Peter O'Mahony

O'Mahony was born in Cork, where he attended Presentation Brothers College. He went on to enter the Munster academy in 2008 and captained the Ireland under-20s in the 2009 Six Nations Under-20s Championship and 2009 IRB Junior World Championship.{{cite news|url=http://munsterrugby.ie/player?PlayGuid=PO196534|title=Munster Rugby Profile|work=Munster Rugby|access-date=3 April 2017}} O'Mahony won the 2009–10 All-Ireland Cup with Cork Constitution and was named player of the match in the final.{{cite news|url=http://www.independent.ie/sport/rugby/omahony-drives-defiant-con-home-2042072.html|title=O'Mahony drives defiant Con home|date=1 February 2010|work=Irish Independent}} He was also part of the Cork Constitution team that won the 2009–10 All-Ireland League alongside current Munster teammates Stephen Archer and Simon Zebo and former teammates Duncan Williams, Ian Nagle, Tom Gleeson and Brian Hayes.{{cite news|url=http://www.irishrugby.ie/news/19462.php#.WUJ4-GjyvIU|title=Division 1 Final Preview: Cork Constitution v St. Mary's College|date=7 May 2010|work=Irish Rugby|access-date=15 June 2017}}{{cite news|url=http://www.irishtimes.com/sport/cork-constitution-go-the-distance-1.663280|title=Cork Constitution go the distance|date=10 May 2010|work=Irish Times|access-date=15 June 2017}}{{cite news|url=https://www.rsvplive.ie/news/celebs/gallery/ireland-rugby-star-peter-omahony-23557918|title=Ireland rugby star Peter O'Mahony and wife Jessica welcome baby number three|date=24 February 2021|work=RSVP Live|access-date=27 February 2021}}

O'Mahony made his Munster debut against Ulster on 2 January 2010, coming on as a replacement for James Coughlan.{{cite news|url=https://munsterrugby.ie/report/mistakes-cost-munster/|title=Mistakes Cost Munster|date=3 January 2010|work=Munster Rugby|access-date=13 November 2011}} He captained Munster A to the final of the inaugural British and Irish Cup in the 2009–10 season.{{cite news|url=http://www.irishrugby.ie/news/19473.php#.WdxppviGPcs|title=Munster Miss Out on British & Irish Cup Title|date=16 May 2010|work=Irish Rugby}} O'Mahony was promoted to a full development contract with Munster for the 2010–11 season. He was an integral part of the team when the internationals were away for the 2010 November Tests, putting in a big performance in Munster's historic 15–6 victory against Australia, a game which was also O'Mahony's first start for Munster.{{cite news|url=https://www.munsterrugby.ie/report/class-of-2010-excel/|title=Class of 2010 Excel|date=17 November 2010|work=Munster Rugby|access-date=13 November 2011}}

O'Mahony captained Munster in their opening Pro12 match against Dragons in September 2011,{{cite news|url=https://munsterrugby.ie/preview/munster-have-to-hit-the-ground-running/|title=Munster Have To Hit The Ground Running|date=3 September 2011|work=Munster Rugby|access-date=3 September 2011}} and continued to captain Munster whilst their international contingent were away at the 2011 Rugby World Cup. He made his Heineken Cup debut for Munster against Northampton Saints on 12 November 2011,{{cite news|url=https://munsterrugby.ie/2011/11/11/academy-graduates-make-their-heineken-debut-2/|title=Academy Graduates Make Their Heineken Debut|date=11 November 2011|work=Munster Rugby|access-date=13 November 2011}} a game in which he won the Man-of-the-Match award.{{cite news|url=https://munsterrugby.ie/2011/11/14/a-day-of-firsts-2/|title=A Day of Firsts|date=14 November 2011|work=Munster Rugby|access-date=14 November 2011}} He scored his first try for Munster on 19 November 2011, in Munster's second Heinken Cup Pool One game against Castres.{{cite news|url=https://www.munsterrugby.ie/report/same-again-thanks-rog/|title=Same Again Thanks Rog|date=20 November 2011|work=Munster Rugby|access-date=20 November 2011}} O'Mahony won the Munster Young Player of the Year for the 2011–12 season.{{cite news|url=http://www.irishexaminer.com/sport/rugby/persistence-pays-off-for-munsters-gentle-giant-193046.html|title=Persistence pays off for Munster's gentle giant|date=7 May 2012|work=Irish Examiner|access-date=7 May 2012}} He captained Munster in their 2011–12 Pro12 away play-off semi-final against Ospreys on 11 May 2012, which Munster lost 45–10.{{cite news|url=https://www.munsterrugby.ie/report/no-consolation-of-any-sort-in-this-result/|title=No Consolation Of Any Sort In This Result|date=12 May 2012|work=Munster Rugby|access-date=10 May 2013}}

O'Mahony started for Munster in their opening fixture of the 2012–13 Heineken Cup on 13 October 2012, a 22–17 defeat at the hands of Racing 92.{{cite news|url=https://www.munsterrugby.ie/report/defeat-snatched-from-the-jaws-of-victory?/|title=Defeat Snatched From The Jaws of Victory?|date=14 October 2012|work=Munster Rugby|access-date=10 May 2013}} He scored a try in their 33–0 win against Edinburgh in round 2 on 21 October 2012.{{cite news|url=https://www.munsterrugby.ie/report/end-game-earns-bonus/|title=End Game Earns Bonus|date=22 October 2012|work=Munster Rugby|access-date=10 May 2013}} He started in the 15–9 win against Saracens on 8 December 2012,{{cite news|url=https://www.munsterrugby.ie/report/munster-show-their-gritty-side/|title=Munster Show Their Gritty Side|date=10 December 2012|work=Munster Rugby|access-date=10 May 2013}} and also in the reverse fixture a week later, which Munster lost 19–13.{{cite news|url=https://www.munsterrugby.ie/report/munster-lose-after-epic-battle/|title=Munster Lose After Epic Battle|date=17 December 2012|work=Munster Rugby|access-date=10 May 2013}} O'Mahony started against Edinburgh in the 26–17 round 5 victory,{{cite news|url=https://www.munsterrugby.ie/report/munster-win-in-murrayfield/|title=Munster Win In Murrayfield|date=13 January 2013|work=Munster Rugby|access-date=10 May 2013}} and also started in the crucial 29–6 win against Racing 92 that secured Munster a place in the quarter-finals.{{cite news|url=https://www.munsterrugby.ie/report/munster-go-through/|title=Munster Go Through|date=21 January 2013|work=Munster Rugby|access-date=10 May 2013}} He signed a new two-year contract with the IRFU in January 2013.{{cite news|url=https://munsterrugby.ie/2013/01/29/new-irfu-contract-for-omahony-2/|title=New IRFU Contract For O'Mahony|date=29 January 2013|work=Munster Rugby|access-date=29 January 2013}} O'Mahony continued to start for Munster in the knockout-stage of the 2012–13 tournament, playing a crucial role in their 18–12 away quarter-final victory against Harlequins on 7 April 2013.{{cite news|url=https://www.munsterrugby.ie/report/alone-they-stand/|title=Alone They Stand|date=8 April 2013|work=Munster Rugby|access-date=10 May 2013}} He also started the semi-final against Clermont Auvergne on 27 April 2013, which Munster lost 16–10.{{cite news|url=https://www.munsterrugby.ie/report/munster-lose-a-game-of-two-halves/|title=Munster Lose A Game of Two-Halves|date=28 April 2013|work=Munster Rugby|access-date=10 May 2013}}

O'Mahony was named as the new Munster captain on 30 July 2013, replacing former All Black Doug Howlett, who retired at the end of the 2012–13 season.{{cite news|url=https://munsterrugby.ie/2013/07/30/omahony-named-squad-captain-2/|title=O'Mahony Named Squad Captain|date=30 July 2013|work=Munster Rugby|access-date=30 July 2013}} He started for Munster against Edinburgh in the opening round of the 2013–14 Heineken Cup on 12 October 2013, captaining the side during their 29–23 defeat.{{cite news|url=https://www.munsterrugby.ie/report/disappointing-defeat-in-murrayfield/|title=Disappointing Defeat In Murrayfield|date=12 October 2013|work=Munster Rugby|access-date=7 November 2013}} He moved to number 8 for Munster's second-round game against Gloucester on 19 October 2013, which Munster won 26–10.{{cite news|url=https://www.munsterrugby.ie/report/heineken-cup-win-in-thomond-park/|title=Heineken Cup Win In Thomond Park|date=19 October 2013|work=Munster Rugby|access-date=7 November 2013}} He started against Perpignan on 8 December 2013, captaining the side to a 36–8 win.{{cite news|url=https://www.munsterrugby.ie/report/munster-top-of-group-after-bonus-point-win/|title=Munster Top Of Group After Bonus-Point Win|date=8 December 2013|work=Munster Rugby|access-date=8 December 2013}} O'Mahony started the reverse fixture away to Perpignan on 14 December 2013.{{cite news|url=https://www.munsterrugby.ie/report/munster-claim-last-gasp-win-in-perpignan/|title=Munster Claim Last-Gasp Win In Perpignan|date=14 December 2013|work=Munster Rugby|access-date=14 December 2013}}

