Blue Line (Bangkok)

The MRT Blue Line begins from the upper platform of Tha Phra station. It runs on an elevated viaduct northward along Charan Sanit Wong Road to Bang O station before crossing the Chao Phraya River, entering Bang Pho station and Tao Poon station in Bang Sue District. The line then dives underground to reach Bang Sue. It follows the Kamphaeng Phet, Phahon Yothin and Lat Phrao Roads, then turns south following Ratchadaphisek Road to Queen Sirikit National Convention Centre station. It then turns west following Rama IV Road. It passes Hua Lamphong station in Pathum Wan District, through Chinatown, then under the Chao Phraya River before ascending onto an elevated viaduct to the lower platform of Tha Phra station. The line continues west along Phet Kasem Road to Lak Song station in Bang Khae, situated near Kanchanaphisek Road or Western Outer Ring road. It forms a quasi circle loop around Bangkok.

File:Tourniquet-Bangkok-metro 2010.jpg

File:Platform 1 of Phetchaburi MRT Station.jpg]]

File:Kamphaeng Phet Station - Exit level.jpg]]

File:MRT Wat Mangkorn vending machines.jpg.]]

Officially named Chaloem Ratchamongkhon (Thai สายเฉลิมรัชมงคล) – "Celebration of Royal Auspice" – or informally but commonly called as the "MRT Blue Line", this was the first metro line under the newly formed government agency, the Mass Rapid Transit Authority of Thailand (MRTA). Most civil infrastructure was provided by this government agency and handed over to a private sector on a 25-year concessionaire agreement. The winning bidder was Bangkok Expressway and Metro (BEM). Under this agreement, BEM provides maintenance and engineering equipment, including electrical trains, signalling systems, SCADA, communication, platform screen doors and fully operate the system from Hua Lamphong to Bang Sue.{{cite web|url=https://bem.listedcompany.com/misc/presentation/20190311-bem-presentation-march-2019-02.pdf|title=BEM Investor presentation}}{{cite web|url=https://www.mrta.co.th/(X(1)S(jl1ssviuj4rio3u4c1cwmxpy))/en/projectelectrictrain/bangkok-and-vicinities/chaleamline/?AspxAutoDetectCookieSupport=1|title=M.R.T. Chaloem Ratchamongkhon Line|website=MRTA Website|language=en|access-date=2020-04-24}} BEM has subcontracted maintenance of the system for 10 years to Siemens and seven-year maintenance contracts to two local maintenance services.{{cite web|url=https://mrta.co.th/en/MRTAproject/chaleamLine.php|title=Mass Rapid Transit Authority of Thailand|website=mrta.co.th|language=en|access-date=2017-04-14}}

In 1996, the Overseas Economic Cooperation Fund (OECF), later known as the Japan Bank for International Cooperation (JBIC), granted the loans for the project with an official development assistance (ODA) scheme. Construction of the line began on 19 November of that year, when Crown Prince His Royal Highness Crown Prince Maha Vajiralongkorn (later King Vajiralongkorn) came to lay the foundation stone for the construction of the MRT project, which is Thailand's first subway project, with the aim of relieving Bangkok's traffic problems. The first contract was awarded to a joint venture between CH. Karnchang Public Company Limited, Bilfinger-Berger, Kumagai Gumi, and Tokyu Construction Co. for the southern section, while one of the remaining contractors, the northern section, was awarded to ION Joint Venture, which comprises Italian Thai Development, Obayashi Corporation, and Nishimatsu Construction, and the depot was awarded to Siam Nippon Metro Consortium, composed of Hazama Corporation, Maeda Corporation, Mitsui & Co., Kajima, T.S.B. Trading, and Siam Syntech Construction Public Co., Ltd. Tunneling works began on 5 February 1999.{{Cite web |title=รถไฟใต้ดินจำลองของจริง |date=3 January 2021 |url=https://readthecloud.co/mrt-groundbreaking-ceremony/ |access-date=13 July 2024}}{{cite book |author=Messe München |author-link=Messe München |url=https://books.google.com/books?id=GmrGZOjeSwIC&pg=PA73 |title=Tunnel Construction |date=1 January 1998 |publisher=CRC Press |isbn=978-90-5410-951-8 |pages=73–81}}{{Cite web |title=Thailand starts digging tunnels for 1st Bangkok subway. - Free Online Library |url=https://www.thefreelibrary.com/Thailand+starts+digging+tunnels+for+1st+Bangkok+subway.-a053924034 |access-date=2024-05-18 |website=www.thefreelibrary.com}}

