |first=Dominic |date=April 7, 2023 |title=Sea-Tac Airport's new $1B international terminal too tight a squeeze for 20 big jets |url=https://www.seattletimes.com/business/boeing-aerospace/sea-tac-airports-new-1b-international-terminal-too-tight-a-squeeze-for-20-big-jets/ |work=The Seattle Times |accessdate=April 11, 2023 |archive-date=April 12, 2023 |archive-url=https://web.archive.org/web/20230412050319/https://www.seattletimes.com/business/boeing-aerospace/sea-tac-airports-new-1b-international-terminal-too-tight-a-squeeze-for-20-big-jets/ |url-status=live }}

The airport's digital infrastructure, including its website, phone lines, check-in system, and automated baggage sorting, was disabled by a cyberattack on August 24, 2024.{{cite news |last=Freeman |first=Caitlyn |date=August 26, 2024 |title=Little known about cyberattack that has disrupted Sea-Tac Airport |url=https://www.seattletimes.com/seattle-news/little-known-about-cyberattack-that-has-disrupted-sea-tac-airport/ |work=The Seattle Times |accessdate=September 11, 2024}} Most of the systems were restored by August 31, but the Port of Seattle websites and passenger information systems remained offline.{{cite news |last1=Rose |first1=Andy |last2=Jaime |first2=Caroline |date=August 31, 2024 |title=Seattle airport says high volume carriers resume normal operations following cyberattack ahead of holiday weekend |url=https://www.cnn.com/2024/08/29/travel/seattle-airport-cyberattack/index.html |publisher=CNN |accessdate=September 11, 2024}}

The airport has seen record growth in passenger traffic in the 2010s and 2020s. The busiest day for outbound passengers was July 24, 2023, with 73,651 passengers; more than 198,000 passengers (departing, arriving, and connecting) passed through the airport that day. The previous record for outbound passengers was set on August 16, 2019, at 72,154.{{cite press release |date=September 28, 2023 |title=Record-Breaking Summer: 15.3 Million Passengers Set New Milestones |url=https://www.portseattle.org/news/record-breaking-summer-153-mil-passengers |publisher=Port of Seattle |access-date=October 19, 2023 |archive-date=October 14, 2023 |archive-url=https://web.archive.org/web/20231014020027/https://www.portseattle.org/news/record-breaking-summer-153-mil-passengers |url-status=live }} The growth has been partly fueled by the nationwide expansion of Seattle-based Alaska Airlines and by Delta Air Lines setting up a major international hub at SEA Airport. That growth has strained the airport's facilities and led the port to invest more than $2 billion into several expansion and renovation projects.{{Cite news |last=Gates |first=Dominic |date=January 26, 2017 |title=Sea–Tac airport's booming passenger volume makes it ninth busiest in U.S. |work=The Seattle Times |url=http://www.seattletimes.com/business/boeing-aerospace/sea-tac-airports-booming-passenger-volume-makes-it-9th-busiest-in-us/ |url-status=live |access-date=June 28, 2017 |archive-url=https://web.archive.org/web/20170828193018/http://www.seattletimes.com/business/boeing-aerospace/sea-tac-airports-booming-passenger-volume-makes-it-9th-busiest-in-us/ |archive-date=August 28, 2017}}

The airport has six outbound baggage handling systems with limited to no cross-connectivity. The system now in place is aging and reaching its maximum capacity. A $320.4 million project will create one unified, high-speed baggage system under the airport.{{cite web |date=February 2017 |title=Sea–Tac Infrastructure Folio |url=https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Documents/Sea-Tac_infrastructure_Folio.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170828191340/https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Documents/Sea-Tac_infrastructure_Folio.pdf |archive-date=August 28, 2017 |access-date=June 28, 2017 |publisher=Port of Seattle}} That will allow bags to be checked from any ticketing counter, to receive security screening faster, and to be routed to any gate in the airport. The extra efficiency and speed will allow the airport to handle more baggage in the future without expanding the footprint of the baggage handling systems. The initial phase of the project was finished in 2018 and the entire system is scheduled to be completed in 2027.{{Cite news |last=Gates |first=Dominic |date=September 13, 2016 |title=Expanded terminal for Alaska Airlines OK'd at Sea–Tac |work=The Seattle Times |url=http://www.seattletimes.com/business/boeing-aerospace/expanded-terminal-for-alaska-airlines-okd-at-sea-tac/ |url-status=live |access-date=June 28, 2017 |archive-url=https://web.archive.org/web/20170828192715/http://www.seattletimes.com/business/boeing-aerospace/expanded-terminal-for-alaska-airlines-okd-at-sea-tac/ |archive-date=August 28, 2017}}{{cite web |title=Baggage Handling System Optimization |url=https://www.portseattle.org/projects/baggage-handling-system-optimization |publisher=Port of Seattle |url-status=dead |archive-url=https://web.archive.org/web/20240526152031/https://www.portseattle.org/projects/baggage-handling-system-optimization |archive-date=May 26, 2024 |accessdate=September 11, 2024}}

With estimates that the Puget Sound region will grow by another one million people by 2035, the Port of Seattle began developing the Sustainable Airport Master Plan (SAMP) in 2018 to meet passenger and cargo demands. The SAMP recommends more than 30 projects to improve efficiency and airport access, including a new terminal with 19 gates and an automated people mover through three separate stations.{{cite web |title=Sustainable Airport Master Plan (SAMP) |url=https://www.portseattle.org/plans/sustainable-airport-master-plan-samp |access-date=November 23, 2019 |website=Port of Seattle}} Near-term projects that are scheduled to be completed in the 2020s include restroom renovations, security checkpoint expansion, and roadway realignment.{{cite news |last=Roberts |first=Paul |date=May 15, 2024 |title=Sea-Tac Airport's facelift means upgrades … and work zones |url=https://www.seattletimes.com/business/sea-tac-airports-facelift-means-upgrades-and-work-zones/ |work=The Seattle Times |accessdate=September 11, 2024 |archive-date=September 12, 2024 |archive-url=https://web.archive.org/web/20240912062224/https://www.seattletimes.com/business/sea-tac-airports-facelift-means-upgrades-and-work-zones/ |url-status=live }} A four-story addition to the existing structure of Concourse C began in 2023 and is scheduled to be completed in 2027 at a cost of $399 million; it includes a "central gathering place" under a large wooden ceiling.{{cite news |last=Hinchcliffe |first=Emma |date=October 2, 2023 |title=Port of Seattle approves $400M expansion at Sea-Tac Airport |url=https://www.djc.com/news/ae/12159556.html |work=Seattle Daily Journal of Commerce |accessdate=September 29, 2024 |archive-date=December 2, 2024 |archive-url=https://web.archive.org/web/20241202070942/https://www.djc.com/news/ae/12159556.html |url-status=live }} Further projects include an automated parking garage guidance system, a gateway project in cooperation with Alaska Airlines, Concourse A building expansion for lounges, improved curbside safety and accessibility, continued refurbishment of the Central Terminal, and a replacement of controls pertaining to the SEA Underground shuttles.{{cn|date=September 2024}}

File:SeaTacTerminalMain.jpg

File:SeaTacMtRainier.jpg in the distance]]

The airport has 115 gates{{cite press release |date=July 9, 2024 |title=SEA Celebrates 75 Years of Service Ahead of Expected Record Year |url=https://www.portseattle.org/news/sea-celebrates-75-years-service-ahead-expected-record-year |publisher=Port of Seattle |accessdate=July 10, 2024 |archive-date=July 10, 2024 |archive-url=https://web.archive.org/web/20240710010126/https://www.portseattle.org/news/sea-celebrates-75-years-service-ahead-expected-record-year |url-status=live }} in four concourses and two satellite buildings.{{cite web |title=Maps – Port of Seattle |url=https://www.portseattle.org/sea-tac/maps |access-date=April 2, 2021 |archive-date=January 11, 2022 |archive-url=https://web.archive.org/web/20220111072142/https://www.portseattle.org/sea-tac/maps |url-status=live }} The two satellite terminal buildings, named the North and South Satellites, are connected to the four concourses in the main terminal by a three-line automated people mover system called the SEA Underground. The underground transit system moves passengers within the four concourses of the central terminal and out to the two satellite terminals.{{cite web |last=Ciceron |first=Dianne |date=March 17, 2022 |title=All Aboard the SEA Underground |url=https://www.portseattle.org/blog/all-aboard-sea-underground |publisher=Port of Seattle |accessdate=July 1, 2024 |archive-date=May 18, 2024 |archive-url=https://web.archive.org/web/20240518004429/https://www.portseattle.org/blog/all-aboard-sea-underground |url-status=live }}

All non-precleared international arrivals arrive at the South Satellite or Concourse A, regardless of their departure terminal.{{cite web |title=International Arrivals and Passport Control – Port of Seattle |url=https://www.portseattle.org/services-amenities/international-arrivals-and-passport-control |access-date=March 1, 2023 |publisher=Port of Seattle |archive-date=January 11, 2022 |archive-url=https://web.archive.org/web/20220111073645/https://www.portseattle.org/services-amenities/international-arrivals-and-passport-control |url-status=live }} A dedicated international arrivals facility with customs control is on the southeast side of the terminal building and connected to the South Satellite via an overhead walkway and to the Concourse A gates via sterile walkways. The overhead bridge from the South Satellite is {{convert|780|ft|m}} long and rises {{convert|87|ft|m}} over a taxiway.

• Concourse A contains 16 gates, and is primarily used by Delta Air Lines, United Airlines, and several international carriers.{{cite web |last=Johnson |first=Rosa |date=October 30, 2020 |title=User's Guide to the Train at SEA Airport |url=https://www.portseattle.org/blog/users-guide-train-sea-airport |publisher=Port of Seattle |accessdate=June 24, 2024}}
• Concourse B contains 17 gates, and is primarily used by Delta Air Lines and Southwest Airlines.
• Concourse C contains 27 gates, and is used exclusively by Alaska Airlines.
• Concourse D contains 17 gates, and is mainly used by Alaska Airlines and American Airlines.
• North Satellite contains 20 gates, and is used exclusively by Alaska Airlines.
• South Satellite contains 14 gates, and is used by Delta Air Lines, Hawaiian Airlines, and many domestic and international carriers.