O'Mahony started the 20–7 away win against Gloucester on 11 January 2014, scoring a try in a win that secured quarter-final qualification.{{cite news|url=https://www.munsterrugby.ie/report/quarter-final-place-secured/|title=Quarter Final Place Secured|date=12 January 2014|work=Munster Rugby|access-date=12 January 2014}} O'Mahony started against Edinburgh on 19 January 2014, scoring a try in the 38–6 round 6 win that secured a home quarter-final.{{cite news|url=https://www.munsterrugby.ie/report/bonus-point-munster-move-into-home-quarters/|title=Bonus-Point Munster Move Into Home Quarters|date=19 January 2014|work=Munster Rugby|access-date=19 January 2014}} O'Mahony started in Munster's 47–23 Heineken Cup quarter-final win against Toulouse on 5 April 2014, but went off with a shoulder injury in the 18th minute.{{cite news|url=https://www.munsterrugby.ie/report/vintage-munster-storm-into-semis/|title=Vintage Munster Storm Into Semis|date=5 April 2014|work=Munster Rugby|access-date=5 April 2014}} The injury meant O'Mahony was ruled out of the remainder of the season as he had to have reconstructive surgery on his shoulder.{{cite news|url=https://munsterrugby.ie/2014/04/09/omahony-ruled-out-3/|title=O'Mahony Ruled Out|date=9 April 2014|work=Munster Rugby|access-date=9 April 2014}} He also had surgery on his right shoulder to repair a long-standing issue.{{cite news|url=https://munsterrugby.ie/2014/05/06/squad-update-141/|title=Squad Update|date=6 May 2014|work=Munster Rugby|access-date=7 May 2014}} O'Mahony was nominated for the IRUPA Players' Player of the Year 2014 award on 23 April 2014.{{cite news|url=https://munsterrugby.ie/2014/04/23/munster-nominees-for-2014-irupa-awards-2/|title=Munster Nominees For 2014 IRUPA Awards|date=23 April 2014|work=Munster Rugby|access-date=24 April 2014}}

O'Mahony returned from injury on 4 October 2014, coming on as a replacement against Leinster.{{cite news|url=https://www.munsterrugby.ie/report/munster-overcome-leinster/|title=Munster Overcome Leinster|date=4 October 2014|work=Munster Rugby|access-date=5 October 2014}} He started in Munster's first European Rugby Champions Cup game against Sale Sharks on 18 October 2014.{{cite news|url=https://www.munsterrugby.ie/report/keatley-kicks-munster-on/|title=Keatley Kicks Munster On|date=18 October 2014|work=Munster Rugby|access-date=18 October 2014}} O'Mahony started against Saracens in round 2 of the Champions Cup on 24 October 2014.{{cite news|url=https://www.munsterrugby.ie/report/munster-overcome-saracens/|title=Munster Overcome Saracens|date=24 October 2014|work=Munster Rugby|access-date=25 October 2014}} He started against Clermont Auvergne on 6 December 2014.{{cite news|url=https://www.munsterrugby.ie/report/clermont-claim-win-at-thomond-park/|title=Clermont Claim Win At Thomond Park|date=6 December 2014|work=Munster Rugby|access-date=6 December 2014}} O'Mahony also started in the reverse fixture against Clermont on 14 December 2014.{{cite news|url=https://www.munsterrugby.ie/report/losing-bonus-point-secured-at-clermont/|title=Losing Bonus Point Secured At Clermont|date=14 December 2014|work=Munster Rugby|access-date=14 December 2014}}

O'Mahony started against Saracens on 17 January 2015.{{cite news|url=https://www.munsterrugby.ie/report/munster-lose-out-in-london/|title=Munster Lose Out In London|date=17 January 2015|work=Munster Rugby|access-date=17 January 2015}} O'Mahony started at Number 8 against Sale Sharks on 25 January 2015.{{cite news|url=https://www.munsterrugby.ie/report/munster-finish-with-flourish/|title=Munster Finish With Flourish|date=25 January 2015|work=Munster Rugby|access-date=25 January 2015}} O'Mahony signed a new three-year contract with Munster and the IRFU in February 2015.{{cite news|url=https://munsterrugby.ie/2015/02/18/omahony-signs-three-year-contract-2/|title=O'Mahony Signs Three Year Contract|date=18 February 2015|work=Munster Rugby|access-date=18 February 2015}}

O'Mahony made his comeback from the knee injury he suffered with Ireland during the 2015 Rugby World Cup on 1 October 2016, coming on as a replacement for Billy Holland in the 2016–17 Pro12 fixture against Zebre.{{cite news|url=https://www.munsterrugby.ie/report/try-fest-in-thomond/|title=Try Fest In Thomond|date=1 October 2016|work=Munster Rugby|access-date=1 October 2016}} On 1 April 2017, O'Mahony was captain in Munster's 41–16 2016–17 European Rugby Champions Cup quarter-final victory against Toulouse, though he went off during the second-half with a leg injury.{{cite news|url=https://munsterrugby.ie/report/munster-back-in-champions-cup-semi-finals/|title=Munster Back In Champions Cup Semi Finals|date=1 April 2017|work=Munster Rugby|access-date=2 April 2017}} Fortunately, the injury wasn't serious and O'Mahony was able to lead Munster in their Champions Cup semi-final against Saracens on 22 April 2017, which the defending champions won 26–10 in the Aviva Stadium, ending Munster's European season.{{cite news|url=https://munsterrugby.ie/report/memorable-european-run-comes-to-an-end/|title=Memorable European Run Comes To An End|date=22 April 2017|work=Munster Rugby|access-date=22 April 2017}} On 27 May 2017, O'Mahony captained Munster against Scarlets in the 2017 Pro12 Grand Final, which the Welsh side won 46–22.{{cite news|url=https://munsterrugby.ie/report/aviva-anguish-in-pro12-final/|title=Aviva Anguish In PRO12 Final|date=27 May 2017|work=Munster Rugby|access-date=28 May 2017}} O'Mahony signed a new three-year contract with the IRFU in December 2017.{{cite news|url=https://munsterrugby.ie/2017/12/15/peter-omahony-signs-3-year-irfu-contract/|title=Peter O'Mahony signs 3 year IRFU contract|date=15 December 2017|work=Munster Rugby|access-date=15 December 2017}} He was Man-of-the-Match in Munster's 25–16 away win against Leicester Tigers in the 2017–18 European Rugby Champions Cup on 17 December 2017.{{cite news|url=https://munsterrugby.ie/report/omahony-leads-munster-famous-win-welford-road/|title=O'Mahony Leads Munster To Famous Win At Welford Road|date=17 December 2017|work=Munster Rugby|access-date=17 December 2017}}

O'Mahony won his 100th cap for Munster on 26 December 2017, doing so when he started against Leinster in a 2017–18 Pro14 fixture.{{cite news|url=https://munsterrugby.ie/2017/12/23/omahony-set-century-leinster/|title=O'Mahony Set For Century Against Leinster|date=23 December 2017|work=Munster Rugby|access-date=27 December 2017}}{{cite news|url=https://munsterrugby.ie/report/munster-downed-leinster/|title=Munster Downed By Leinster|date=26 December 2017|work=Munster Rugby|access-date=27 December 2017}} O'Mahony was Man-of-the-Match in Munster's 20–19 Champions Cup quarter-final win against Toulon on 31 March 2018.{{cite news|url=https://munsterrugby.ie/report/conway-magic-topples-toulon/|title=Conway Magic Topples Toulon|date=31 March 2018|work=Munster Rugby|access-date=31 March 2018}} For his performances throughout the 2018–19 season, O'Mahony was presented with the Munster Men's Player of the Year award in late April 2019, adding to the Young Player of the Year award he won in 2012.{{cite news|url=https://munsterrugby.ie/2019/04/23/omahony-named-munster-player-of-the-year/|title=O'Mahony Named Munster Player Of The Year|date=23 April 2019|work=Munster Rugby|access-date=24 April 2019}} He was also named in the 2018–19 Pro14 Dream Team in May 2019.{{cite news|url=https://munsterrugby.ie/2019/05/24/beirne-omahony-in-guinness-pro14-dream-team/|title=Beirne & O'Mahony In Guinness PRO14 Dream Team|date=24 May 2019|work=Munster Rugby|access-date=24 May 2019}}