During construction, the consultancy was led by the "Berger-CSC 1 Consortium," comprising the following consulting firms: Louis Berger and many more, as well as a joint venture of Mott Macdonald and De Leuw Cather.{{Cite web |title=M.R.T. Chaloem Ratchamongkhon Line |url=http://ceat.or.th/index.php/component/content/article/m-r-t-chaloem-ratchamongkhon-line?catid=16&Itemid=227 |access-date=2024-12-20 |website=ceat.or.th}}{{Cite book |title=Rail Business Report |publisher=Railway Gazette International |year=1998}}

The project suffered multiple delays not only because of the 1997 economic crisis, but also due to challenging civil engineering works of constructing massive underground structures deep in the water-logged soil upon which the city is built. The MRT Blue Line opened for a limited public trial period of several weeks starting on 13 April 2004. On 3 July 2004, the line was officially opened at 19:19 local time by HM King Bhumibol and Queen Sirikit who were accompanied by other members of the royal family. Within 30 minutes of its opening, sightseers filled the system to its maximum capacity, but after the initial rush ridership settled down to around 180,000 riders daily—considerably lower than projections of over 400,000, despite fares being slashed in half from 12 to 38 baht to 10-15 baht per trip.Bangkok's First Underground Metro Opens International Railway Journal July 2004 page 32{{Cite news |date=2004-07-03 |title=Congested Bangkok opens subway |url=https://www.abc.net.au/news/2004-07-04/congested-bangkok-opens-subway/2003542 |access-date=2024-07-10 |work=ABC News |language=en-AU}} It was scheduled to be opened in 2003, in time for the same year's APEC summit, and later pushed back again to April and then August of the following year.{{Cite web |last= |last2= |first2= |date=14 January 2003 |title=Bangkok to launch subway system in 2004 |url=https://www.metro-magazine.com/10030350/bangkok-to-launch-subway-system-in-2004 |access-date=2024-07-10 |website=www.metro-magazine.com |language=en-US}} However, no problems were encountered during the test run; the official opening was brought forward.

During the early years, it was named the subway as an alternate name.

As part of the rapid transit master plan the original MRT Blue Line section was planned to be extended from Hua Lamphong to Lak Song, and from Bang Sue to Tha Phra, forming a circle open-loop route. The contract for the first part of extension to Tao Poon was signed on 26 August 2009{{cite web|url=https://www.thairath.co.th/content/28906|title=ลงนามสัญญาที่1 รถไฟสีม่วง ช.การช่างได้เฮ|date=2009-08-26|website=thairath.co.th|language=th|access-date=2020-04-24}} as part of MRT Purple Line contract as it provided interchange to the MRT Purple Line. The {{convert|1.2|km|abbr=on}} Bang Sue to Tao Poon extension opened on 11 August 2017.{{cite news|url=https://www.bangkokpost.com/thailand/general/1285890/purple-line-to-connect-with-mrt-on-aug-11|title=Purple Line to connect with MRT on Aug 11|newspaper=Bangkok Post|date=12 July 2017 |access-date=2020-04-24}} This added the first elevated station, Tao Poon, to the Blue line.{{cite web|url=https://www.thairath.co.th/news/business/1034684|title=Blue Line Tao Poon extension opening date (Thai)|date=11 August 2017 }}{{cite web|url=https://www.bangkokbiznews.com/news/detail/768436|title=เปิดวิ่งเชื่อมต่อสถานีเตาปูน-บางซื่อ 12.00 วันนี้|website=bangkokbiznews.com/|date=11 August 2017 |language=en|access-date=2020-04-27}}

The major extension of the MRT Blue Line was the {{convert|27|km|4=1|abbr=on}} extension west to Lak Song and from Tao Poon to Tha Phra with 19 stations consisting of four underground and 15 elevated stations. Contracts for civil work were divided into five contracts. Successful bids were announced in late 2010.{{cite web|url=https://www.posttoday.com/economy/news/36930|title=ช.การช่างคว้าประมูลรถไฟฟ้าสีน้ำเงินหัวลำโพง-ท่าพระ|website=posttoday.com|date=July 2010 |language=en|access-date=2020-04-24}}{{cite web|url=https://www.thairath.co.th/content/86949|title=ยูนิค-ชิโนไทย ชนะประมูลสร้างรถไฟฟ้าสีน้ำเงิน 2 สัญญา|date=2010-06-02|website=thairath.co.th|language=th|access-date=2020-04-24}}{{cite web|url=https://www.thairath.co.th/content/106055|title=ช.เข้าวินวางรางสีน้ำเงิน รฟม.ยัน 5 สัญญาเซ็นได้ ต.ค.นี้|date=2010-08-25|website=thairath.co.th|language=th|access-date=2020-04-24}} On 17 February 2011, the five contracts were signed.{{cite web|url=https://www.mrta.co.th/(X(1)S(y2wbviwzeakkvpkly54s1yhi))/en/document_publications/document/?AspxAutoDetectCookieSupport=1|title=Published {{!}} การรถไฟฟ้าขนส่งมวลชนแห่งประเทศไทย|website=mrta.co.th|access-date=2020-04-24}}[https://www.railwaygazette.com/bangkok-to-complete-blue-line-loop/35788.article Bangkok to complete Blue Line loop] Railway Gazette International 19 March 2011