The five security checkpoints at Sea–Tac are located in the main terminal and are managed by the Transportation Security Administration (TSA). All of the checkpoints offer Clear Secure prescreening, while TSA Precheck is available from two.{{cite news |last=Bikales |first=James |date=September 19, 2022 |title=TSA line stretching into Seattle parking garage caused hour-plus waits |url=https://www.washingtonpost.com/travel/2022/09/19/seattle-security-lines/ |newspaper=The Washington Post |accessdate=March 1, 2024 |archive-date=March 24, 2023 |archive-url=https://web.archive.org/web/20230324005418/https://www.washingtonpost.com/travel/2022/09/19/seattle-security-lines/ |url-status=live }} The airport began using a virtual queuing program, called SEA Spot Saver, in 2021 to reduce wait times and control crowds at security lines.{{cite news |last=Schlosser |first=Kurt |date=May 4, 2021 |title=Seattle airport testing new tech to allow travelers to wait in virtual line for security screening |url=https://www.geekwire.com/2021/seattle-airport-testing-new-tech-allow-travelers-wait-virtual-line-security-screening/ |work=GeekWire |accessdate=March 1, 2024 |archive-date=October 9, 2024 |archive-url=https://web.archive.org/web/20241009061419/https://www.geekwire.com/2021/seattle-airport-testing-new-tech-allow-travelers-wait-virtual-line-security-screening/ |url-status=live }} Wait times at the TSA checkpoints during peak departure periods averaged 20 minutes in 2019 and increased during the COVID-19 pandemic, with a maximum of 90 minutes reached in June 2023.{{cite news |last=Saldanha |first=Alison |date=July 29, 2023 |title=Sea-Tac Airport just set a passenger record. Wait times are soaring, too |url=https://www.seattletimes.com/business/sea-tac-airport-just-set-a-passenger-record-wait-times-are-soaring-too/ |work=The Seattle Times |accessdate=March 1, 2024 |archive-date=March 2, 2024 |archive-url=https://web.archive.org/web/20240302073222/https://www.seattletimes.com/business/sea-tac-airport-just-set-a-passenger-record-wait-times-are-soaring-too/ |url-status=live }} During particularly busy periods, the queues for security have backed up into the airport's main parking garage and caused several hours of delays for passengers.

The Port of Seattle maintains and curates a collection of public artwork at Sea–Tac that began with acquisitions in 1968 and was formalized with a percent for art ordinance passed in 2000.{{cite news |last=Wilson |first=Gemma |date=November 12, 2024 |title=Sea-Tac's art collection is a visual treat for holiday travelers |url=https://www.seattletimes.com/entertainment/visual-arts/sea-tacs-art-collection-is-a-visual-treat-for-holiday-travelers/ |work=The Seattle Times |accessdate=December 4, 2024 |archive-date=December 7, 2024 |archive-url=https://web.archive.org/web/20241207082423/https://www.seattletimes.com/entertainment/visual-arts/sea-tacs-art-collection-is-a-visual-treat-for-holiday-travelers/ |url-status=live }} The airport's art collection comprises 289 works, which includes paintings, murals, stained glass pieces, video art, and sculptures, and is valued at $40 million.{{cite news |last=Manitach |first=Amanda |date=November 23, 2024 |title=A Look at the Art History of SEA |pages=8–11 |url=https://publicdisplay.art/article/SEA |work=Public Display Art |accessdate=December 4, 2024 |archive-date=December 7, 2024 |archive-url=https://web.archive.org/web/20241207160308/https://publicdisplay.art/article/SEA |url-status=live }} A live music program began as a one-year pilot in 2013 with 20 musicians who performed for 780 total hours.{{cite press release |date=March 27, 2014 |title=Live Music Program Hits High Note With Expanded Offerings at Sea-Tac Airport |url=https://www.flysea.org/news/live-music-program-hits-high-note-expanded-offerings-sea-tac-airport |publisher=Port of Seattle |accessdate=December 4, 2024 |archive-date=December 26, 2024 |archive-url=https://web.archive.org/web/20241226055347/https://www.flysea.org/news/live-music-program-hits-high-note-expanded-offerings-sea-tac-airport |url-status=live }} It was expanded into a permanent airport fixture the following year during daytime hours and was temporarily replaced by a video wall during the COVID-19 pandemic in 2021.{{cite news |last=Brodeur |first=Nicole |date=February 11, 2021 |title=Sea-Tac Airport's new 'music wall' soothes travelers while supporting Seattle-area artists |url=https://www.seattletimes.com/seattle-news/sea-tac-airports-new-music-wall-soothes-travelers-while-supporting-seattle-area-artists/ |work=The Seattle Times |accessdate=December 4, 2024 |archive-date=January 14, 2025 |archive-url=https://web.archive.org/web/20250114010154/https://www.seattletimes.com/seattle-news/sea-tac-airports-new-music-wall-soothes-travelers-while-supporting-seattle-area-artists/ |url-status=live }}

File:KSEA Tower Interior.jpg.]]

The three parallel runways run nearly north–south, west of the passenger terminal, and are {{convert|8500|to(-)|11900|ft|m}} long. In calendar year 2023, the airport had 422,508 aircraft operations, or 1,158 per day: 99% commercial, <1% air taxi, <1% general aviation, and <1% military.{{cite web|url=https://www.portseattle.org/page/airport-statistics|title=Reports-Passenger,Cargo,and Operations Summary-December 2023|website=portseattle.org|accessdate=February 21, 2024|archive-date=November 28, 2019|archive-url=https://web.archive.org/web/20191128222204/https://www.portseattle.org/page/airport-statistics|url-status=live}}

A new control tower was built beginning in 2001 and opened in November 2004, at the cost of $26 million.{{cite web |title=Seattle–Tacoma International Airport (SEA/KSEA), United States of America |url=http://www.airport-technology.com/projects/seatac_tower/ |url-status=live |archive-url=https://web.archive.org/web/20120526190741/http://www.airport-technology.com/projects/seatac_tower/ |archive-date=May 26, 2012 |access-date=August 2, 2009 |website=Airport Technology}} The floor of the new tower's control cab is {{convert|233|ft|m|abbr=on}} above ground level; the tower's overall height including antennas is {{convert|269|ft|m|abbr=on}}. The cab has {{convert|850|sqft|m2|abbr=on}} of space and was designed to support operation by ten controllers, with possible future expansion up to 15. The site and construction method of the tower were designed to maximize the visibility and efficacy of radar systems. The airport's original control tower, built in the 1950s, is now part of the passenger terminal and used as a ramp control tower after being repaired from damage caused by the 2001 Nisqually earthquake.

A recurring problem at the airport is the misidentification of the westernmost taxiway, Taxiway Tango, as a runway. A large "X" has been placed on the north end of the taxiway, but many aircraft have landed on the taxiway.{{Cite news |last=Bowermaster |first=David |date=November 13, 2005 |title=Pilots Mistake Taxiway for Runway at Sea–Tac |work=The Seattle Times |url=https://www.seattletimes.com/business/pilots-mistake-taxiway-for-runway-at-sea-tac/ |url-status=live |access-date=September 17, 2008 |archive-url=https://web.archive.org/web/20071124044044/http://archives.seattletimes.nwsource.com/cgi-bin/texis.cgi/web/vortex/display?slug=seatac13&date=20051113 |archive-date=November 24, 2007}} The FAA issued an alert notice dated from August 27, 2009, to September 24, 2009, urging airplanes about taking precautions such as REILs and other visual cues while landing from the north.

In 2007, the airport became the first to implement an avian radar system providing 24-hour monitoring of wildlife activity across the airfield. This pilot program, designed and implemented with the assistance of the University of Illinois Center of Excellence for Airport Technology (CEAT), was intended to decrease potentially fatal incidents involving collisions with birds and to provide a test bed for the implementation of the technology in the US, which was expected to begin in 2009. The technology is part of a strategy to reduce the presence of wildlife on the airfield.{{cite web |title=Wildlife Management |url=https://www.portseattle.org/Environmental/Water-Wetlands-Wildlife/Pages/Wildlife-Management.aspx |url-status=dead |archive-url=https://web.archive.org/web/20120514184311/http://www.portseattle.org/Environmental/Water-Wetlands-Wildlife/Pages/Wildlife-Management.aspx |archive-date=May 14, 2012 |access-date=July 3, 2012 |website=Port of Seattle}}

The Seattle office of the National Weather Service operates a weather station at the airport, with a temperature gauge between the center and eastern runways. The airport has served as Seattle's official weather recording location since 1945.{{Cite news |last=Quinton |first=Sean |date=August 9, 2018 |title=Temperature readings are higher at Sea-Tac than Seattle this summer. What's the deal? |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/weather/temperature-readings-are-higher-at-sea-tac-than-seattle-this-summer-whats-the-deal/ |url-status=live |access-date=August 9, 2018 |archive-url=https://web.archive.org/web/20180810022808/https://www.seattletimes.com/seattle-news/weather/temperature-readings-are-higher-at-sea-tac-than-seattle-this-summer-whats-the-deal/ |archive-date=August 10, 2018}}