O'Mahony was sent off in Munster's opening 2020–21 Pro14 fixture against Scarlets on 3 October 2020 after receiving two yellow cards. Despite this, Munster won the game 30–27, and a Pro14 judicial officer subsequently ruled that the two yellow cards were sufficient and no ban was necessary.{{cite news|url=https://www.the42.ie/peter-omahony-munster-red-card-5227541-Oct2020/|title=Munster captain Peter O'Mahony cleared to play after red card last weekend|date=8 October 2020|work=The42|access-date=8 October 2020}} He signed a two-year contract extension with the IRFU in March 2021, a deal that will see O'Mahony remain with Munster until at least June 2023.{{cite news|url=https://www.munsterrugby.ie/2021/03/04/peter-omahony-signs-irfu-contract-extension/#post|title=Peter O'Mahony Signs IRFU Contract Extension|date=4 March 2021|work=Munster Rugby|access-date=4 March 2021}} O'Mahony won his 150th cap for Munster in their 20–18 win against provincial rivals Connacht in round 4 of the 2021–22 United Rugby Championship on 16 October 2021, which also marked the fifth anniversary of former Munster player and coach Anthony Foley's passing.{{cite news|url=https://www.munsterrugby.ie/report/report-munster-edge-out-connacht-in-tight-interpro-battle/#report|title=Report {{!}} Munster Edge Out Connacht In Tight Interpro Battle|date=16 October 2021|work=Munster Rugby|access-date=23 October 2021}}

Having missed the first leg of Munster's 2021–22 Champions Cup round of 16 fixture away to English club Exeter Chiefs due to injury, which the hosts won 13–8, O'Mahony returned for the second leg one week later on 16 April 2022 to lead from the front and earn the player of the match award in the province's 26–10 home win, which secured a 34–23 aggregate win and a record-equallinging 19th Champions Cup quarter-final for Munster.{{cite news|url=https://www.the42.ie/munster-exeter-champions-cup-5-5740297-Apr2022/|title=Inspirational Peter O'Mahony leads Munster to thrilling win over Exeter|date=16 April 2022|work=The42|access-date=16 April 2022}}

O'Mahony won the player of the match award in Munster's Champions Cup quarter-final defeat against defending champions Toulouse on 7 May 2022. The match was tied 24–24 after extra-time, and Toulouse won the penalty shootout 4–2, but O'Mahony's performance during the match, which included four turnovers and a huge defensive effort, garnered widespread praise, with both Munster head coach Johann van Graan and O'Mahony's former British & Irish Lions teammate Sam Warburton calling him a "warrior".{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-40867724.html|title=Van Graan pays emotional tribute to "warrior" Peter O'Mahony|date=9 May 2022|work=Irish Examiner|access-date=12 May 2022}}{{cite news|url=https://punditarena.com/rugby/andrewdempsey/sam-warburton-hails-peter-omahony-munster-v-toulouse/|title=Sam Warburton hails Peter O'Mahony in Munster's Champions Cup thriller v Toulouse|date=7 May 2022|work=Pundit Arena|access-date=12 May 2022}}{{cite news|url=https://www.sportsjoe.ie/rugby/munster-toulouse-shootout-champions-cup-report-259638|title=Peter O'Mahony heroics in vain as Munster suffer shoot-out heartbreak|date=7 May 2022|work=SportsJOE|access-date=12 May 2022}}{{cite news|url=https://www.balls.ie/rugby/peter-omahony-performance-toulouse-509028|title=Three Peter O'Mahony Moments Summed Up Stunning Toulouse Performance|date=7 May 2022|work=Balls.ie|access-date=12 May 2022}} O'Mahony signed a one-year contract extension with the IRFU and Munster in February 2023, meaning he will remain with the province for the 2023–24 season.{{cite news|url=https://www.munsterrugby.ie/2023/02/20/peter-omahony-signs-irfu-contract-extension-2/|title=Peter O'Mahony Signs IRFU Contract Extension|date=20 February 2023|work=Munster Rugby|access-date=20 February 2023}} He captained Munster in their 19–14 win against the Stormers in the final of the 2022–23 United Rugby Championship on 27 May 2023.{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41149351.html|title=Magical Munster see off Stormers to win URC title and end trophy drought|date=27 May 2023|work=Irish Examiner|access-date=27 May 2023}}

In February 2025, he announced he would retire from professional rugby following the conclusion of the 2024–25 season.{{cite web |last1=Elliot |first1=Ed |title=Key Ireland trio to retire after Six Nations in end of an era |url=https://www.independent.co.uk/sport/rugby/rugby-union/ireland-retirements-cian-healy-peter-omahony-conor-murray-six-nations-b2705869.html |publisher=The Independent |access-date=28 February 2025}}

O'Mahony captained Ireland at under-18 and under-20 levels,{{cite news|url=https://munsterrugby.ie/2009/02/12/catching-up-with-peter-omahony/|title=Catching Up With Peter O'Mahony|date=12 February 2009|work=Munster Rugby}} before being called up to the senior side in 2012. He made his full debut against Italy on 25 February 2012, coming on as a replacement for Seán O'Brien. He made his first start for Ireland in the game against Scotland on 10 March 2012, after an injury to Seán O'Brien.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5717.php|title=Four-Try Ireland See Off Scottish Challenge|date=10 March 2012|work=Irish Rugby|access-date=11 March 2012}} By the end of Ireland's tour of New Zealand in 2012, he had played in all three back-row positions.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5301.php|title=Ireland Open Series With Auckland Defeat|date=9 June 2012|work=Irish Rugby|access-date=1 July 2012|archive-url=https://web.archive.org/web/20161206150102/http://www.irishrugby.ie/rugby/fixturesandresults/5301.php|archive-date=6 December 2016|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5289.php|title=Heartbreak in Christchurch For Heroic Ireland|date=16 June 2012|work=Irish Rugby|access-date=1 July 2012|archive-url=https://web.archive.org/web/20151202125619/http://www.irishrugby.ie/rugby/fixturesandresults/5289.php|archive-date=2 December 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5304.php|title=Ireland End Tour With Heavy Loss|date=23 June 2012|work=Irish Rugby|access-date=1 July 2012|archive-url=https://web.archive.org/web/20151202125626/http://www.irishrugby.ie/rugby/fixturesandresults/5304.php|archive-date=2 December 2015|url-status=dead}} O'Mahony won the IRUPA Young Player of the Year award for the 2011–12 season.{{cite news|url=http://www.irishrugby.ie/news/6771.php#.Wdx_ifiGPcs|title=Kearney Wins IRUPA Players Award|date=10 May 2012|work=Irish Rugby|access-date=12 May 2012}} He also played in the 2012 November Tests against South Africa and Argentina.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5251.php|title=Ireland Lose Tight Encounter With Springboks|date=10 November 2012|work=Irish Rugby|access-date=12 November 2012|archive-url=https://web.archive.org/web/20151202130205/http://www.irishrugby.ie/rugby/fixturesandresults/5251.php|archive-date=2 December 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/5238.php|title=Tries Flow As Ireland Pummel Pumas|date=24 November 2012|work=Irish Rugby|access-date=1 December 2012|archive-url=https://web.archive.org/web/20140613083918/http://www.irishrugby.ie/rugby/fixturesandresults/5238.php|archive-date=13 June 2014|url-status=dead}}