Construction commenced in mid-2011 for a scheduled 2016 opening but this was subsequently delayed to 2019–2020. In August, 2017, BEM awarded the automatic fare collection ticket for the extension to Thales which to install its TransCity system.{{cite news|url=http://www.railjournal.com/index.php/metros/thales-wins-bangkok-metro-fare-collection-contract.html?channel=525|title=Thales wins Bangkok metro fare collection contract|date=23 August 2017|newspaper=International Railway Journal}} The contract also includes ongoing training and future support. In September 2017, BEM announced that Siemens and ST Electronics Thailand were awarded the contract (Contract 5) to supply, install and maintain the E&S systems, install station platform screen doors and fit out the depot. Siemens also won the contract to supply 35 sets of rolling stock.{{cite news|url=http://www.railjournal.com/index.php/metros/siemens-consortium-wins-bangkok-blue-line-extension-contract.html?channel=525|title=Siemens consortium wins Bangkok Blue Line extension contract|date=19 September 2017|newspaper=International Railway Journal}}

In 2017, the cabinet approved the amendment of the Blue line concession{{cite web|url=https://mgronline.com/business/detail/9600000031726|website=mgronline.com|access-date=2020-04-24|title=ปิดดีลเดินรถสีน้ำเงิน ครม.ผ่านฉลุย เร่งเซ็นสัญญาจ้าง Bem ทยอยเปิดเดินรถปลายปี 62 |date=28 March 2017 }} with BEM, and the new agreement was signed on 31 March 2017.{{cite web|url=https://bem.listedcompany.com/misc/mdna/20180228-bem-mdna-fy2017-en.pdf|title=BEM significant event in 2017}} Under the new agreement, BEM will operate the new extensions from Hua Lamphong to Lak Song and Bang Sue to Tha Phra. The concession period was extended from 2029 to 2050.{{Cn|date=August 2023}}

File:Wat Mangkon MRT Station 02.jpg|Wat Mangkon station under construction. The station opened on 29 July 2019.

File:Bang Wa MRT Station (under construction), June 2016.jpg|Bang Wa station under construction. The station opened on 29 July 2019.

File:MRT Blue Line extension under construction 20-Dec-2013.jpg|Under construction viaduct outside of Lak Song station in 2013.

File:Bangkok Noi Streets Ahoerstemeier 12.jpg|Construction of Fai Chai station and Fai Chai junction underpass in 2016.

The extension was opened in stages. The Hua Lamphong - Lak Song extension was opened for trial service on 29 July with full commercial services commencing 29 September 2019.

The Tao Poon - Tha Phra extension opened for limited trial services from 29 November 2019 with full commercial services commencing on 30 March 2020.