{{As of|April 2023}}, Sea-Tac has over 23,000 total workers, including 400 to 500 customs agents and 850 TSA security officers. The airport has 3,800 cameras that are monitored from a control center staffed by Port of Seattle Airport Operations personnel. A separate control center monitors the baggage handling system at Sea-Tac, which includes {{convert|10|mi|km}} of conveyor belts and handled 14.5 million pieces in 2022.{{cite news |last=Lacitis |first=Erik |date=May 19, 2023 |title=Meet a few of the 23,329 people who keep Sea-Tac Airport humming 24/7 |url=https://www.seattletimes.com/pacific-nw-magazine/meet-a-few-of-the-23329-people-who-keep-sea-tac-airport-humming-24-7/ |work=The Seattle Times |accessdate=July 3, 2024 |archive-date=May 20, 2023 |archive-url=https://web.archive.org/web/20230520020646/https://www.seattletimes.com/pacific-nw-magazine/meet-a-few-of-the-23329-people-who-keep-sea-tac-airport-humming-24-7/ |url-status=live }} Sea-Tac is the first major airport in the U.S. to use filters to remove per- and polyfluoroalkyl substances from its firefighting foam, which had sickened firefighters and workers.{{cite news |last1=Breda |first1=Isabella |last2=Villa |first2=Manuel |date=July 2, 2024 |title=Inside Sea-Tac's efforts to clean up PFAS firefighting foams |url=https://www.seattletimes.com/seattle-news/inside-sea-tacs-efforts-to-clean-up-pfas-firefighting-foams/ |work=The Seattle Times |accessdate=July 3, 2024 |archive-date=July 2, 2024 |archive-url=https://web.archive.org/web/20240702155431/https://www.seattletimes.com/seattle-news/inside-sea-tacs-efforts-to-clean-up-pfas-firefighting-foams/ |url-status=live }}

File:Airport-bound Link train at Westlake Station (2010).jpg train in the Downtown Seattle Transit Tunnel]]

The airport site was chosen partly due to its location along State Route 99, approximately midway between Seattle and Tacoma. Interstate 5 and Interstate 405 also converge near the airport, with an easy connection to the airport via State Route 518 and the Airport Expressway. State Route 509 runs west of the airport, connecting the area to West Seattle. The airport is the largest generator of vehicle trips in the state.{{cite web |title=SR 509: Corridor Completion/I-5/South Access Road Final Environmental Impact Statement |url=http://www.wsdot.wa.gov/NR/rdonlyres/1AC95DE6-F6CB-4D7B-B1D9-7A99B7D33FE2/0/chapter_1.pdf |url-status=dead |archive-url=https://web.archive.org/web/20130624013820/http://www.wsdot.wa.gov/NR/rdonlyres/1AC95DE6-F6CB-4D7B-B1D9-7A99B7D33FE2/0/chapter_1.pdf |archive-date=June 24, 2013 |access-date=May 4, 2013 |publisher=Washington State Department of Transportation}}

The Port of Seattle offers paid on-site parking in a 12,100-space garage, notable for being North America's largest parking structure under one roof.{{cite web |title=Airport Parking Garage |url=http://www.portseattle100.org/properties/parking-garage |url-status=dead |archive-url=https://web.archive.org/web/20140729051558/http://www.portseattle100.org/properties/parking-garage |archive-date=July 29, 2014 |access-date=January 1, 2016 |publisher=Port of Seattle}} The airport also offers valet parking and electric vehicle charging stations. Several privately owned parking facilities are located off-site near the airport with shuttle access.{{cite news |last=Elliott |first=Christopher |date=October 5, 2020 |title=Here's how airport parking has changed due to the COVID-19 pandemic |url=https://www.seattletimes.com/life/travel/heres-how-airport-parking-has-changed-due-to-the-covid-19-pandemic-travel-troubleshooter/ |work=The Seattle Times |access-date=February 16, 2023 |archive-date=February 17, 2023 |archive-url=https://web.archive.org/web/20230217064233/https://www.seattletimes.com/life/travel/heres-how-airport-parking-has-changed-due-to-the-covid-19-pandemic-travel-troubleshooter/ |url-status=live }}

The airport is served by the 1 Line of Sound Transit's Link light rail system at the SeaTac/Airport station with frequent service to downtown Seattle and the University of Washington. The station opened on December 19, 2009, and is connected to the airport terminal via a pedestrian bridge to the airport parking garage.{{Cite news |date=December 19, 2009 |title=Light Rail Service Begins to Sea–Tac Airport |work=The Seattle Times |agency=Associated Press |url=http://seattletimes.nwsource.com/html/localnews/2010548590_apwalightrailairport.html |url-status=live |access-date=July 3, 2012 |archive-url=https://web.archive.org/web/20110622014712/http://seattletimes.nwsource.com/html/localnews/2010548590_apwalightrailairport.html |archive-date=June 22, 2011}} Another pedestrian bridge over International Boulevard is used to access the city of SeaTac, nearby airport hotels, and King County Metro buses including RapidRide A Line. A 1.6-mile light rail extension south to Angle Lake station at South 200th Street opened on September 24, 2016.

The airport is also served both by the King County Metro bus system and Sound Transit regional express buses. Sound Transit buses offer service to West Seattle, White Center, Burien, Renton, Newcastle and Bellevue through Route 560. In contrast, Route 574 offers service to Lakewood via Des Moines, Federal Way, and Tacoma.

Tukwila Station, which is approximately 5 miles east of the airport, is served by Sounder commuter rail and Amtrak Cascades regional inter-city rail with service north to Vancouver, Canada, and service south to Portland and Eugene in Oregon. This station can be reached in about 30 minutes via the Central Link light rail or the RapidRide A Line bus service and transferring at Tukwila International Boulevard station to the RapidRide F Line bus service.{{cite web |title=Going to SeaTac from Tukwila Station |url=http://www.amtrakcascades.com/sites/default/files/TukwilaToSeaTac.pdf |url-status=live |archive-url=https://web.archive.org/web/20170614195805/http://www.amtrakcascades.com/sites/default/files/TukwilaToSeaTac.pdf |archive-date=June 14, 2017 |access-date=October 5, 2017 |publisher=Amtrak Cascades}}

The airport serves door-to-door shuttle services (Shuttle Express and Speedi Shuttle) and several scheduled airporter bus services. Airporters include Bellair Charters to Yakima and Bellingham, and the Quick Shuttle to downtown Vancouver, Canada, through Quick Shuttle, with other pick-up stops at downtown Seattle, Bellingham International Airport, and drop-off stops just inside the Canadian–U.S. boundary and at the Vancouver International Airport.{{cite web |title=Quick Shuttle: Vancouver to/from Seattle |url=http://www.quickcoach.com/schedule.htm |url-status=live |archive-url=https://web.archive.org/web/20120621045330/http://www.quickcoach.com/schedule.htm |archive-date=June 21, 2012 |access-date=July 3, 2012 |website=Quick Shuttle}}

Taxis, limousines, and transportation network companies (Lyft, Uber and Wingz) are also available.{{cite web |title=Public Transit |url=https://www.portseattle.org/Sea-Tac/Parking-and-Transportation/Ground-Transportation/Pages/Public-Transit.aspx |url-status=dead |archive-url=https://web.archive.org/web/20151230143908/http://www.portseattle.org/Sea-Tac/Parking-and-Transportation/Ground-Transportation/Pages/Public-Transit.aspx |archive-date=December 30, 2015 |access-date=July 3, 2012 |website=Port of Seattle}} Prior to 2019, the Port of Seattle contracted out taxi services to an independent company, but changed to direct management with drivers due to protests over high access fees. {{As of|2023}}, the airport has 409 taxi drivers who are part of the Teamsters Local 117 labor union.{{cite news |last=Girgis |first=Lauren |date=February 13, 2023 |title=As taxi business wanes at Sea-Tac, drivers want a say in their future |url=https://www.seattletimes.com/seattle-news/as-taxi-business-wanes-at-sea-tac-drivers-want-a-say-in-their-future/ |work=The Seattle Times |access-date=February 16, 2023 |archive-date=February 17, 2023 |archive-url=https://web.archive.org/web/20230217063533/https://www.seattletimes.com/seattle-news/as-taxi-business-wanes-at-sea-tac-drivers-want-a-say-in-their-future/ |url-status=live }}

A {{convert|23|acre|ha|adj=on}} consolidated rental car facility opened on May 17, 2012.{{cite web |date=May 6, 2012 |title=Rental Car Facility Breaks the Ribbon Before Opening Under Budget |url=https://www.portseattle.org/Newsroom/News-Releases/Pages/default.aspx?year=2012#283 |url-status=dead |archive-url=https://web.archive.org/web/20120526221600/http://www.portseattle.org/Newsroom/News-Releases/Pages/default.aspx?year=2012#283 |archive-date=May 26, 2012 |access-date=May 18, 2012 |website=Port of Seattle}}{{cite web |title=Consolidated Rental Car Facility |url=https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Pages/Consolidated-Rental-Car-Facility.aspx |url-status=dead |archive-url=https://web.archive.org/web/20170107003849/https://www.portseattle.org/Business/Construction-Projects/Airport-Projects/Pages/Consolidated-Rental-Car-Facility.aspx |archive-date=January 7, 2017 |access-date=November 8, 2012 |publisher=Port of Seattle }} The facility is at the northeastern portion of the airport at the intersection of South 160th Street and International Boulevard South. The facility has 5,400 parking spaces{{Cite news |last=Gillie |first=John |date=May 10, 2012 |title=Rental Car Facility to Open at Sea-Tac |work=The News Tribune |url=http://www.thenewstribune.com/2012/05/10/2138358/airport-car-rental-site-to-open.html |url-status=dead |access-date=May 18, 2012 |archive-url=https://web.archive.org/web/20120529133551/http://www.thenewstribune.com/2012/05/10/2138358/airport-car-rental-site-to-open.html |archive-date=May 29, 2012}} and can handle up to 14,000 transactions per day. After the opening of the facility, 3,200 parking spaces in the central parking structure opened for general use.{{Cite news |last=Cohen |first=Aubrey |date=June 14, 2010 |title=Sea-Tac Airport Tops Off Rental Car Facility |work=Seattle Post-Intelligencer |url=http://blog.seattlepi.com/aerospace/archives/214590.asp |url-status=dead |access-date=June 14, 2010 |archive-url=https://web.archive.org/web/20121104155019/http://blog.seattlepi.com/aerospace/2010/07/14/sea-tac-airport-tops-off-rental-car-facility/ |archive-date=November 4, 2012}} Passengers reach the facility on a five-minute trip aboard one of 29 low-floor Gillig CNG buses. Previously, only Alamo, Avis, Sixt, Budget, Hertz and National had cars on site. Advantage, Dollar, Enterprise, Thrifty, EZ Rent-A-Car and Fox Rent A Car ran shuttles to off-site locations. {{As of|2012}}, Rent-a-Wreck was the last remaining company to not relocate to the consolidated facility and continue using their own shuttles.