In the 2013 Six Nations Championship O'Mahony played in all five games as Ireland finished fifth.{{cite news|url=http://www.irishrugby.ie/news/3491.php#.WdyAW_iGPcs|title=Ireland Training Squad Announced|date=17 January 2013|work=Irish Rugby|access-date=21 January 2013}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/28399.php|title=Cardiff Cracker Gets Ireland Up And Running|date=2 February 2013|work=Irish Rugby|access-date=3 February 2013|archive-url=https://web.archive.org/web/20150615032118/http://www.irishrugby.ie/rugby/fixturesandresults/28399.php|archive-date=15 June 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/28417.php|title=Penalties Decide It As Ireland Lose Brutal Contest|date=10 February 2013|work=Irish Rugby|access-date=10 February 2013|archive-url=https://web.archive.org/web/20151123224002/http://www.irishrugby.ie/rugby/fixturesandresults/28417.php|archive-date=23 November 2015|url-status=dead}}{{cite news|url=https://www.bbc.co.uk/sport/0/rugby-union/21540230|title=Six Nations: Scotland beat Ireland in Murrayfield turnaround|date=24 February 2013|work=BBC Sport|access-date=3 March 2013}}{{cite news|url=https://www.bbc.co.uk/sport/0/rugby-union/21706934|title=Six Nations 2013: France recover to draw with Ireland|date=9 March 2013|work=BBC Sport|access-date=10 March 2013}}{{cite news|url=https://www.bbc.co.uk/sport/0/rugby-union/21789586|title=Six Nations 2013: Italy 22–15 Ireland|date=16 March 2013|work=BBC Sport|access-date=10 May 2013}} He also featured in the 2013 Ireland tour to North America,{{cite news|url=http://www.irishrugby.ie/news/27384.php#.WdyBPfiGPcs|title=Ireland Squads Announced For Summer Tours|date=19 May 2013|work=Irish Rugby|access-date=19 May 2013}} and was made captain after Rory Best was called up to the 2013 British & Irish Lions squad.{{cite news|url=http://www.irishrugby.ie/news/27311.php#.WdyBYviGPcs|title=O'Mahony To Captain Ireland Summer Tour Squad|date=26 May 2013|work=Irish Rugby|access-date=26 May 2013}}{{cite news|url=https://www.munsterrugby.ie/2013/05/27/omahony-to-lead-way/|title=O'Mahony To Lead Way|date=27 May 2013|work=Munster Rugby|access-date=27 May 2013}} In the 2013 Autumn Tests he scored his first try for Ireland, in a game against Samoa.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/29321.php|title=Ireland Begin Series With Five-Try Success|date=9 November 2013|work=Irish Rugby|access-date=10 November 2013}}

O'Mahony featured in four of Ireland's games, picking up a Man-of-the-Match award against Wales, in their championship-winning 2014 Six Nations.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/29516.php|title=Three-Try Ireland Take Positive First Steps|date=2 February 2014|work=Irish Rugby|access-date=3 February 2014|archive-url=https://web.archive.org/web/20140310050717/http://www.irishrugby.ie/rugby/fixturesandresults/29516.php|archive-date=10 March 2014|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/29623.php|title=Terrific Display Sees Ireland Dominate Wales|date=8 February 2014|work=Irish Rugby|access-date=8 February 2014|archive-url=https://web.archive.org/web/20140222035053/http://www.irishrugby.ie/rugby/fixturesandresults/29623.php|archive-date=22 February 2014|url-status=dead}}{{cite news|url=http://www.independent.ie/sport/rugby/six-nations/england-edge-ireland-in-war-of-attrition-to-end-our-grand-slam-dreams-30033471.html|title=England edge Ireland in war of attrition to end our Grand Slam dreams|date=22 February 2014|work=Irish Independent|access-date=4 March 2014}}{{cite news|url=http://www.irishrugby.ie/news/30016.php#.WdyCnfiGPcs|title=Ireland Make One Change For Italy Test|date=6 March 2014|work=Irish Rugby|access-date=8 March 2014}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/30149.php|title=Ireland Edge Out France To Take Six Nations Title|date=15 March 2014|work=Irish Rugby|access-date=16 March 2014|archive-url=https://web.archive.org/web/20140316170240/http://www.irishrugby.ie/rugby/fixturesandresults/30149.php|archive-date=16 March 2014|url-status=dead}} After playing against South Africa and Australia in the 2014 Guinness Series{{cite web|url=http://www.irishrugby.ie/rugby/fixturesandresults/32917.php|title=Clinical Ireland Claim Springbok Scalp|date=8 November 2014|work=Irish Rugby|access-date=9 November 2014|archive-url=https://web.archive.org/web/20141108205432/http://www.irishrugby.ie/rugby/fixturesandresults/32917.php|archive-date=8 November 2014|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/33095.php|title=Thrilling Win Seals Series Clean Sweep For Ireland|date=22 November 2014|work=Irish Rugby|access-date=23 November 2014|archive-url=https://web.archive.org/web/20141126042350/http://www.irishrugby.ie/rugby/fixturesandresults/33095.php|archive-date=26 November 2014|url-status=dead}} O'Mahony started every game in the 2015 Six Nations Championship as Ireland retained their title,{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/33744.php|title=Murray And O'Donnell Tries Steer Ireland To Rome Win|date=7 February 2015|work=Irish Rugby|access-date=7 February 2015|archive-url=https://web.archive.org/web/20150222055418/http://www.irishrugby.ie/rugby/fixturesandresults/33744.php|archive-date=22 February 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/33830.php|title=Sexton's Boot Guides Ireland To Hard-Fought Victory Over France|date=14 February 2015|work=Irish Rugby|access-date=14 February 2015|archive-url=https://web.archive.org/web/20150214224234/http://www.irishrugby.ie/rugby/fixturesandresults/33830.php|archive-date=14 February 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/33987.php|title=Henshaw's First Try Sees Ireland Overcome England|date=1 March 2015|work=Irish Rugby|access-date=1 March 2015|archive-url=https://web.archive.org/web/20150303053152/http://www.irishrugby.ie/rugby/fixturesandresults/33987.php|archive-date=3 March 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/34123.php|title=Ireland's Winning Run Ended By Wales|date=14 March 2015|work=irishrugby.ie|access-date=15 March 2015|archive-url=https://web.archive.org/web/20150316182942/http://www.irishrugby.ie/rugby/fixturesandresults/34123.php|archive-date=16 March 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/34176.php|title=O'Brien Double Drives Ireland To Final Day Victory|date=21 March 2015|work=Irish Rugby|access-date=21 March 2015|archive-url=https://web.archive.org/web/20150402172001/http://www.irishrugby.ie/rugby/fixturesandresults/34176.php|archive-date=2 April 2015|url-status=dead}} the first time Ireland had won back-to-back championships since 1948–49.{{cite news|url=http://www.irishrugby.ie/news/34179.php#.WdyD6viGPcs|title=Thrilling Title Finish Sees Ireland Crowned Champions Again|date=21 March 2015|work=Irish Rugby|access-date=21 March 2015}}

O'Mahony was selected in the final 31-man squad for the 2015 Rugby World Cup,{{cite news|url=http://www.irishrugby.ie/news/35385.php#.WdyEDPiGPcs|title=Ireland Squad Named For Rugby World Cup|date=1 September 2015|work=Irish Rugby|access-date=1 September 2015}} and started pool games against Canada,{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/35581.php|title=Bonus Point Win Gets Ireland Off To Satisfying World Cup Start|date=19 September 2015|work=Irish Rugby|access-date=19 September 2015|archive-url=https://web.archive.org/web/20150928143035/http://www.irishrugby.ie/rugby/fixturesandresults/35581.php|archive-date=28 September 2015|url-status=dead}} Italy,{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/35736.php|title=Earls' Eighth RWC Try Sends Ireland Through To Quarter-Finals|date=4 October 2015|work=Irish Rugby|access-date=4 October 2015|archive-url=https://web.archive.org/web/20151006094120/http://www.irishrugby.ie/rugby/fixturesandresults/35736.php|archive-date=6 October 2015|url-status=dead}} and France, but went off with a knee injury during the second-half against France and was ruled out for the remainder of the World Cup.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/35803.php|title=Ireland Beat Les Bleus To Set Up Quarter-Final Against Argentina|date=11 October 2015|work=Irish Rugby|access-date=11 October 2015|archive-url=https://web.archive.org/web/20151014221634/http://www.irishrugby.ie/rugby/fixturesandresults/35803.php|archive-date=14 October 2015|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/news/35810.php#.WdyEvviGPcs|title=Knee Injury Rules O'Mahony Out Of Knockout Stages|date=12 October 2015|work=Irish Rugby|access-date=12 October 2015}}