Since 2011, there were requests from residents to extend the line farther from Lak Song west to the Phutthamonthon area. The MRTA indicated a willingness to undertake this extension. In July 2014, the MRTA submitted a request for 84 million baht to complete a route survey for a {{Cvt|7.8|km}}, 4 station extension from Lak Song to Phutthamonthon Sai 4.{{cite web |date=15 July 2014 |script-title=th:ลุ้นคลังไฟเขียวงบรถไฟ-รฟม |trans-title=Win No Green Light Railway Company - MRTA |url=http://www.thanonline.com/index.php?option=com_content&view=article&id=238847:2014-07-15-06-17-28&catid=129:2009-02-08-11-47-38&Itemid=479#.U8jZIPmSwnX |website=Than Online |language=th}} In late March 2017, the Transport Ministry stated that this {{Convert|7.8|km|abbr=on}} extension would be submitted to Cabinet for approval in April 2017 with construction expected to commence in the 4th quarter of 2017.{{cite news |date=26 March 2017 |title=Blue Line extension, freeway pends Cabinet approval |url=http://www.bangkokpost.com/news/transport/1221270/blue-line-extension-freeway-pends-cabinet-approval |access-date=28 March 2017 |newspaper=The Bangkok Post |location=Bangkok |last1=Mahitthirook |first1=Amornrat }} However, the tender was subsequently delayed until late 2019 due to other projects. In late 2019, the project was put on hold due to government budget constraints.{{cite web |title=ชะลอทำรถไฟฟ้า3สายหวั่นผู้โดยสารน้อย/ไม่คุ้มทุน |url=https://www.ryt9.com/s/nnd/3012056 |access-date=2020-04-24 |website=ryt9.com |language=th}} In August 2021, the MRTA confirmed that the extension was not a priority especially given delays with the tenders for the MRT Orange and MRT Purple line extensions.{{cite news |date=19 August 2021 |title=รฟม.ขึงไทม์ไลน์ ต.ค.ประมูล "สายสีส้ม-สีม่วงใต้" ยึด กม.จัดซื้อฯ ยันเกณฑ์เทคนิคและราคาเหมาะสม |url=https://mgronline.com/business/detail/9640000081947 |newspaper=Manager}}

{{further|List of rapid transit stations in Bangkok}}

The MRT Blue Line has two depots. The main maintenance depot, Huai Khwang Depot, is located on Rama IX Road within the premises of the Mass Rapid Transit Authority of Thailand. Construction began in 2005 and was completed the following year. {{Cite web |title=ศูนย์ซ่อมบำรุงรถไฟฟ้าใต้ดินสายเฉลิมรัชมงคล |url=https://www.ch-karnchang.co.th/th/construction-project/mass-rapid-transit-system/15/%E0%B8%A8%E0%B8%B9%E0%B8%99%E0%B8%A2%E0%B9%8C%E0%B8%8B%E0%B9%88%E0%B8%AD%E0%B8%A1%E0%B8%9A%E0%B8%B3%E0%B8%A3%E0%B8%B8%E0%B8%87%E0%B8%A3%E0%B8%96%E0%B9%84%E0%B8%9F%E0%B8%9F%E0%B9%89%E0%B8%B2%E0%B9%83%E0%B8%95%E0%B9%89%E0%B8%94%E0%B8%B4%E0%B8%99%E0%B8%AA%E0%B8%B2%E0%B8%A2%E0%B9%80%E0%B8%89%E0%B8%A5%E0%B8%B4%E0%B8%A1%E0%B8%A3%E0%B8%B1%E0%B8%8A%E0%B8%A1%E0%B8%87%E0%B8%84%E0%B8%A5 |access-date=2025-04-29 |website=www.ch-karnchang.co.th |language=th}} The site is also shared with the MRT Orange Line project.

The secondary depot, Phetkasem Depot, is located on Kanlapaphruek Road. It was built as part of the Blue Line extension projects and was completed in 2019.

There are fourteen Park & Ride facilities located at eleven stations, consisting of three Park & Ride buildings and eleven parking lots, with a total capacity of 5,144 vehicles.{{Cite web |title=ที่จอดรถสายเฉลิมรัชมงคล (สายสีน้ำเงิน) |url=https://www.mrta.co.th/th/general-data |access-date=2025-04-29 |website=www.mrta.co.th |language=th}}

There are 38 stations on the network, 22 of which are underground and 16 of which are elevated.File:TLCC Station - Blue Line platform level (1).jpg.]]

The stations are generally about 150 meters in length, except for the Thailand Cultural Centre Station, which extends to 358 meters due to its role as an interchange station for the MRT Orange Line and as a junction for tracks leading to the Huai Khwang Depot. The stations are designed to accommodate a maximum of six cars per train. All stations are equipped with both half-height and full-height platform screen doors. The underground stations and tracks are designed to be durable and resilient to land subsidence and to withstand vibrations in the event of an earthquake, without causing damage to the structure. The entrances to the stations are designed to be about one meter above ground level to accommodate potential flooding events in the future, based on the highest recorded flood levels in Bangkok. Elevated stations are designed to avoid underground and above-ground utilities and to preserve the road surface as much as possible. In general, station pillars are located in the median of roads, except for stations that need to span underground tunnels, where the station pillars are placed on the sidewalks instead.