{{Airport destination list | 3rdcoltitle = Refs | 3rdcolunsortable=yes

| Aer Lingus | Dublin | {{cite web|url=https://www.aerlingus.com/html/flights-time-table.html|title=Aer Lingus Timetable|website=aerlingus.com|access-date=October 5, 2021|archive-date=February 19, 2017|archive-url=https://web.archive.org/web/20170219100623/https://www.aerlingus.com/html/flights-time-table.html|url-status=live}}

| Aeroméxico | Mexico City | {{cite web |title=Flight Schedule |url=https://booking.aeromexico.com/SSW2010/D5DE/flightSchedulePage.html?_ga=1.18768702.686413547.1491325115 |url-status=live |archive-url=https://web.archive.org/web/20170406022455/https://booking.aeromexico.com/SSW2010/D5DE/flightSchedulePage.html?_ga=1.18768702.686413547.1491325115 |archive-date=April 6, 2017 |access-date=March 24, 2018}}

| Air Canada | Toronto–Pearson
Seasonal: Montréal–Trudeau | {{cite web |title=Flight Schedules |url=https://www.aircanada.com/ca/en/aco/home/book/routes-and-partners/flight-schedules.html |url-status=live |archive-url=https://web.archive.org/web/20180323072516/https://www.aircanada.com/ca/en/aco/home/book/routes-and-partners/flight-schedules.html |archive-date=March 23, 2018 |access-date=March 24, 2018 |publisher=Air Canada}}

| {{nowrap|Air Canada Express}} | Vancouver |

| {{nowrap|Air France}} | Paris–Charles de Gaulle | {{cite web|url=https://wwws.airfrance.us/travel-guide/destinations/america/united-states/seattle|title=Our destinations|publisher=Air France|access-date=January 11, 2025|archive-date=January 12, 2025|archive-url=https://web.archive.org/web/20250112062611/https://wwws.airfrance.us/travel-guide/destinations/america/united-states/seattle|url-status=live}}

| {{nowrap|Air Tahiti Nui}} | Papeete | {{cite web|url=https://www.alaskaair.com/content/mileage-plan/how-to-earn-miles/airline-partners/air-tahiti-nui|title=Alaska Partner – Air Tahiti Nui|publisher=Alaska Air Group|location=Seattle|website=Alaska Airlines|access-date=March 29, 2022|archive-date=October 22, 2023|archive-url=https://web.archive.org/web/20231022065517/https://www.alaskaair.com/content/mileage-plan/how-to-earn-miles/airline-partners/air-tahiti-nui|url-status=live}}

| Alaska Airlines | Albuquerque, Anchorage, Atlanta, Austin, Baltimore, Bellingham, Billings, Boise, Boston, Bozeman, Burbank, Calgary, Cancún, Charleston (SC), Chicago–O'Hare, Cincinnati, Cleveland, Columbus–Glenn, Dallas/Fort Worth, Dallas–Love (ends May 14, 2025),{{cite web |last1=Snyder |first1=Rachel |title=Alaska Airlines is leaving Dallas Love Field airport |url=https://www.wfaa.com/article/travel/alaska-airlines-ending-service-dallas-love-field/287-5329beef-d715-4644-a026-c2a5c5d85ade |website=WFAA |access-date=11 February 2025}} Denver, Detroit, Edmonton, El Paso, Eugene, Fairbanks, Fort Lauderdale, Fresno, Glacier Park/Kalispell, Great Falls, Helena, Honolulu, Houston–Intercontinental, Idaho Falls, Indianapolis, Jackson Hole, Juneau, Kahului, Kailua-Kona, Kansas City, Kelowna, Ketchikan, Las Vegas, Lihue, Los Angeles, Medford, Miami, Milwaukee, Minneapolis/St. Paul, Missoula, Monterey, Nashville, Newark, New Orleans, New York–JFK, Oakland, Oklahoma City, Omaha, Ontario, Orange County, Orlando, Palm Springs, Philadelphia, Phoenix–Sky Harbor, Pittsburgh, Portland (OR), Puerto Vallarta, Pullman, Raleigh/Durham, Redding, Redmond/Bend, Reno/Tahoe, Sacramento, St. Louis, Salt Lake City, San Antonio, San Diego, San Francisco, San Jose (CA), San José del Cabo, San Luis Obispo, Santa Barbara, Santa Rosa, Spokane, Sun Valley, Tampa, Toronto–Pearson,{{cite web |title=Alaska Airlines Schedules mid-May 2024 Toronto Launch |url=https://www.aeroroutes.com/eng/240120-asns24yyz |website=Aeroroutes |access-date=January 20, 2024 |archive-date=January 20, 2024 |archive-url=https://web.archive.org/web/20240120020118/https://www.aeroroutes.com/eng/240120-asns24yyz |url-status=live }} Tri-Cities (WA), Tucson, Vancouver, Victoria, Walla Walla, Washington–Dulles, Washington–National, Wenatchee, Wichita, Yakima
Seasonal: Belize City, Eagle/Vail,{{cite web|url=https://airlinegeeks.com/2024/07/10/alaska-adds-18-new-routes/|title=Alaska Adds 18 New Routes|website=Airline Geeks|date=July 10, 2024|access-date=July 10, 2024|archive-date=July 10, 2024|archive-url=https://web.archive.org/web/20240710151001/https://airlinegeeks.com/2024/07/10/alaska-adds-18-new-routes/|url-status=live}} Fort Myers, Hayden/Steamboat Springs, Liberia (CR), Sitka | {{cite news |title = Flight Timetable |newspaper = Alaska Airlines |url = https://www.alaskaair.com/content/travel-info/timetables.aspx |access-date = March 23, 2018 |archive-url = https://web.archive.org/web/20170202123138/https://www.alaskaair.com/content/travel-info/timetables.aspx |archive-date = February 2, 2017 |url-status = live |last1 = Airlines |first1 = Alaska }}

| All Nippon Airways | Tokyo–Haneda | {{cite web |title=Timetables [International Routes] |url=https://www.ana.co.jp/en/us/book-plan/airinfo/timetable/international/ |url-status=live |archive-url=https://web.archive.org/web/20180624092943/https://www.ana.co.jp/en/us/book-plan/airinfo/timetable/international/ |archive-date=June 24, 2018 |access-date=March 24, 2018}}

| American Airlines | Charlotte, Chicago–O'Hare, Dallas/Fort Worth, Miami, Philadelphia
Seasonal: Phoenix–Sky Harbor | {{cite web |title=Flight schedules and notifications |url=https://www.aa.com/travelInformation/flights/schedule |url-status=live |archive-url=https://web.archive.org/web/20170202010611/https://www.aa.com/travelInformation/flights/schedule |archive-date=February 2, 2017 |access-date=December 4, 2024}}

| American Eagle | Los Angeles, Phoenix–Sky Harbor |

| Asiana Airlines | Seoul–Incheon | {{cite web |title=Routes of Service |url=http://us.flyasiana.com/C/en/homepage.do?menuId=001012000000000&menuType=CMS |url-status=dead |archive-url=https://web.archive.org/web/20180317232749/http://us.flyasiana.com/C/en/homepage.do?menuId=001012000000000&menuType=CMS |archive-date=March 17, 2018 |access-date=March 24, 2018}}

| British Airways | London–Heathrow | {{cite web |title=British Airways – Timetables |url=https://www.britishairways.com/travel/schedules/public/en_us |url-status=live |archive-url=https://web.archive.org/web/20170227150150/https://www.britishairways.com/travel/schedules/public/en_us |archive-date=February 27, 2017 |access-date=March 24, 2018}}

| China Airlines | Taipei–Taoyuan | {{cite web|url= https://www.aeroroutes.com/eng/240312-cijul24sea|title=CHINA AIRLINES RESUMES TAIPEI – SEATTLE SERVICE FROM JULY 2024|publisher=AeroRoutes|date=March 11, 2024|accessdate=March 11, 2024}}

| Condor | Frankfurt | [https://www.condor.com/de/generated/flugplan_S2020.pdf condor.com – Flugplan Sommer 2020] {{Webarchive|url=https://web.archive.org/web/20230813120443/https://www.condor.com/de/generated/flugplan_S2020.pdf |date=August 13, 2023 }} (German) retrieved June 8, 2020

| Delta Air Lines | Amsterdam, Anchorage, Atlanta, Austin, Boston, Cancún, Chicago–O'Hare, Cincinnati, Dallas/Fort Worth,{{cite web|title=Santa Barbara, Yosemite, Tahoe and more: Get there on Delta with new and returning flights for summer 2024|url=https://news.delta.com/santa-barbara-yosemite-tahoe-and-more-get-there-delta-new-and-returning-flights-summer-2024|access-date=September 15, 2023|website=Delta News Hub|date=September 15, 2023|archive-date=October 31, 2023|archive-url=https://web.archive.org/web/20231031184838/https://news.delta.com/santa-barbara-yosemite-tahoe-and-more-get-there-delta-new-and-returning-flights-summer-2024|url-status=live}} Denver, Detroit, Fairbanks, Fort Lauderdale, Honolulu, Kahului, Kailua-Kona, Kansas City, Las Vegas, Lihue, London–Heathrow, Los Angeles, Miami,{{cite web |title=Delta deepens leisure footprint with new routes to Hawaii and Miami|url= https://news.delta.com/delta-deepens-leisure-footprint-new-routes-hawaii-and-miami|website=Delta News Hub|date= February 16, 2024}} Minneapolis/St. Paul, Nashville, New York–JFK, Orange County, Orlando, Paris–Charles de Gaulle, Phoenix–Sky Harbor, Portland (OR), Puerto Vallarta, Raleigh/Durham, Sacramento, Salt Lake City, San Diego, San Francisco, San José del Cabo, Seoul–Incheon, Shanghai–Pudong, Spokane, Taipei–Taoyuan,{{cite web |title=Delta to fly to Taipei from Seattle hub |url=https://news.delta.com/delta-fly-taipei-seattle-hub |website=Delta News Hub |date=December 7, 2023 |access-date=December 7, 2023 |archive-date=December 7, 2023 |archive-url=https://web.archive.org/web/20231207180956/https://news.delta.com/delta-fly-taipei-seattle-hub |url-status=live }} Tampa, Tokyo–Haneda, Washington–Dulles, Washington–National{{cite web |title=Delta launches nonstop Washington D.C. to Seattle service March 2025 |url=https://news.delta.com/delta-launches-nonstop-washington-dc-seattle-service-march-2025 |website=Delta News Hub |date=December 19, 2024 |access-date=December 19, 2024 |archive-date=December 19, 2024 |archive-url=https://web.archive.org/web/20241219203935/https://news.delta.com/delta-launches-nonstop-washington-dc-seattle-service-march-2025 |url-status=live }}
Seasonal: Juneau, Palm Springs | {{cite web |title = Flight schedules |url = https://www.delta.com/flightinfo/viewFlightSchedulesSetup.action |access-date = March 17, 2018 |archive-url = https://web.archive.org/web/20150621123636/http://www.delta.com/flightinfo/viewFlightSchedulesSetup.action |archive-date = June 21, 2015 |url-status = live }}