On 26 October 2016, O'Mahony was named in Ireland's squad for the 2016 end-of-year rugby union internationals.{{cite news|url=http://www.irishrugby.ie/news/38355.php#.WdyE9viGPcs|title=Six Uncapped Players In Ireland Squad|date=26 October 2016|work=Irish Rugby|access-date=26 October 2016}} On 12 November 2016, O'Mahony made his return to the senior Ireland team, captaining them in the 52–21 win against Canada.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/38490.php|title=Ireland Win GUINNESS Series Opener With Eight New Caps|date=12 November 2016|access-date=12 November 2016|archive-url=https://web.archive.org/web/20161113121339/http://www.irishrugby.ie/rugby/fixturesandresults/38490.php|archive-date=13 November 2016|url-status=dead}} On 23 January 2017, O'Mahony was named in the Ireland squad for the opening two rounds of the 2017 Six Nations Championship.{{cite news|url=https://munsterrugby.ie/2017/01/23/13-munster-players-in-ireland-squad-2/|title=13 Munster Players In Ireland Squad|date=23 January 2017|work=Munster Rugby|access-date=23 January 2017}} On 18 March 2017, O'Mahony was Man-of-the-Match in Ireland's 13–9 win against England, a victory that denied England consecutive Grand Slams in the Six Nations.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/39308.php|title=Ireland Dig Deep To Deny England A Dublin Grand Slam|date=18 March 2017|work=Irish Rugby|access-date=18 March 2017|archive-url=https://web.archive.org/web/20170321170739/http://www.irishrugby.ie/rugby/fixturesandresults/39308.php|archive-date=21 March 2017|url-status=dead}}

O'Mahony started in Ireland's wins against South Africa and Argentina during the 2017 Autumn Internationals.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/40861.php|title=Late Flurry Fires Ireland To Record-Breaking Win Over Springboks|date=12 November 2017|work=Irish Rugby|access-date=28 November 2017|archive-url=https://web.archive.org/web/20171126180903/http://www.irishrugby.ie/rugby/fixturesandresults/40861.php|archive-date=26 November 2017|url-status=dead}}{{cite news|url=https://munsterrugby.ie/2017/11/28/squad-update-155/|title=Squad Update|date=28 November 2017|work=Munster Rugby|access-date=28 November 2017}} O'Mahony started every game for Ireland as they won a Grand Slam in the 2018 Six Nations Championship. At the end of the game against England, O'Mahony gave his winner's medal to an Irish supporter with Down syndrome.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/41314.php|title=Sexton's Drop Of Magic Seals Dramatic Paris Win For Ireland|date=3 February 2018|work=Irish Rugby|access-date=18 March 2018|archive-url=https://web.archive.org/web/20180323220259/http://www.irishrugby.ie/rugby/fixturesandresults/41314.php|archive-date=23 March 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/41389.php|title=Ireland Reel Off Eight Tries Against Italy To Go Top Of The Table|date=11 February 2018|work=Irish Rugby|access-date=18 March 2018|archive-url=https://web.archive.org/web/20180318183655/http://www.irishrugby.ie/rugby/fixturesandresults/41389.php|archive-date=18 March 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/41486.php|title=Ireland Strengthen Title Challenge With Stirring Win Over Wales|date=24 February 2018|work=Irish Rugby|access-date=18 March 2018|archive-url=https://web.archive.org/web/20180318183711/http://www.irishrugby.ie/rugby/fixturesandresults/41486.php|archive-date=18 March 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/41579.php|title=Six Nations Title Assured As Ireland Extend Winning Streak To 11 Tests|date=10 March 2018|work=Irish Rugby|access-date=18 March 2018|archive-url=https://web.archive.org/web/20180316203905/http://www.irishrugby.ie/rugby/fixturesandresults/41579.php|archive-date=16 March 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/41641.php|title=Grand Slam Mission Complete As Ireland Make It A Clean Sweep At Twickenham|date=17 March 2018|work=Irish Rugby|access-date=18 March 2018|archive-url=https://web.archive.org/web/20180319015501/http://www.irishrugby.ie/rugby/fixturesandresults/41641.php|archive-date=19 March 2018|url-status=dead}}{{cite news|url=https://www.telegraph.co.uk/rugby-union/2018/03/18/peter-omahony-gives-away-six-nations-winners-medal-heartwarming/|title=Peter O'Mahony gives away Six Nations winners' medal in heartwarming gesture|date=18 March 2018|work=The Telegraph|access-date=18 March 2018}} In the absence of the injured Rory Best, O'Mahony captained Ireland to a historic 2–1 series victory against Australia in June 2018, Ireland's first since 1979, with O'Mahony also winning his 50th test cap for Ireland in the third test.{{cite news|url=http://irishrugby.ie/rugby/fixturesandresults/42146.php|title=First Blood To Wallabies As Ireland's Winning Streak Comes To An End|date=9 June 2018|work=Irish Rugby|access-date=24 June 2018|archive-url=https://web.archive.org/web/20180620033531/http://www.irishrugby.ie/rugby/fixturesandresults/42146.php|archive-date=20 June 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/42176.php|title=Furlong On Fire As Ireland End Wait For Away Win Over Wallabies|date=16 June 2018|work=Irish Rugby|access-date=24 June 2018|archive-url=https://web.archive.org/web/20180622170805/http://www.irishrugby.ie/rugby/fixturesandresults/42176.php|archive-date=22 June 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/42197.php|title=Schmidt Praises Character Of Players As Ireland Claim Historic Series Win|date=23 June 2018|work=Irish Rugby|access-date=24 June 2018|archive-url=https://web.archive.org/web/20180624153308/http://www.irishrugby.ie/rugby/fixturesandresults/42197.php|archive-date=24 June 2018|url-status=dead}} During the 2018 Autumn Tests, O'Mahony started in Ireland's 28–17 win against Argentina on 10 November, and was Man-of-the-Match in Ireland's 16–9 win against New Zealand on 17 November, a win that was O'Mahony's first against the All Blacks and Ireland's first ever win in Dublin against New Zealand.{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/42889.php|title=Ireland Set New Home Record With Solid Victory Over Pumas|date=10 November 2018|work=Irish Rugby|access-date=17 November 2018|archive-url=https://web.archive.org/web/20181115084049/http://www.irishrugby.ie/rugby/fixturesandresults/42889.php|archive-date=15 November 2018|url-status=dead}}{{cite news|url=http://www.irishrugby.ie/rugby/fixturesandresults/42946.php|title=Immense Ireland End Long Wait For Home Win Over All Blacks|date=18 November 2018|work=Irish Rugby|access-date=18 November 2018|archive-url=https://web.archive.org/web/20181118181704/http://www.irishrugby.ie/rugby/fixturesandresults/42946.php|archive-date=18 November 2018|url-status=dead}}