The MRT Blue line is served by 54 three-car trains of which, 19 are first generation Siemens Modular Metro sets and 35 sets are second generation. The trains are powered by 750 V DC via third rail system, are air-conditioned and capable of traveling at up to {{Cvt|80|km/h}}.{{cite web |title=BEM บริษัททางด่วนและรถไฟฟ้ากรุงเทพจำกัด (มหาชน) |url=https://metro.bemplc.co.th/MRT-System-Line?pid=3 |access-date=2020-04-26 |website=metro.bemplc.co.th |language=th}}

Nineteen three-car Siemens Modular Metro were ordered for the initial part of the line. The trains entered service on 3 July 2004.{{cite web |title=Bangkok Metro |url=https://www.railway-technology.com/projects/bangkok-metro/ |access-date=2020-04-26 |website=Railway Technology |language=en-GB}} In 2017, BEM starts removing some seats from the train to increase interior space to cope with rising number of passengers. In 2019, the BEM stated that it is interested in refurbishing the first generation trains. Including the CCTV cameras, and new dynamic route map replacing the traditional ones.{{cite web |title=บุกโรงงานซีเมนส์...ผลิตรถไฟฟ้า MRT-BEM ดีไซน์เพิ่มระบบเซฟตี้รองรับผู้โดยสารทุกกลุ่ม |trans-title= |url=https://mgronline.com/business/detail/9620000110394 |access-date=2020-04-26 |website=mgronline.com |date= 18 November 2019|lang=th}}

In 2000, Alstom won a contract to supply 21x3 car Metropolis train sets, and this design would have been similar to C751A used for Singapore's North East MRT line if it had been built. The trains were provided by a consortium called Nippon-Euro Subway Consortium, which also includes Mitsubishi Electric.{{Cite web |title=ALSTOM chosen for the Blue Line of the Bangkok metro |url=https://www.alstom.com/press-releases-news/2000/9/ALSTOM-chosen-for-the-Blue-Line-of-the-Bangkok-metro-20000905 |access-date=2024-05-17 |website=Alstom |language=en}} Mitsubishi Corporation, another consortium member, had also planned to undertake it.{{Cite web |title=Rail News - Alstom-led consortium lands Bangkok concession. For Railroad Career Professionals |url=https://www.progressiverailroading.com/passenger_rail/news/Alstom-led-consortium-lands-Bangkok-concession--11085 |access-date=2024-07-10 |website=Progressive Railroading |language=en}} However, the negotiations with the French firm have failed. The bidding for rolling stock was conducted again, and bidders include Bombardier Transportation (later acquired by Alstom in 2021) and Siemens, both from Canada and Germany.{{Cite news |date=1 January 2002 |title=Siemens wins $385-M contract for Bangkok subway system |work=AFP}} On 3 January 2002, Siemens won the contract for a cost of $385 million.{{Cite web |last=International2002-02-01T11:00:00 |first=Railway Gazette |title=Siemens scoops Bangkok order |url=https://www.railwaygazette.com/news/siemens-scoops-bangkok-order/25848.article |access-date=2024-05-17 |website=Railway Gazette International |language=en}}

In late 2019, IBL trains were refurbished with the installation of CCTV, LED lights, and an LCD dynamic route map.

* Car 1016 and 1028 were swapped after the train collision in 2005.

File:MRT-BLUELINE-IBL.jpg|The first generation train, Siemens Modular Metro EMU-IBL (Initial Blue Line stock)

File:MRT Blue Line Bangpai Station (9).jpg|EMU-IBL approaching Bang Phai station with Tha Phra station in the background.

File:MRT Blue Line Bangpai Station (11).jpg|Another picture of EMU-IBL approaching Bang Phai station.

File:MRT blue Line Train 14 20180917.jpg|EMU-IBL approaching Tao Poon station with the unfinished Krung Thep Aphiwat Central Terminal in the background in 2018.

File:Inside the train of MRT blue line.jpg|The interior of EMU-IBL before the refurbishment.

In 2017, BEM ordered 35 three-car as part of the line extension program.{{cite news |title=BEM to buy 35 more Blue Line trains |url=https://www.bangkokpost.com/thailand/general/1324479/bem-to-buy-35-more-blue-line-trains |access-date=2020-04-26 |newspaper=Bangkok Post|date=15 September 2017 |last1=Chudasri |first1=Darana }}{{cite web |date=2017-09-19 |title=Siemens wins contract for Bangkok Blue line extension |url=https://www.railwaypro.com/wp/siemens-wins-contract-bangkok-blue-line-extension/ |access-date=2020-04-26 |website=Railway PRO |language=en-US}} Under the contract, Siemens were to supply 35 trains and provide maintenance for ten years with a price tag of 20 billion baht. The fleet was built at the Siemens plant in Vienna and tested in Germany. The first train arrived in 2019 with all trains delivered by early 2020.{{cite web |title=MRTA – BEM Announce that the First New Train for the MRT Blue Line Extension Has Arrived |url=https://www.ryt9.com/en/prg/226062 |access-date=2020-04-26 |website=ryt9.com |language=th}}

File:MRT-BLUELINE-BLE.jpg|The second generation train,Siemens EMU-BLE (Blue Line Extension stock)

File:MRT Fai Chai – Platform – train leaving 1.jpg|EMU-BLE departing Fai Chai station.