| Delta Connection | Boise, Bozeman (resumes June 30, 2025),{{Cite web |url=https://bozemanairport.com/blog/deltayearroundsea2025 |title=Archived copy |access-date=February 12, 2025 |archive-date=January 14, 2025 |archive-url=https://web.archive.org/web/20250114125924/https://bozemanairport.com/blog/deltayearroundsea2025 |url-status=live }} Denver, Eugene, Lewiston,{{cite web | url=https://www.bigcountrynewsconnection.com/idaho/lewiston-airport-to-offer-flights-to-seattle-beginning-october-9/article_f026cb4e-387e-11ee-a99b-872e4d75277d.html | title=Lewiston Airport to Offer Flights to Seattle Beginning October 9 | date=August 11, 2023 | access-date=August 12, 2023 | archive-date=August 16, 2023 | archive-url=https://web.archive.org/web/20230816185540/https://www.bigcountrynewsconnection.com/idaho/lewiston-airport-to-offer-flights-to-seattle-beginning-october-9/article_f026cb4e-387e-11ee-a99b-872e4d75277d.html | url-status=live }} Medford, Ontario, Orange County, Portland (OR), Redmond/Bend, Sacramento, San Francisco, San Jose (CA), Spokane, Tri-Cities (WA), Tucson, Vancouver
Seasonal: Sun Valley{{cite web |title=Delta Expands Bozeman Service in NW24; Resumes Seattle – Sun City Service |url=https://www.aeroroutes.com/eng/241001-dlnw24bznsun |website=Aeroroutes |access-date=1 October 2024 |archive-date=October 1, 2024 |archive-url=https://web.archive.org/web/20241001202557/https://www.aeroroutes.com/eng/241001-dlnw24bznsun |url-status=live }} |

| Edelweiss Air | Seasonal: Zurich (begins June 2, 2025) | {{cite web |title= SEA Welcomes Announcement of Edelweiss Air's New Service to Zurich |url= https://www.portseattle.org/news/sea-welcomes-announcement-edelweiss-airs-new-service-zurich |access-date= August 13, 2024 |publisher= Port Of Seattle |archive-date= August 13, 2024 |archive-url= https://web.archive.org/web/20240813185646/https://www.portseattle.org/news/sea-welcomes-announcement-edelweiss-airs-new-service-zurich |url-status= live }}

| Emirates | Dubai–International | {{cite web |title=Flight Schedules |url=https://www.emirates.com/ca/english/destinations_offers/timetables/flightschedule.aspx |url-status=live |archive-url=https://web.archive.org/web/20170630185434/https://www.emirates.com/ca/english/destinations_offers/timetables/flightschedule.aspx |archive-date=June 30, 2017 |access-date=March 24, 2018 |publisher=Emirates}}

| EVA Air | Taipei–Taoyuan | {{cite web |title=Timetables |url=https://booking.evaair.com/flyeva/EVA/B2C/flight-schedules.aspx |url-status=live |archive-url=https://web.archive.org/web/20170516001221/http://booking.evaair.com/flyeva/EVA/B2C/flight-schedules.aspx |archive-date=May 16, 2017 |access-date=March 24, 2018 |publisher=EVA Air}}

| Finnair | Seasonal: Helsinki | {{cite web |title=Flights to Finnair destinations {{!}} Finnair United States |url=https://www.finnair.com/us-en/destinations |website=www.finnair.com |access-date=November 9, 2021 |archive-date=May 22, 2023 |archive-url=https://web.archive.org/web/20230522171104/https://www.finnair.com/us-en/destinations |url-status=live }}

| Frontier Airlines | Dallas/Fort Worth,{{cite web |title=Frontier Airlines Announces New Routes, Expanding Operations Across 12 Airports |url=https://news.flyfrontier.com/frontier-airlines-announces-new-routes-expanding-operations-across-12-airports/ |website=Frontier Airlines |access-date=April 4, 2024 |archive-date=April 4, 2024 |archive-url=https://web.archive.org/web/20240404182406/https://news.flyfrontier.com/frontier-airlines-announces-new-routes-expanding-operations-across-12-airports/ |url-status=live }} Denver, Las Vegas, Los Angeles,{{cite web |title=Frontier Airlines Announces 22 New Routes Across US |url=https://www.travelpulse.com/news/airlines-airports/frontier-airlines-announces-22-new-routes-across-us |website=Travel Pulse |access-date=October 1, 2024 |archive-date=December 26, 2024 |archive-url=https://web.archive.org/web/20241226055055/https://www.travelpulse.com/news/airlines-airports/frontier-airlines-announces-22-new-routes-across-us |url-status=live }} Ontario,{{cite web |title=Frontier Airlines Announces 17 New Routes Across Multiple Airports, Spanning the U.S. and Caribbean |url=https://news.flyfrontier.com/frontier-airlines-announces-17-new-routes-across-multiple-airports--spanning-the-us-and-caribbean/ |website=Frontier Airlines |access-date=February 28, 2024 |archive-date=February 28, 2024 |archive-url=https://web.archive.org/web/20240228193206/https://news.flyfrontier.com/frontier-airlines-announces-17-new-routes-across-multiple-airports--spanning-the-us-and-caribbean/ |url-status=live }} Phoenix–Sky Harbor, Salt Lake City{{cite web|url=https://www.travelpulse.com/news/airlines-airports/frontier-airlines-unveils-new-routes-for-fall|title=Frontier Airlines Unveils New Routes for Fall|website=Travel Pulse|access-date=August 27, 2024|archive-date=September 25, 2024|archive-url=https://web.archive.org/web/20240925122340/https://www.travelpulse.com/news/airlines-airports/frontier-airlines-unveils-new-routes-for-fall|url-status=live}} | {{cite web|title=Frontier|url=https://www.flyfrontier.com|access-date=January 7, 2017|archive-url=https://web.archive.org/web/20170912053526/https://www.flyfrontier.com/|archive-date=September 12, 2017|url-status=live}}

| Hainan Airlines | Beijing–Capital, Chongqing{{cite web|url=https://www.aeroroutes.com/eng/240403-humay24ckgsea|title=Hainan Airlines Adds Chongqing - Seattle From mid-May 2024|publisher=AeroRoutes|date=2 April 2024|accessdate=2 April 2024|archive-date=April 3, 2024|archive-url=https://web.archive.org/web/20240403034300/https://www.aeroroutes.com/eng/240403-humay24ckgsea|url-status=live}} | {{cite web|url=https://www.aeroroutes.com/eng/240320-huns24sea|title=Hainan Airlines Resumes Beijing - Seattle Service in April 2024|publisher=AeroRoutes|date=20 March 2024|accessdate=20 March 2024|archive-date=March 20, 2024|archive-url=https://web.archive.org/web/20240320042634/https://www.aeroroutes.com/eng/240320-huns24sea|url-status=live}}

| Hawaiian Airlines | Honolulu, Kahului, Seoul–Incheon (begins September 12, 2025),{{cite web |url=https://www.travelandtourworld.com/news/article/alaska-airlines-partners-with-hawaiian-airlines-to-launch-direct-service-from-seattle-to-seoul-incheon-just-in-time-for-the-2025-chuseok-festival/amp/ |title=Alaska Airlines Partners with Hawaiian Airlines to Launch Direct Service from Seattle to Seoul Incheon Just in Time for the 2025 Chuseok Festival |website=Travel and Tour World |access-date=25 March 2025 }} Tokyo–Narita (begins May 12, 2025){{cite news |url=https://www.king5.com/article/travel/alaska-airlines-nonstop-flight-seattle-tokyo-seoul/281-8732da98-f1fc-4151-88c9-03efd5fd748c|title=Alaska Airlines adds nonstop flights from Seattle to Tokyo and Seoul|work=KING 5 News|first=Helen|last=Smith|date=December 10, 2024|access-date=December 10, 2024 }}
Seasonal: Anchorage (begins June 12, 2025){{cite web |title=Hawaiian Airlines NS25 Network Adjustments – 11DEC24 |url=https://www.aeroroutes.com/eng/241211-hans25 |website=Aeroroutes |access-date=11 December 2024 |archive-date=December 11, 2024 |archive-url=https://web.archive.org/web/20241211045559/https://www.aeroroutes.com/eng/241211-hans25 |url-status=live }} | {{cite web |title=Destinations |url=https://www.hawaiianairlines.com/destinations |url-status=live |archive-url=https://web.archive.org/web/20180129192310/https://www.hawaiianairlines.com/destinations |archive-date=January 29, 2018 |access-date=March 24, 2018}}

| Icelandair | Reykjavík–Keflavík | {{cite web |title=Flight Schedule |url=http://www.icelandair.ca/information/travel-guide/timetable/ |url-status=live |archive-url=https://web.archive.org/web/20171116064841/http://www.icelandair.ca/information/travel-guide/timetable/ |archive-date=November 16, 2017 |access-date=March 24, 2018 |publisher=Icelandair}}