O'Mahony was ever-present for Ireland during the 2019 Six Nations Championship, starting in the 32–20 opening defeat against England,{{cite news|url=https://www.irishrugby.ie/report/ireland-fail-to-fire-as-four-try-england-emerge-triumphant/#report|title=Ireland Fail To Fire As Four-Try England Emerge Triumphant|date=3 February 2019|work=Irish Rugby|access-date=30 August 2021}} the 22–13 win against Scotland,{{cite news|url=https://www.irishrugby.ie/report/irelands-dogged-display-sees-off-scottish-challenge/#report|title=Ireland's Dogged Display Sees Off Scottish Challenge|date=10 February 2019|work=Irish Rugby|access-date=30 August 2021}} the 26–16 win against Italy,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/47350986|title=Six Nations: Ireland labour to 26-16 bonus-point victory over Italy|date=24 February 2019|work=BBC Sport|access-date=30 August 2021}} the 26–14 win against France{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/47516963|title=Six Nations: Ireland beat France 26-14 to retain title hopes|date=10 March 2019|work=BBC Sport|access-date=30 August 2021}} and the 25–7 defeat against Wales in the final round, a victory that saw the Welsh win the grand slam.{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/47596437|title=Wales 25-7 Ireland: Wales win Six Nations Grand Slam|date=16 March 2019|work=BBC Sport|access-date=30 August 2021}} He was selected in the 31-man Ireland squad for the 2019 Rugby World Cup,{{cite news|url=https://www.irishrugby.ie/2019/09/02/irelands-rugby-world-cup-squad-named/|title=Ireland's Rugby World Cup Squad Named|date=2 September 2019|work=IRFU|access-date=2 September 2019}} having featured in the warm-up matches against England{{cite news|url=https://www.the42.ie/ireland-england-world-cup-warm-up-4780666-Aug2019/|title=Ireland crash and burn as England rip Schmidt's men apart in London|date=24 August 2019|work=The42|access-date=2 September 2019}} and Wales, captaining Ireland in the latter.{{cite news|url=https://www.the42.ie/ireland-wales-report-warm-up-4790446-Aug2019/|title=Stockdale at the double as Schmidt's Ireland cling on for victory in Cardiff|date=31 August 2019|work=The42|access-date=2 September 2019}} During the World Cup itself, O'Mahony started in Ireland's opening 27–3 win against Scotland{{cite news|url=https://www.irishrugby.ie/report/pack-points-the-way-as-ireland-sweep-scotland-aside/#report|title=Pack Points The Way As Ireland Sweep Scotland Aside|date=22 September 2019|work=Irish Rugby|access-date=30 August 2021}} their shock 19–12 defeat against hosts Japan,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/49849736|title=Japan 19-12 Ireland: Dazzling display gives hosts shock victory|date=28 September 2019|work=BBC Sport|access-date=30 August 2021}} and in the 35–0 win against Russia,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/49903904|title=Ireland 35-0 Russia: Joe Schmidt's side labour to World Cup win|date=3 October 2019|work=BBC Sport|access-date=30 August 2021}} before featuring off the bench in Ireland's 47–5 win against Samoa in their final pool game,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/50012877|title=Ireland 47-5 Samoa: Bonus-point win puts Irish into last eight|date=12 October 2019|work=BBC Sport|access-date=30 August 2021}} and starting in the comprehensive 46–14 defeat against New Zealand in the quarter-finals, which brought an end to Ireland's 2019 World Cup.{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/50109620|title=New Zealand 46-14 Ireland: 'We gave All Blacks a leg up' says Irish coach Schmidt|date=19 October 2019|work=BBC Sport|access-date=30 August 2021}}

Retained by new head coach Andy Farrell in his squad for the 2020 Six Nations Championship, O'Mahony featured off the bench in Ireland's 19–12 opening win against Scotland on 1 February 2020,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/51318880|title=Six Nations 2020: Ireland win 19-12 against wasteful Scotland|date=1 February 2020|work=BBC Sport|access-date=30 August 2021}} then started in their 24–14 win against defending champions Wales on 8 February,{{cite news|url=https://www.irishrugby.ie/report/ireland-go-two-for-two-with-impressive-bonus-point-win/#report|title=Ireland Go Two For Two With Impressive Bonus Point Win|date=9 February 2020|work=Irish Rugby|access-date=30 August 2021}} and their 24–12 defeat against England,{{cite news|url=https://www.irishrugby.ie/report/damage-done-in-first-half-as-ireland-endure-disappointing-twickenham-defeat/#report|title=Damage Done In First Half As Ireland Endure Disappointing Twickenham Defeat|date=23 February 2020|work=Irish Rugby|access-date=30 August 2021}} before the tournament was suspended due to the COVID-19 pandemic.{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/51800754|title=Six Nations 2020: Who can win title after matches postponed because of coronavirus?|date=9 March 2020|work=BBC Sport|access-date=30 August 2021}} The tournament eventually resumed in October 2020, with O'Mahony featuring off the bench in Ireland's 50–17 win against Italy{{cite news|url=https://www.irishrugby.ie/report/debutants-have-desired-impact-as-ireland-run-in-seven-tries/#report|title=Debutants Have Desired Impact As Ireland Run In Seven Tries|date=24 October 2020|work=Irish Rugby|access-date=30 August 2021}} and the 35–27 defeat against France in their final fixture of the tournament.{{cite news|url=https://www.irishrugby.ie/report/ireland-rue-missed-chances-as-fluent-france-come-out-on-top/#report|title=Ireland Rue Missed Chances As Fluent France Come Out On Top|date=31 October 2020|work=Irish Rugby|access-date=30 August 2021}}

With the usual format of end-of-year international tests not possible due to the COVID-19 pandemic, Ireland instead participated in the Autumn Nations Cup. O'Mahony started in the 32–9 opening win against Wales on 13 November{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/54917121|title=Autumn Nations Cup: Ireland defeat Wales 32-9 in tournament opener|date=13 November 2020|work=BBC Sport|access-date=30 August 2021}} and in the 18–7 defeat against England on 21 November,{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/55028232|title=England 18-7 Ireland: Jonny May stars in emphatic and entertaining victory for hosts|date=21 November 2020|work=BBC Sport|access-date=30 August 2021}} featured off the bench in the 23–10 win against Georgia on 29 November,{{cite news|url=https://www.skysports.com/rugby-union/ireland-vs-georgia/97313|title=Ireland 23-10 Georgia: Uninspired Irish beat Georgia|date=29 November 2020|work=Sky Sports|access-date=30 August 2021}} and returned to the starting line-up for the 31–16 win against Scotland on 5 December, which secured a third-place finish for Ireland in the tournament.{{cite news|url=https://www.bbc.co.uk/sport/rugby-union/55176542|title=Ireland 31-16 Scotland: Hosts finish third in Autumn Nations Cup|date=5 December 2020|work=BBC Sport|access-date=30 August 2021}}

In Ireland's opening 2021 Six Nations game away to Wales on 7 February 2021, O'Mahony was sent-off in the 14th minute for making contact with the head of Wales prop Tomas Francis when attempting to clear him (Francis) out in a ruck. He was subsequently banned until 14 March 2021.{{cite news|url=https://www.the42.ie/peter-omahony-banned-5350146-Feb2021/|title=O'Mahony banned for three Six Nations games following red card against Wales|date=9 February 2021|work=The42|access-date=14 February 2021}} The red card was the first received by an Ireland player in a Five/Six Nations match since Willie Duggan's in 1977.{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-40222229.html|title=Ireland and Wales player ratings: Andy Farrell faces selection headaches for France test|date=7 February 2021|work=Irish Examiner|access-date=14 February 2021}} He returned from the ban to feature as a replacement in the 32–18 win against England in the final round.{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-40248281.html|title=Jack Conan sets up try and scores another as Ireland too good for England at Aviva|date=20 March 2021|work=Irish Examiner|access-date=30 August 2021}}

During the 2021 July rugby union tests, O'Mahony started in Ireland's 39–31 win against Japan{{cite news|url=https://www.irishrugby.ie/report/ireland-outlast-japan-in-exciting-nine-try-encounter/#report|title=Ireland Outlast Japan In Exciting Nine-Try Encounter|date=3 July 2021|work=Irish Rugby|access-date=30 August 2021}} before commencing his off-season.{{cite news|url=https://www.the42.ie/ireland-usa-injury-update-5486035-Jul2021/|title=Farrell and Larmour ruled out of US clash as O'Mahony begins off-season|date=5 July 2021|work=The42|access-date=30 August 2021}} During the 2021 Autumn Nations Series, O'Mahony featured off the bench in Ireland's 60–5 win against Japan on 6 November{{cite news|url=https://www.the42.ie/ireland-japan-report-2021-5594068-Nov2021/|title=Ireland obliterate Japan with slick performance as Sexton marks 100th in style|date=6 November 2021|work=The42|access-date=16 November 2021}} and in the famous 29–20 win against New Zealand on 13 November,{{cite news|url=https://www.the42.ie/ireland-all-blacks-2021-report-5600819-Nov2021/|title=Farrell's brilliant Ireland power to thrilling victory over the All Blacks in Dublin|date=13 November 2021|work=The42|access-date=16 November 2021}} before replacing the injured Jack Conan to start in the 53–7 win against Argentina in Ireland's final fixture of the series on 21 November.{{cite news|url=https://www.the42.ie/ireland-argentina-report-2021-5607840-Nov2021/|title=Farrell's Ireland finish autumn in style with battering of Argentina|date=21 November 2021|work=The42|access-date=21 November 2021}}