File:MRT Blue Line Bangpai Station (6).jpg|EMU-BLE approaching Bang Phai station with Tha Phra station in the background.

File:MRT Blue line EMU-BLE Interior.jpg|Interior of the EMU-BLE

File:Dynamic Route Map in EMU-BLE.jpg|Dynamic Route Map on the EMU-BLE.

On 18 July 2024, Mr. Phongsarit Tantisuvanitchkul, executive chairman of BEM revealed that the company will order an additional 21 train sets, each comprising three cars, for the MRT Blue line to meliorate congestion during peak hour.{{Cite web |last=Siripanjana |first=Maneerat |title=วันนี้ที่รอคอย! ลงนามร่วมทุน "สายสีส้ม" เร่งเปิดเดินรถปลายปี 70 ของขวัญปีใหม่ประชาชน |url=https://www.dailynews.co.th/news/3658119/ |access-date=2024-07-18 |website=เดลินิวส์ |language=th}} The turnkey contract was announced on 18 December 2024. A consortium consisting of Siemens and Bozankaya won a contract from Ch. Karnchang. The contract includes the supply of 21 Siemens three-car trains, with the design same as the EMU-BLE fleet that is currently used on the project. These trains will be manufactured at the Bozankaya Factory in Ankara, Turkey. Siemens and ST Electronics will supply the bogies, traction, braking, and auxiliary systems, and will be responsible for project management, development, construction, and commissioning. Siemens will also provide service and maintenance for 15 years, from 2024 to 2039.{{Cite web|title=Siemens Mobility and Consortium Partners Secure Important Rail Contracts in Thailand to Transform Public Transportation |url=https://press.siemens.com/global/en/pressrelease/siemens-mobility-and-consortium-partners-secure-important-rail-contracts-thailand |access-date=2024-12-18 |website=Siemens Mobility |language=en}}

Siemens Trainguard LZB700M signaling system, a Fixed Block system, has been implemented on the MRT Blue Line. It utilizes a computer-based system to automatically control train operations for maximum efficiency, speed, and safety. The system is divided into three subsystems:

• Automatic Train Operation (ATO) – Controls various functions of the train, such as propulsion, speed regulation, braking, stopping the train, and reporting the status of various components to the control center.
• Automatic Train Protection (ATP) – Ensures that the train does not exceed the set speed limit and regulates the train’s speed relative to the distance from the train ahead. In the event of abnormal situations, ATP will automatically apply the brakes. It also prevents the train from departing a station if the train doors or platform screen doors are not properly closed. Unlike ATO, which can be manually overridden if it malfunctions, ATP continues to control train operations independently.
• Automatic Train Supervision (ATS) – Oversees the entire train network to ensure that operations adhere to the timetable. It monitors and displays the speed and location of all trains within the system and prepares control measures in case of disruptions. {{Cite web |title=Data Sheet Blue Line Extension Bangkok English |url=https://assets.new.siemens.com/siemens/assets/api/uuid:3a0036d5-ee40-40b3-b62e-38d10a0bac82/datasheet-bangkokbluelineextension-english.pdf}}

The MRT Blue Line operates from 05:30 to 24:00 on weekdays and from 06:00 to 24:00 on weekends and public holidays. During the weekday morning rush hour, there are two service patterns:

• Full Line operation from Tha Phra to Lak Song.
• Short-run train from Bang Pho to Lak Song.

Additionally, some trains may terminate at Chatuchak Park or Bang Wa stations during rush hour.