| Japan Airlines | Tokyo–Narita | {{cite web |title=Japan Airlines Timetables |url=http://www.jal.co.jp/en/inter/route/time/ |url-status=live |archive-url=https://web.archive.org/web/20181015202347/http://www.jal.co.jp/en/inter/route/time/ |archive-date=October 15, 2018 |access-date=March 24, 2018}}

| JetBlue | Boston
Seasonal: New York–JFK | {{cite web |title=JetBlue New Routes |url=http://mediaroom.jetblue.com/investor-relations/press-releases/2021/02-18-2021-160050512 |access-date=July 10, 2021 |archive-date=August 15, 2023 |archive-url=https://web.archive.org/web/20230815184835/https://mediaroom.jetblue.com/investor-relations/press-releases/2021/02-18-2021-160050512/ |url-status=dead }}

| Korean Air | Seoul–Incheon | {{cite web |title=Flight Status and Schedules |url=https://www.koreanair.com/global/en/booking/schedule-flight.html#schedule |url-status=live |archive-url=https://web.archive.org/web/20180628234008/https://www.koreanair.com/global/en/booking/schedule-flight.html#schedule |archive-date=June 28, 2018 |access-date=March 24, 2018 |publisher=Korean Air}}

| Lufthansa | Frankfurt, Munich{{cite web|url=https://www.portseattle.org/news/sea-grows-international-gateway-lufthansa-service-munich|title=SEA Grows International Gateway with Lufthansa Service to Munich|website=Port of Seattle|date=September 12, 2023|access-date=September 12, 2023|archive-date=October 10, 2023|archive-url=https://web.archive.org/web/20231010191920/https://www.portseattle.org/news/sea-grows-international-gateway-lufthansa-service-munich|url-status=live}} | {{cite web |title=Timetable – Lufthansa USA |url=http://www.lufthansa.com/ca/en/Online-timetable |url-status=live |archive-url=https://web.archive.org/web/20171109191434/http://www.lufthansa.com/us/en/Online-timetable |archive-date=November 9, 2017 |access-date=March 24, 2018 |publisher=Lufthansa}}

| Philippine Airlines | Manila | {{cite web|url=https://www.portseattle.org/news/sea-airport-welcomes-philippine-airlines-nonstop-service-manila|title=Mabuhay! SEA Welcomes Announcement of Nonstop Service to Manila on Philippine Airlines|website=Port of Seattle|date=April 1, 2024|access-date=April 30, 2024|archive-date=April 30, 2024|archive-url=https://web.archive.org/web/20240430123435/https://www.portseattle.org/news/sea-airport-welcomes-philippine-airlines-nonstop-service-manila|url-status=live}}

| Qatar Airways | Doha | {{Cite press release |date=December 8, 2020 |title=Qatar Airways to Launch Flights to Seattle from 15 March 2021, Marking Second New U.S. Destination Announced This Year |publisher=Qatar Airways |location=Doha |url=https://www.qatarairways.com/en/press-releases/2020/december/SEA-AS.html?activeTag=Press-releases |access-date=December 8, 2020 |archive-date=August 13, 2023 |archive-url=https://web.archive.org/web/20230813120600/https://www.qatarairways.com/en/press-releases/2020/december/SEA-AS.html?activeTag=Press-releases |url-status=live }}

| {{nowrap|Scandinavian Airlines}} | Seasonal: Copenhagen (begins May 21, 2025) | {{Cite web|title=SAS resumes Copenhagen-Seattle service from May 2025|website=aeroroutes.com|url=https://www.aeroroutes.com/eng/240917-skns25sea/|date=17 September 2024|access-date=September 17, 2024|archive-date=September 17, 2024|archive-url=https://web.archive.org/web/20240917113104/https://www.aeroroutes.com/eng/240917-skns25sea/|url-status=live}}

| Singapore Airlines | Singapore | {{Cite press release |title=Singapore Airlines Announces Nonstop Service to Sea-Tac Airport |date=October 31, 2018 |publisher=Port of Seattle |location=Seattle|last=Cooper|first=Perry|url=https://www.portseattle.org/news/singapore-airlines-announces-nonstop-service-sea-tac-airport |access-date=October 31, 2018 |url-status=live |archive-url=https://web.archive.org/web/20181101135901/https://www.portseattle.org/news/singapore-airlines-announces-nonstop-service-sea-tac-airport |archive-date=November 1, 2018}}

| Southwest Airlines | Chicago–Midway, Denver, Las Vegas, Oakland, Phoenix–Sky Harbor, Sacramento, San Jose (CA)
Seasonal: Baltimore,{{Cite press release |date=October 27, 2023 |title=More Heart than ever before. |publisher=Southwest Airlines |location=Dallas |url=https://wieck-swa-production.s3-us-west-1.amazonaws.com/page-d5bda4d2c147f577fd1d8c167c4e5464/attachment/7edddc9c03df0fbe3e70f808a2345f236b0f15ba |access-date=October 27, 2023 |archive-date=November 1, 2023 |archive-url=https://web.archive.org/web/20231101194653/https://wieck-swa-production.s3-us-west-1.amazonaws.com/page-d5bda4d2c147f577fd1d8c167c4e5464/attachment/7edddc9c03df0fbe3e70f808a2345f236b0f15ba |url-status=live }} Dallas–Love, Houston–Hobby (resumes June 5, 2025),{{cite web |title=Southwest Airlines offers new overnight flights, including Seattle to Houston next year |url=https://www.houstonchronicle.com/news/houston-texas/transportation/article/southwest-airlines-redeye-houston-19876977.php |website=Houston Chronicle |access-date=October 31, 2024 |archive-date=November 13, 2024 |archive-url=https://web.archive.org/web/20241113132813/https://www.houstonchronicle.com/news/houston-texas/transportation/article/southwest-airlines-redeye-houston-19876977.php |url-status=live }} Kansas City, Nashville, St. Louis | {{cite web |title = Check Flight Schedules |url = https://www.southwest.com/air/flight-schedules/index.html |access-date = March 23, 2018 |archive-url = https://web.archive.org/web/20170202053931/https://www.southwest.com/air/flight-schedules/index.html |archive-date = February 2, 2017 |url-status = live }}

| Spirit Airlines | Las Vegas, Los Angeles{{cite web|last=Liu|first=Jim|url=https://www.aeroroutes.com/eng/240416-nkjul24lax|title=Spirit Airlines Resumes LAX-Pacific Northwest Service From July 2024|website=AeroRoutes|access-date=April 16, 2024|archive-date=April 16, 2024|archive-url=https://web.archive.org/web/20240416211448/https://www.aeroroutes.com/eng/240416-nkjul24lax|url-status=live}} | {{cite web |title = Where We Fly |url = https://www.spirit.com/RouteMaps.aspx |publisher = Spirit Airlines |access-date = March 23, 2018 |archive-url = https://web.archive.org/web/20171223042503/https://www.spirit.com/routemaps.aspx |archive-date = December 23, 2017 |url-status = live |df = dmy-all }}

| Starlux Airlines | Taipei–Taoyuan | {{cite web|url=https://www.aeroroutes.com/eng/240307-jxaug24sea|title=Starlux Airlines Schedules mid-August 2024 Seattle Launch|publisher=AeroRoutes|access-date=March 7, 2024}}

| {{nowrap|Sun Country Airlines}} | Minneapolis/St. Paul | {{cite web |title = Route Map & Flight Schedule |url = https://www.suncountry.com/Explore/Route-Map.html |access-date = January 7, 2017 |archive-url = https://web.archive.org/web/20180815090927/https://www.suncountry.com/Explore/Route-Map.html |archive-date = August 15, 2018 |url-status = live }}

| Turkish Airlines | Istanbul | {{cite web |url=https://www.turkishairlines.com/en-us/flights/ |title=Online Flight Schedule |publisher=Turkish Airlines |access-date=April 25, 2023 |archive-date=April 10, 2019 |archive-url=https://web.archive.org/web/20190410174518/https://www.turkishairlines.com/en-us/flights/ |url-status=live }}

| United Airlines | Chicago–O'Hare, Denver, Houston–Intercontinental, Los Angeles, Newark, San Francisco, Washington–Dulles | {{cite web |title = Timetable |url = https://www.united.com/web/en-US/apps/travel/timetable/default.aspx |access-date = March 23, 2018 |archive-url = https://web.archive.org/web/20170128165254/https://www.united.com/web/en-US/apps/travel/timetable/default.aspx |archive-date = January 28, 2017 |url-status = live }}

| Virgin Atlantic | London–Heathrow | {{cite web |title = Interactive flight map |url = http://vs.fltmaps.com/en/gb |access-date = March 29, 2017 |archive-url = https://web.archive.org/web/20180424150818/http://vs.fltmaps.com/en/gb |archive-date = April 24, 2018 |url-status = dead }}

| Volaris | Guadalajara | {{cite news |last=Phair |first=Vonnai |date=June 14, 2021 |title=Travelers can fly nonstop to 16 world destinations from Seattle — but should you? Know the COVID rules, risks |url=https://www.seattletimes.com/life/travel/here-are-the-16-destinations-you-can-fly-nonstop-to-from-seattle-and-their-latest-covid-19-travel-advisories/ |work=The Seattle Times |accessdate=December 3, 2023 |archive-date=December 4, 2023 |archive-url=https://web.archive.org/web/20231204044838/https://www.seattletimes.com/life/travel/here-are-the-16-destinations-you-can-fly-nonstop-to-from-seattle-and-their-latest-covid-19-travel-advisories/ |url-status=live }}

| WestJet | Calgary | {{cite web |title = Flight schedules |url = https://www.westjet.com/en-ca/travel-info/flight-info/flight-schedules |access-date = March 17, 2018 |archive-url = https://web.archive.org/web/20170210131344/https://www.westjet.com/en-ca/travel-info/flight-info/flight-schedules |archive-date = February 10, 2017 |url-status = live }}

| WestJet Encore | Kelowna{{cite web|url=https://www.westjet.com/en-ca/news/2024/westjet-announces-new-daily-service-between-kelowna-and-seattle-/|title=WestJet announces new daily service between Kelowna and Seattle beginning this winter|publisher=WestJet|date=July 24, 2024|accessdate=July 25, 2024|archive-date=July 27, 2024|archive-url=https://web.archive.org/web/20240727043654/https://www.westjet.com/en-ca/news/2024/westjet-announces-new-daily-service-between-kelowna-and-seattle-|url-status=live}}
Seasonal: Edmonton | {{cite press release |url=https://www.portseattle.org/news/sea-welcomes-westjet-inaugural-flight-new-service-calgary |title=SEA Welcomes WestJet Inaugural Flight with New Service to Calgary |last=Cooper |first=Perry |publisher=Port of Seattle |location=Seattle|date=November 5, 2021 |url-status=live |archive-url=https://web.archive.org/web/20211107024856/https://www.portseattle.org/news/sea-welcomes-westjet-inaugural-flight-new-service-calgary |archive-date=November 7, 2021 |access-date=November 6, 2021 }}