O'Mahony featured as a replacement in Ireland's 29–7 win against Wales in their opening fixture of the 2022 Six Nations Championship on 5 February,{{cite news|url=https://www.the42.ie/ireland-wales-2022-report-5674521-Feb2022/|title=Hansen stars as impressive Ireland power to bonus-point win over Wales|date=5 February 2022|work=The42|access-date=6 February 2022}} and in their 30–24 defeat away to France on 12 February, though he left the field with a head injury shortly after coming on.{{cite news|url=https://www.the42.ie/ireland-france-six-nations-2022-5681531-Feb2022/|title=Farrell's Ireland go down fighting as France's Grand Slam bid stays on track|date=12 February 2022|work=The42|access-date=12 February 2022}} With regular captain Johnny Sexton on the bench and vice-captain James Ryan injured, O'Mahony captained Ireland in their 57–6 home win against Italy on 27 February,{{cite news|url=https://www.the42.ie/ireland-italy-six-nations-2022-5695627-Feb2022/|title=Ireland rack up 57 points after red card forces Italy down to 13 players|date=27 February 2022|work=The42|access-date=27 February 2022}} and he retained his place in the starting XV in the 32–15 away win against England on 12 March,{{cite news|url=https://www.the42.ie/ireland-england-six-nations-2022-2-5709150-Mar2022/|title=Ireland finish over the top of 14-man England with bonus-point win in London|date=12 March 2022|work=The42|access-date=13 March 2022}} before being used as a replacement again in the 26–5 home win against Scotland on 19 March that secured the Triple Crown for Ireland.{{cite news|url=https://www.the42.ie/ireland-scotland-six-nations-2022-2-5715554-Mar2022/|title=Ireland claim Triple Crown by beating Scots as all eyes now turn towards Paris|date=19 March 2022|work=The42|access-date=19 March 2022}}

O'Mahony was selected in the squad for the 2022 Ireland rugby union tour of New Zealand,{{cite news|url=https://www.munsterrugby.ie/2022/06/14/andy-farrell-names-40-player-squad-for-new-zealand-tour/#post|title=Andy Farrell Names 40-Player Squad For New Zealand Tour|date=14 June 2022|work=Munster Rugby|access-date=17 June 2022}} and started in the 42–19 defeat against New Zealand in the first test on 2 July.{{cite news|url=https://www.the42.ie/ireland-new-zealand-11-5805859-Jul2022/|title=Disaster for Ireland as All Blacks score six tries to win opening test of the series|date=2 July 2022|work=The42|access-date=6 July 2022}} O'Mahony also started in Ireland's historic 23–12 win in the second test on 9 July, in what was Ireland's first ever away win against New Zealand,{{cite news|url=https://www.the42.ie/ireland-new-zealand-19-5812298-Jul2022/|title=Magnificent Ireland create magic and history with stunning win over the All Blacks|date=9 July 2022|work=The42|access-date=9 July 2022}} and in the 32–22 third test win against New Zealand on 16 July that secured Ireland's historic first ever series win in New Zealand.{{cite news|url=https://www.the42.ie/ireland-new-zealand-draft-5818559-Jul2022/|title=Ireland stun the All Blacks to become just the fifth touring side to win series in New Zealand|date=16 July 2022|work=The42|access-date=16 July 2022}}

During the 2022 Autumn Nations Series, O'Mahony started for Ireland in their 19–16 win against world champions South Africa on 5 November.{{cite news|url=https://www.the42.ie/ireland-south-africa-report-2-5911788-Nov2022/|title=Farrell's Ireland down the world champion Boks on a magic night in Dublin|date=5 November 2022|work=The42|access-date=5 November 2022}} Following a pre-match injury to regular captain Johnny Sexton, O'Mahony captained Ireland in their 13–10 win against Australia on 19 November.{{cite news|url=https://www.the42.ie/ireland-australia-report-2022-5924544-Nov2022/|title=Byrne's late penalty sees Ireland scrape past Wallabies in Dublin|date=19 November 2022|work=The42|access-date=19 November 2022}}

O'Mahony continued to start for Ireland in their opening fixture of the 2023 Six Nations Championship against Wales on 4 February, being replaced by Leinster's Jack Conan during the second-half of Ireland's 34–10 away win,{{cite news|url=https://www.the42.ie/ireland-wales-report-2023-5987543-Feb2023/|title=Farrell's Ireland get Six Nations tilt rolling with bonus-point win in Cardiff|date=4 February 2023|work=The42|access-date=4 February 2023}} before also starting in the 32–19 win against France in round two on 11 February.{{cite news|url=https://www.the42.ie/ireland-france-match-report-5993036-Feb2023/|title=Sublime Ireland notch bonus-point win after Six Nations epic against France|date=11 February 2023|work=The42|access-date=12 February 2023}} O'Mahony featured as a replacement in Ireland's 34–20 away win against Italy in round three on 25 February,{{cite news|url=https://www.the42.ie/ireland-italy-report-3-6004387-Feb2023/|title=Ireland's Grand Slam bid rolls on with bonus-point win over exciting Italy|date=25 February 2023|work=The42|access-date=25 February 2023}} before returning to the starting XV for the 22–7 away win against Scotland on 12 March{{cite news|url=https://www.the42.ie/ireland-scotland-report-2023-6017150-Mar2023/|title=Injury-hit Ireland beat Scotland to bring Grand Slam bid back to Dublin|date=12 March 2023|work=The42|access-date=12 March 2023}} and the 29–16 home win against England on 18 March, the latter of which secured the grand slam for Ireland.{{cite news|url=https://www.the42.ie/ireland-england-grand-slam-2-6022788-Mar2023/|title=Ireland finish over the top of England to claim glorious Grand Slam|date=18 March 2023|work=The42|access-date=18 March 2023}} O'Mahony was one of ten Ireland players selected in the 2023 Six Nations Team of the Championship.{{cite news|url=https://www.irishrugby.ie/2023/03/29/ten-irish-players-named-in-guinness-six-nations-team-of-the-championship/|title=Ten Irish Players Named In Guinness Six Nations Team Of The Championship|date=29 March 2023|work=Irish Rugby|access-date=29 March 2023}}

During the 2023 Rugby World Cup warm-up matches, O'Mahony started for Ireland in their 29–10 win against England on 19 August{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41208418.html|title=Keith Earls marks century with a try as Ireland power past England|date=19 August 2023|work=Irish Examiner|access-date=10 September 2023}} and featured as a replacement in their 17–13 against Samoa on 26 August{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41213431.html|title=Disjointed Ireland scrape past Samoa but injury fears for Cian Healy|date=26 August 2023|work=Irish Examiner|access-date=10 September 2023}} before being selected in Ireland's 33-man squad for the 2023 Rugby World Cup.{{cite news|url=https://www.irishrugby.ie/2023/08/27/farrell-names-33-player-ireland-rugby-world-cup-squad/|title=Farrell Names 33-Player Ireland Rugby World Cup Squad|date=27 August 2023|work=Irish Rugby|access-date=27 August 2023}} He started in Ireland's opening fixture of the tournament against Romania on 9 September, scoring two tries and earning the player of the match award in their 82–8 win,{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41222923.html|title=Farrell's Ireland breeze to comfortable win over Romania in World Cup opener|date=10 September 2023|work=Irish Examiner|access-date=10 September 2023}} the 59–16 win against Tonga on 16 September,{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41228014.html|title=Sexton breaks record in show of strength from eight-try Ireland|date=16 September 2023|work=Irish Examiner|access-date=16 September 2023}} the 13–8 win against South Africa on 23 September,{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41233060.html|title=Steely Ireland hold nerve in a Paris classic to knock off the Boks|date=23 September 2023|work=Irish Examiner|access-date=24 September 2023}} the 36–14 win against Scotland on 7 October, in which O'Mahony made his 100th appearance for Ireland,{{cite news|url=https://www.munsterrugby.ie/2023/10/06/peter-omahony-to-become-latest-ireland-centurion/|title=Peter O'Mahony To Become Latest Ireland Centurion|date=6 October 2023|work=Munster Rugby|access-date=7 October 2023}}{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41241475.html|title='A selfless player that gives everything to his team-mates' - Farrell and Sexton heap praise on centurion O'Mahony|date=5 October 2023|work=Irish Examiner|access-date=7 October 2023}}{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41241766.html|title=Centurion O'Mahony inspired by fond memories of Axel|date=6 October 2023|work=Irish Examiner|access-date=7 October 2023}}{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41243110.html|title=Ruthless Ireland cruise into World Cup quarter-final|date=7 October 2023|work=Irish Examiner|access-date=7 October 2023}} and the 28–24 defeat against New Zealand in the quarter-finals on 14 October..{{cite news|url=https://www.irishexaminer.com/sport/rugby/arid-41248141.html|title=Heartbreak: Ireland come up agonisingly short once more as quarter-final hex continues|date=14 October 2023|work=Irish Examiner|access-date=14 October 2023}}