At opening in 2004, initial ridership was 180,000 per day—considerably lower than the projections of over 400,000. By 2016, the average daily ridership was 273,637.{{cite web |date=2017 |title=Financial Summary of the Consolidated Financial Statements of Bangkok Expressway and Metro Public Company Limited and its Subsidiaries |url=http://investor.bemplc.co.th/misc/ar/ar2016/20170310-bem-ar2016-enc01-en.pdf}} By September 2017, BEM stated that average daily ridership had increased to 360,000 after the opening of the extension to Tao Poon.{{cite news |date=15 September 2017 |title=BEM to buy 35 more Blue Line trains |newspaper=Bangkok Post |location=Bangkok |url=http://www.bangkokpost.com/news/transport/1324479/bem-to-buy-35-more-blue-line-trains |last1=Chudasri |first1=Darana }}

After the opening of the extension to Lak Song on 29 September 2019, average daily ridership increased to 400,000. The MRT Blue line was expected to grow to a daily ridership of 800,000 once the Lak Song and Tha Phra extensions opened. However, the impact of the COVID-19 pandemic by late 2020 had resulted in a dramatic reduction of ridership down to an average of 360,000 per weekday reverting to September 2017 levels.เช็กคืบหน้ารถไฟฟ้าทุกสี ต้นปี 64 เปิดประมูล สีม่วง "เตาปูน-ราษฎร์บูรณะ. Prachachat, 1 December 2020 By August 2021, during a COVID-19 3rd wave in Bangkok ridership plummeted to only 76,000 per weekday.{{cite web |title=BEM website. Monthly ridership. |url=https://investor.bemplc.co.th/en/ridership-report/ridership}} In 2023 an average of 376,000 passengers rode the blue line.{{cite web |title=Minisery of rail transport. |url=https://www.drt.go.th/library/statistics}}

From 25 January to 31 January 2025, Prime Minister Paetongtarn Shinawatra has implemented a policy of free public transportation in Bangkok for one week. This measure aims to address the worsening air pollution caused by surging dust levels across all districts of the capital.{{Cite news |last=Boyle |first=Gary |date=2025-01-25 |title=PM orders week of free public transport to combat PM2.5 |url=https://www.bangkokpost.com/learning/easy/2947262/pm-orders-week-of-free-public-transport-to-combat-pm2-5 |access-date=2025-01-25 |work=Bangkok Post |language=en}}

Fares for the MRT Blue Line are calculated based on the shortest travel distance between the origin and destination stations, regardless of the actual route taken. Passengers may stay within the system for up to 180 minutes; exceeding this limit will result in a penalty fare. Regular fares range from 17 to 45 baht, with a maximum fare of 51 baht when transferring to the Purple Line. Discounted fares are available for children under 14 years old and senior citizens, ranging from 9 to 23 baht (up to 36 baht with a transfer to the Purple Line), while student fares range from 14 to 41 baht (up to 48 baht with a transfer to the Purple Line).

Starting in 2024, passengers using a Credit/Debit card, Visa, or Mastercard will receive a 15 baht discount when transferring from the Blue Line to the Yellow Line, or a 14 baht discount when transferring from the Yellow Line to the Blue Line. Furthermore, senior citizens will receive an 8 baht discount when transferring from the Blue Line to the Yellow Line, and a 7 baht discount when transferring from the Yellow Line to the Blue Line. Students will receive a 15 baht discount when transferring from the Blue Line to the Yellow Line, and a 13 baht discount when transferring from the Yellow Line to the Blue Line.{{Cite web |title=อัตราค่าโดยสาร |url=https://www.mrta.co.th/th/fares |access-date=2025-04-29 |website=www.mrta.co.th |language=th}}

On 17 January 2005, just after 09:15, an empty train returning to the depot collided with a peak-hour train filled with passengers at the Thailand Cultural Centre station. Around 100-262 people, depending on the news source, were injured.{{cite web |date=2019-04-14 |title=3 นาทีคดีดัง : ชนสนั่น! วันโกลาหล รถไฟฟ้าใต้ดิน (คลิป) |url=https://www.thairath.co.th/scoop/1543451 |access-date=2020-04-27 |website=thairath.co.th |language=th}}{{cite web |date=17 January 2005 |title=เจ็บเป็นร้อย!!! รถไฟฟ้าใต้ดินชนกัน คนขับสาหัส |url=https://mgronline.com/crime/detail/9480000007248 |access-date=2020-04-27 |website=mgronline.com}}{{cite web |title=Article with photos of an event |url=https://www.bloggang.com/viewdiary.php?id=hematite&month=01-2006&date=21&group=1&gblog=8}} Most of whom sustained only minor injuries, and the entire Metro network was shut down for two weeks. On 31 January 2005, then prime minister Thaksin Shinawatra rode the metro to increase public confidence in the system.