}}

{{more citations needed|section|date=August 2020}}

{{Airport destination list|3rdcoltitle={{Abbr|Refs.|References}}|3rdcolunsortable=yes

| AeroLogic | Frankfurt | {{cite web |title=The customized AeroLogic network |url=https://www.aerologic.aero/home#tab-3 |website=Aerologic |access-date=May 14, 2024 |archive-date=March 16, 2023 |archive-url=https://web.archive.org/web/20230316073834/https://www.aerologic.aero/home#tab-3 |url-status=live }}

| Alaska Air Cargo | Anchorage, Cordova,{{cn|date=May 2024}} Juneau, Ketchikan, Los Angeles, Petersburg, Sitka,{{cn|date=May 2024}} Wrangell, Yakutat{{cn|date=May 2024}} | {{cite web |title=Freighter Schedule |url=https://www.alaskacargo.com/services/freighter-schedule |website=Alaska Air Cargo |publisher=Alaska Airlines, Inc. |access-date=May 14, 2024 |archive-date=May 14, 2024 |archive-url=https://web.archive.org/web/20240514185712/https://www.alaskacargo.com/services/freighter-schedule |url-status=live }}

| Aloha Air Cargo | Honolulu, Los Angeles{{cn|date=May 2024}} | {{cite web|title=Service Schedule|url=https://www.alohaaircargo.com/service-schedule/|access-date=May 14, 2024|publisher=Aloha Air Cargo|archive-date=August 13, 2023|archive-url=https://web.archive.org/web/20230813120121/https://www.alohaaircargo.com/service-schedule/|url-status=live}}

| Amazon Air | Allentown,{{cn|date=May 2024}} Anchorage,{{cn|date=May 2024}} Chicago–O'Hare, Cincinnati, Hartford,{{cn|date=May 2024}} Los Angeles, Miami, New York–JFK,{{cn|date=May 2024}} Ontario,{{cn|date=May 2024}} Riverside, San Bernardino,{{cn|date=May 2024}} Wilmington (OH) | {{cite web |last1=Schwieterman |first1=Joseph P. |last2=Morgado |first2=Borja G. |last3=Mader |first3=Abby |title=Total Package: Amazon Air's Changing Network & Strategic Orientation |url=https://las.depaul.edu/centers-and-institutes/chaddick-institute-for-metropolitan-development/research-and-publications/Documents/Total%20Package%20Amazon%20Air%27s%20Changing%20Network%20and%20Strategic%20Orientation.pdf |publisher=DePaul College of Liberal Arts and Social Sciences Chaddick Institute for Metropolitan Development |access-date=May 14, 2024 |archive-date=May 14, 2024 |archive-url=https://web.archive.org/web/20240514185713/https://las.depaul.edu/centers-and-institutes/chaddick-institute-for-metropolitan-development/research-and-publications/Documents/Total%20Package%20Amazon%20Air%27s%20Changing%20Network%20and%20Strategic%20Orientation.pdf |url-status=live }}

| Ameriflight | Moses Lake, Spokane | {{cite web |title=Fleet Bases |url=https://w3.ameriflight.com/fleet-bases/ |website=Ameriflight |access-date=May 14, 2024 |archive-date=April 13, 2018 |archive-url=https://web.archive.org/web/20180413043404/https://w3.ameriflight.com/fleet-bases/ |url-status=live }}

| Asiana Cargo | Chicago–O'Hare, Dallas/Fort Worth, Seoul–Incheon | {{cn|date=May 2024}}

| Cargolux | Calgary,{{cn|date=May 2024}} Glasgow–Prestwick, Los Angeles,{{cn|date=May 2024}} Luxembourg | {{cite web |title=Cargolux Network |url=https://www.cargolux.com/network/ |website=Cargolux |access-date=May 14, 2024 |archive-date=June 17, 2024 |archive-url=https://web.archive.org/web/20240617231217/https://www.cargolux.com/network/ |url-status=live }}

| China Airlines Cargo | Anchorage, Chicago–O'Hare, Columbus–Rickenbacker, Miami, New York–JFK, Taipei–Taoyuan | {{cn|date=May 2024}}

| DHL Aviation | Cincinnati, Los Angeles, San Francisco, Seoul–Incheon, Vancouver | {{cn|date=May 2024}}

| EVA Air Cargo | Anchorage, Dallas/Fort Worth, Taipei–Taoyuan | {{cn|date=May 2024}}

| FedEx Express | Anchorage, Dallas/Fort Worth, Fort Worth/Alliance, Indianapolis, Los Angeles, Memphis, Oakland, Ontario, Portland (OR) | {{cn|date=May 2024}}

| FedEx Feeder | Bellingham, Burlington/Mount Vernon, Friday Harbor, Orcas Island, Port Angeles | {{cn|date=May 2024}}

| Kalitta Air | Los Angeles, Vancouver | {{cn|date=May 2024}}

| Korean Air Cargo | Chicago–O'Hare,{{cn|reason=Unable to find outbound flights to ORD, only inbound from|date=May 2024}} Los Angeles,{{cn|date=May 2024}} Seoul–Incheon | {{cite web |title=Flight Operation Status |url=https://cargo.koreanair.com/en/flight-operation-status |website=Korean Air Cargo |access-date=May 14, 2024 |archive-date=March 7, 2023 |archive-url=https://web.archive.org/web/20230307201901/https://cargo.koreanair.com/en/flight-operation-status |url-status=live }}

| Lufthansa Cargo | Frankfurt | {{cite web |title=Station Details: Seattle-Tacoma International (SEA) |url=https://www.lufthansa-cargo.com/de/network/maps/stations/details/SEA |publisher=Lufthansa Cargo |accessdate=May 14, 2024}}

| {{nowrap|Singapore Airlines Cargo}} | Anchorage,{{cn|date=May 2024}} Chicago–O'Hare, Dallas/Fort Worth,{{cn|date=May 2024}} Singapore | {{cite web |title=Flight Schedule |url=https://www.siacargo.com/e-services/flightschedule_public/ |website=Singapore Airlines Cargo |access-date=May 14, 2024 |archive-date=May 14, 2024 |archive-url=https://web.archive.org/web/20240514185713/https://www.siacargo.com/e-services/flightschedule_public/ |url-status=live }}

}}

{{Airport-Statistics|iata=SEA}}

• November 30, 1947: Alaska Airlines Flight 9, a Douglas C-54A en route to Seattle from Anchorage, Alaska, caught fire after overshooting the runway upon landing in heavy fog and damp conditions following failed attempts at nearby Boeing Field and Paine Field in Everett. Shortly before 2:30 p.m. on Sunday, the plane touched down {{convert|2748|ft|abbr=on}} beyond the approach area to runway 20 and sped onto a nearby road, colliding with a car and bursting into flames. Nine fatalities resulted from the accident, including a blind woman riding in the automobile.{{Cite news |date=December 1, 1947 |title=2 killed, 24 hurt, 2 missing in Seattle air liner crash |page=1 |work=Spokesman-Review |agency=Associated Press |location=(Spokane, Washington) |url=https://news.google.com/newspapers?id=0HxWAAAAIBAJ&sjid=lOUDAAAAIBAJ&pg=6317%2C150023 |archive-date=June 25, 2021 |access-date=June 25, 2021 |archive-url=https://web.archive.org/web/20210625052328/https://news.google.com/newspapers?id=0HxWAAAAIBAJ&sjid=lOUDAAAAIBAJ&pg=6317,150023 |url-status=live }}{{Cite news |date=December 2, 1947 |title=Alaska air line is put on spot |page=2 |work=Spokesman-Review |agency=Associated Press |location=(Spokane, Washington) |url=https://news.google.com/newspapers?id=0XxWAAAAIBAJ&sjid=lOUDAAAAIBAJ&pg=6746%2C241907 |archive-date=June 25, 2021 |access-date=June 25, 2021 |archive-url=https://web.archive.org/web/20210625052327/https://news.google.com/newspapers?id=0XxWAAAAIBAJ&sjid=lOUDAAAAIBAJ&pg=6746,241907 |url-status=live }}{{cite web |title=The Stories Behind the Stones |url=http://www.cemeteryguide.com/gotw-rebamonk.html |url-status=live |archive-url=https://web.archive.org/web/20120322024324/http://www.cemeteryguide.com/gotw-rebamonk.html |archive-date=March 22, 2012 |access-date=July 3, 2012 |website=Grave Spotlight}}
• April 2, 1956: Northwest Orient Airlines Flight 2, a Boeing 377 Stratocruiser headed to Portland International Airport in Portland, Oregon and points east, experienced reduced power and extreme buffeting shortly after takeoff from runway 20 due to an improper setting of the airplane's cowl flaps by the flight engineer. Plans were initially made to land at McChord Air Force Base, but the pilot was forced to make a water landing in Puget Sound east of Maury Island. The plane sank within 15 minutes; five of the 38 on board died.{{Cite news |date=April 2, 1956 |title=Plane carrying 37 crashes into Puget Sound; 4 dead |page=1 |work=Spokane Daily Chronicle |agency=Associated Press |location=(Washington) |url=https://news.google.com/newspapers?id=a_tXAAAAIBAJ&sjid=xvYDAAAAIBAJ&pg=1696%2C15160 |archive-date=June 25, 2021 |access-date=June 25, 2021 |archive-url=https://web.archive.org/web/20210625052327/https://news.google.com/newspapers?id=a_tXAAAAIBAJ&sjid=xvYDAAAAIBAJ&pg=1696,15160 |url-status=live }}{{Cite news |date=April 3, 1956 |title=Thirty-three safe as plane crashes in Puget Sound |page=1 |work=Lewiston Morning Tribune |agency=Associated Press |location=(Idaho) |url=https://news.google.com/newspapers?id=XcheAAAAIBAJ&sjid=TTIMAAAAIBAJ&pg=1505%2C3676400 |archive-date=June 25, 2021 |access-date=June 25, 2021 |archive-url=https://web.archive.org/web/20210625052327/https://news.google.com/newspapers?id=XcheAAAAIBAJ&sjid=TTIMAAAAIBAJ&pg=1505,3676400 |url-status=live }}{{Cite news |last=Black |first=Bruce R. |date=March 29, 2006 |title=Plane Crashed Near Des Moines Fifty Years Ago |work=Ballard News-Tribune |url=http://www.ballardnewstribune.com/2006/03/29/news/plane-crashed-near-des-moines-fifty-years-ago |url-status=live |access-date=July 3, 2012 |archive-url=https://web.archive.org/web/20130511212939/http://www.ballardnewstribune.com/2006/03/29/news/plane-crashed-near-des-moines-fifty-years-ago |archive-date=May 11, 2013}}
• November 24, 1971: Northwest Airlines Flight 305, a Boeing 727 flying to SEA Airport from Portland International Airport, was hijacked by a man calling himself "Dan Cooper," later misidentified by the press as "D. B. Cooper". Cooper released the passengers and attendants after landing in exchange for $200,000 and four parachutes, ordered the plane back into the air and jumped out over Southwest Washington with the money.{{Cite magazine |date=December 6, 1971 |title=CRIME: The Bandit Who Went Out into the Cold |magazine=Time Magazine |url=http://www.time.com/time/magazine/article/0,9171,877495,00.html |url-status=dead |access-date=July 3, 2012 |archive-url=https://web.archive.org/web/20120704223804/http://www.time.com/time/magazine/article/0,9171,877495,00.html |archive-date=July 4, 2012}} To this day, neither Cooper nor most of the $200,000 have been found.
• December 26, 1974: Harbor Airlines Flight 308, a Britten Norman Islander bound for Oak Harbor crashed 0.6 miles (1 km) north of SEA Airport in snowy weather conditions into Riverton. Four of the six occupants on board (3 passengers, 1 crew) were killed. Unknown matter in the pitot tubes caused improper readings of the airspeed indicator.{{ASN accident|id = 19741226-1|title =N66HA|access-date = April 11, 2019}}
• January 20, 1983: Northwest Airlines Flight 608, a Boeing 727 flying from SEA Airport to Portland, was hijacked. The man told a flight attendant that he had a bomb and demanded to be taken to Afghanistan. Federal agents stormed the plane after it landed in Portland for refueling. The hijacker was killed and the box he carried revealed no explosives.{{ASN accident|id=19830120-0|type=Hijacking}}
• April 15, 1988: Horizon Air Flight 2658, a twin-engine de Havilland Canada Dash-8 departing for Spokane International Airport, experienced a power loss in the number two engine shortly after takeoff. While the crew lowered the gear for landing as they returned to the airport, a massive fire broke out in the right engine nacelle, resulting in a loss of braking and directional control. After touchdown, the aircraft veered off the runway and crossed the ramp, colliding with two jetways before coming to a stop against a third. The aircraft was destroyed by fire on impact. Four of the 37 passengers were seriously injured, but there were no fatalities.{{Cite news |date=April 16, 1988 |title=18 Injured in Seattle Plane Crash |work=The New York Times |agency=Associated Press |url=https://www.nytimes.com/1988/04/16/us/18-injured-in-seattle-plane-crash.html |url-status=live |access-date=March 2, 2012 |archive-url=https://web.archive.org/web/20121108131325/http://www.nytimes.com/1988/04/16/us/18-injured-in-seattle-plane-crash.html |archive-date=November 8, 2012}}{{cite web |date=March 6, 1989 |title=Aircraft Accident Report—Horizon Air, Inc., deHavilland DHC-8, Seattle–Tacoma International Airport, Seattle, Washington, April 15, 1988 |url=http://www.airdisaster.com/reports/ntsb/AAR89-02.pdf |archive-url=https://web.archive.org/web/20111018161816/http://www.airdisaster.com/reports/ntsb/AAR89-02.pdf |archive-date=October 18, 2011 |access-date=March 2, 2012 |url-status=usurped |website=National Transportation Safety Board}}
• August 10, 2018: An empty Horizon Air Bombardier Q400 was stolen by a staff member and ultimately crashed on Ketron Island. Two US Air Force planes tried to force the plane to land.{{Cite news |date=August 10, 2018 |title=Turboprop stolen from Sea-Tac has crashed on Ketron Island in Pierce County |work=The News Tribune |url=https://www.thenewstribune.com/news/local/article216505205.html#storylink=latest_side |url-status=live |access-date=August 10, 2018 |archive-url=https://web.archive.org/web/20180811100133/https://www.thenewstribune.com/news/local/article216505205.html#storylink=latest_side |archive-date=August 11, 2018}}
• August 24, 2024: An apparent cyberattack caused airport officials to shut down a number of computer systems that handle the airport's website, ticketing/check-in kiosks, baggage handling system, and arrival/departure boards, leading to significant delays. Some airline and airport staff had to resort to writing out boarding passes by hand and manually sorting baggage.[https://washingtonstatestandard.com/2024/08/27/seatac-airport-outage-is-ongoing-heres-what-travelers-should-know/ Sea-Tac airport computer outage is ongoing. Here’s what travelers should know.], Washington State Standard, Aug. 27, 2024 The outages were mostly resolved with the website coming back online on November 22.{{cite web |url=https://www.portseattle.org/blog/port-website-back-online |title=Port Website is Back Online |publisher=Port of Seattle |date=2024-11-22 |archive-url=https://web.archive.org/web/20241123020343/https://www.portseattle.org/blog/port-website-back-online |archive-date=2024-11-23 |access-date=2024-11-25 }}
• February 5, 2025: A parked Boeing 737 operated by Delta Air Lines was struck by a taxiing Japan Airlines–operated Boeing 787 Dreamliner.{{Cite web |last=Flojo |first=Charmin |date=2025-02-05 |title=Japan Airlines plane clips tail of Delta plane at Sea-Tac Airport |url=https://www.fox13seattle.com/news/sea-tac-plane-hit-by-plane |access-date=2025-02-17 |website=FOX 13 Seattle |language=en-US}} Japan Airlines Flight 67 had landed at SEA and was taxiing before its right wing collided with the tail of another aircraft. The other aircraft, operating as Delta Air Lines Flight 1921, was waiting for deicing before takeoff to Puerto Vallarta, Mexico. Some flights were paused after the incident,{{Cite news |last=Levenson |first=Michael |date=2025-02-05 |title=Japan Airlines Plane Clips Delta Plane at Seattle-Tacoma Airport |url=https://www.nytimes.com/2025/02/05/us/delta-japan-airlines-collision-seattle-airport.html |access-date=2025-02-17 |work=The New York Times |language=en-US |issn=0362-4331 |archive-date=February 17, 2025 |archive-url=https://web.archive.org/web/20250217211346/https://www.nytimes.com/2025/02/05/us/delta-japan-airlines-collision-seattle-airport.html |url-status=live }} but no injuries were reported and the airport stated that there was a "minimal impact to airport operations."{{Cite web |date=2025-02-06 |title=Japan Airlines plane hits tail of Delta aircraft at SEA Airport |url=https://www.kiro7.com/news/local/japan-airlines-hits-tail-delta-aircraft-sea-airport/PTDBS6F2CNAXDPUDMGHCS45W3Y/ |access-date=2025-02-17 |website=KIRO 7 News Seattle |language=en |archive-date=February 8, 2025 |archive-url=https://web.archive.org/web/20250208125524/https://www.kiro7.com/news/local/japan-airlines-hits-tail-delta-aircraft-sea-airport/PTDBS6F2CNAXDPUDMGHCS45W3Y/ |url-status=live }}{{Cite web |date=2025-02-05 |title=No injuries after planes collide at SEA Airport on taxi line |url=https://www.king5.com/article/travel/no-injuries-planes-collide-sea-airport-taxi-line-ground-stop/281-ff4a5562-b3bb-498a-bf83-28c8105d9792 |access-date=2025-02-17 |website=king5.com |language=en-US}}

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{{Commons category|Seattle-Tacoma International Airport}}

{{wikivoyage|Seattle-Tacoma International Airport}}

• {{Official website}}
• [http://www.wsdot.wa.gov/aviation/AllStateAirports/Seattle_SeattleTacomaIntl.htm Seattle–Tacoma International Airport] at WSDOT Aviation
• [https://web.archive.org/web/20050204105203/http://www.historylink.org/results.cfm?keyword=st03 HistoryLink.org Online Encyclopedia of Washington State History] – Detailed articles on the history of the airport
• {{FAA-diagram|00582}}
• {{FAA-procedures|SEA}}
• {{US-airport|SEA}}

{{Airports in Washington}}

{{SeaTac, Washington}}

{{Major US Airports}}

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{{DEFAULTSORT:Seattle-Tacoma International Airport}}

Category:Airports in King County, Washington

Category:Seattle metropolitan area

Category:Economy of Seattle

Category:Economy of Tacoma, Washington

Category:Art Deco airports

Category:Airports established in 1944

Category:1944 establishments in Washington (state)

Airport

Category:Port of Seattle