After initial investigations, it was found that the empty train had run into problems shortly before the accident, grinding to a halt on a curve leading to the depot. The driver applied its brake and was waiting to be towed to the depot close to Thailand Cultural Centre station. A rescue train was attempting to connect to the stalled train when the driver was told to release the brake while coupling had not yet been successful. It was then that the empty train began to roll backwards at a speed of ten meters per second, before smashing into the other train, which was carrying passengers. Therefore, it was believed that the incident was caused by negligence due to insufficient training of operation staff.{{cite news |date=17 January 2005 |title=Thai subway shut for safety probe |work=BBC News |url=http://news.bbc.co.uk/2/hi/asia-pacific/4180109.stm |access-date=13 May 2010}} This accident also resulted in two damaged trains with heavily damaged areas limited to the two leading cars. The colliding speed was suspected to be about 60 km/h due to the appearance of damaged areas. However, one train, which was rebuilt from the repair of the minor-damaged cars, was already fitted for operation at the end of 2006 and the remaining one was still under heavy repair until mid of 2007; it was released into service in October 2007. The cost resulting from the accident might be a much higher figure than BEM quoted, and it was expected to be at least 400 million baht, which was totally insured by a local insurance company.

The line resumed full operations on 1 February 2005. Passenger numbers soon rose back to pre-crash levels, partly due to a temporary promotional fare scheme which allowed passengers to travel any distance on the MRT for only ten baht.

On March 28, a 7.7-magnitude earthquake in Myanmar struck Bangkok, leading to the temporary suspension of all train services to ensure readiness for resumption and to prepare for potential aftershocks. The line resumed normal service on the next day.{{Cite web |date=2025-03-28 |title=Train services suspended for safety after earthquake in Myanmar |url=https://www.nationthailand.com/news/general/40047989 |access-date=2025-04-02 |website=nationthailand |language=en-US}}

{{Wide image|MRT Blue Line Map 2024.svg|1600px}}

{{Rapid transit OSM map

| frame-lat = 13.7664

| frame-long = 100.495

| frame-width = 950

| frame-height = 350

| zoom = 12

| stations = y

| single_line = y

| text = Route of the Blue Line

| plain = no

| frame-align = left

}}

{{Wide image|2023versionofbangkokmassrapidtransitmap.png|700px}}

File:Wat Mangkon MRT Station 08.jpg|The ceiling at {{MRT Station Numbering|BL|29}} Wat Mangkon station.

File:MRT Blue Line Sam Yot Station (8).jpg|Exterior of Sam Yot MRT station.

File:MRT Blue Line Sam Yot Station (15).jpg|The interior design of Sam Yot MRT station.

File:Transfer hall at Sam Yot Station.jpg|The transfer hall at {{MRT Station Numbering|BL|30}} Sam Yot station is reserved for the {{rint|bangkok|Purple}} southern section (under construction)

File:MRT Blue Line Sanamchai Station (3).jpg|The interior design at Sanam Chai MRT station

File:Itsaraphap MRT Station 03.jpg|The design of {{MRT Station Numbering|BL|32}} Itsaraphap station

File:MRT Ta Phra station (View from Charansanitwong Rd.).jpg|Tha Phra MRT station from ground level.|alt=BL01  Tha Phra station from ground level.

File:Bangkok MRTA Metro Depot (2902961809).jpg|Phra Ram 9 Depot under construction in 2002.

File:MRT Blue Line Sanamchai Station (12).jpg|Underground museum at {{MRT Station Numbering|BL|31}} Sanam Chai station.

{{Div col|colwidth=20em}}

• Mass Rapid Transit Master Plan in Bangkok Metropolitan Region
• MRT (Bangkok)
• MRT Brown Line
• MRT Grey Line
• MRT Light Blue Line
• MRT Orange Line
• MRT Pink Line
• MRT Purple Line
• MRT Yellow Line
• BTS Skytrain
• BTS Sukhumvit Line
• BTS Silom Line
• AERA1 City
• SRT Light Red Line
• SRT Dark Red Line
• Bangkok BRT
• BMA Gold Line

{{Div col end}}

{{reflist}}

{{Commons category|MRT Blue Line}}

• {{Official website|https://www.mrta.co.th/en/mrt-chaloem-ratchamongkhon}}
• [https://web.archive.org/web/20130112000208/http://www.mrta-blueline.com/ "MRTA Blue Line extension website"] (archived)
• [https://www.bts.co.th/eng/routemap.html Airport Rail Link, BTS, MRT & BRT network map]

{{Bangkok Rapid Transit stations

|Blue=yes

}}

{{Public transport in Bangkok}}

{{Urban Rail Transit in ASEAN}}

Category:MRT (Bangkok) lines

Category:2004 establishments in Thailand

Category:Railway lines opened in 2004

Category:750 V DC railway electrification

Category:Standard-gauge railways in Thailand