On 17 January 2024, it was announced that O'Mahony would be the new captain of Ireland for that year’s Six Nations Championship.{{cite news|url=https://m.independent.ie/sport/rugby/six-nations/peter-omahony-named-new-ireland-captain-despite-contract-dispute-as-six-nations-squad-is-revealed/a2141983555.html|title= Peter O’Mahony named new Ireland captain despite contract dispute as Six Nations squad is revealed|date=17 January 2024|work=Irish Independent|access-date=17 January 2024}} Ireland went on to win the tournament after achieving four wins. O'Mahony said in a post-match interview amid speculation of his international retirement, "If it was my last one, it wasn't a bad one to go out on," he said. "I can hang the jersey in a good place, if it was."{{cite web |last1=Gault |first1=Matt |title=Six Nations 2024: 'Fuelled by nerves and tears, Peter O'Mahony inspires Ireland in possible swansong' |url=https://www.bbc.co.uk/sport/rugby-union/68589104 |publisher=BBC |access-date=17 March 2024}} He did not retire but in October 2024, but relinquished the captaincy to Caelan Doris.{{cite web |title=Doris aims to put World Cup lessons into action |url=https://www.bbc.co.uk/sport/rugby-union/articles/czr7yrjp5j7o#:~:text=Doris%20was%20appointed%20Ireland%20captain,over%20South%20Africa%20in%20Durban. |publisher=BBC Sport |access-date=10 February 2025}}

In February 2025, he made his first appearance in the 2025 Six Nations starting in a 32–18 away victory over Scotland. After the game, he recalled being booed off the pitch by Scottish fans as being "one of the biggest compliments" of his career.{{cite web |last1=Gallan |first1=Daniel |title=Scotland 16-32 Ireland: Six Nations 2025 – as it happened |url=https://www.theguardian.com/sport/live/2025/feb/09/scotland-v-ireland-six-nations-2025-live?page=with%3Ablock-67a5de358f081343aa1544df&filterKeyEvents=false#liveblog-navigation |publisher=The Guardian |access-date=10 February 2025}}{{cite web |title=O'Mahony thanks Murrayfield for 'complimentary' boos |url=https://www.bbc.co.uk/sport/rugby-union/articles/c1km10mlk4po |publisher=BBC Sport |access-date=10 February 2025}} Later that month, he announced he would be retiring from international duty alongside teammates Conor Murray and Cian Healy following the end of the tournament.{{cite web |last1=Elliot |first1=Ed |title=Key Ireland trio to retire after Six Nations in end of an era |url=https://www.independent.co.uk/sport/rugby/rugby-union/ireland-retirements-cian-healy-peter-omahony-conor-murray-six-nations-b2705869.html |publisher=The Independent |access-date=28 February 2025}} In his final game for Ireland, he came off the bench during a 22–17 victory over Italy in the final round of the tournament.{{cite web |last1=McLaughlin |first1=Luke |title=Dan Sheehan’s hat-trick sees off Italy and allows Ireland to celebrate legends |url=https://www.theguardian.com/sport/2025/mar/15/italy-ireland-six-nations-rugby-union-match-report |publisher=The Guardian |access-date=16 March 2025}}

In April 2017, O'Mahony was selected in Warren Gatland's 41-man squad for the 2017 British & Irish Lions tour to New Zealand.{{cite news|url=https://munsterrugby.ie/2017/04/19/murray-omahony-stander-secure-lions-selection/|title=Murray, O'Mahony & Stander Secure Lions Selection|date=19 April 2017|work=Munster Rugby|access-date=19 April 2017}} On 7 June 2017, O'Mahony made his non-test debut for the Lions when he came off the bench against the Blues in Eden Park.{{cite news|url=https://munsterrugby.ie/2017/06/05/stander-omahony-set-for-lions-debuts/|title=Stander & O'Mahony Set For Lions Debuts|date=5 June 2017|work=Munster Rugby|access-date=7 June 2017}}{{cite news|url=https://www.lionsrugby.com/report/west-strikes-late-blues-unlucky-lions/|title=West strikes late as Blues down unlucky Lions|date=7 June 2017|work=Lions Rugby|access-date=7 June 2017}} On 10 June, O'Mahony made his first start for the Lions, doing so in the match against the Crusaders in AMI Stadium.{{cite news|url=https://munsterrugby.ie/2017/06/08/lions-starts-for-murray-omahony/|title=Lions Starts For Murray & O'Mahony|date=8 June 2017|work=Munster Rugby|access-date=10 June 2017}}{{cite news|url=http://www.irishrugby.ie/news/39927.php#.WdyGt_iGPcs|title=Much-Improved Lions Lower Crusaders' Colours|date=10 June 2017|work=Irish Rugby|access-date=10 June 2017}} On 17 June, O'Mahony captained the Lions in their game against the Māori All Blacks in Rotorua International Stadium. In doing so, he became the first Munster player since Paul O'Connell in 2013 to captain a Lions team.{{cite news|url=https://munsterrugby.ie/2017/06/15/omahony-to-captain-the-lions/|title=O'Mahony To Captain The Lions|date=15 June 2017|work=Munster Rugby|access-date=15 June 2017}} O'Mahony played for 64 minutes, before being replaced by tour captain Sam Warburton, and led the side to a record 32–10 victory against the Māori.{{cite news|url=https://www.lionsrugby.com/report/lions-power-victory-maori-blacks/|title=Lions power to victory over the Māori All Blacks|date=17 June 2017|work=Lions Rugby|access-date=17 June 2017}} On 24 June, O'Mahony captained the Lions in their 30–15 first test defeat against New Zealand in Eden Park.{{cite news|url=https://munsterrugby.ie/2017/06/21/omahony-to-captain-lions-in-opening-test/|title=O'Mahony To Captain Lions In Opening Test|date=21 June 2017|work=Munster Rugby|access-date=22 June 2017}}{{cite news|url=https://www.lionsrugby.com/report/lions-slip-first-test-defeat-auckland/|title=Lions slip to first test defeat in Auckland|date=24 June 2017|work=Lions Rugby|access-date=24 June 2017}} He became the 11th Irishman to captain a British & Irish Lions test team and the first Cork Constitution player to do the same since Tom Kiernan in 1968.{{cite news|url=http://www.independent.ie/sport/rugby/lions-tour/peter-omahony-to-captain-lions-as-warren-gatland-names-team-for-first-test-35852837.html|title=Peter O'Mahony to captain Lions as Warren Gatland names team for first Test|date=21 June 2017|work=Irish Independent|access-date=22 June 2017}}{{cite news|url=http://munsterrugby.ie/2017/06/26/munstermen-in-action-across-the-world/|title=Munstermen In Action Across The World|date=26 June 2017|work=Munster Rugby|access-date=26 June 2017}} However, O'Mahony was dropped from the squad altogether for the second and third tests, with O'Mahony's former Ireland teammate Brian O'Driscoll, himself dropped by Gatland before the third Lions test in 2013, remarking that there "has to be someone to point the finger at in defeat".{{cite news|url=http://www.independent.ie/sport/rugby/lions-tour/omahony-unlucky-to-miss-out-in-tough-call-gatland-35880196.html|title=O'Mahony unlucky to miss out in tough call - Gatland|date=30 June 2017|work=Irish Independent|access-date=10 July 2017}}{{cite news|url=http://www.independent.ie/sport/rugby/lions-tour/comment-dropping-peter-omahony-highlights-how-warren-gatland-is-abandoning-his-most-successful-tactic-35877371.html|title=Dropping Peter O'Mahony highlights how Warren Gatland is abandoning his most successful tactic|date=29 June 2017|work=Irish Independent|access-date=10 July 2017}}{{cite news|url=http://www.independent.ie/sport/rugby/lions-tour/there-has-to-be-someone-to-point-the-finger-at-in-defeat-brian-odriscoll-on-peter-omahonys-lions-omission-35877754.html|title='There has to be someone to point the finger at in defeat' - Brian O'Driscoll on Peter O'Mahony's Lions omission|date=29 June 2017|work=Irish Independent|access-date=10 July 2017}}{{cite news|url=http://www.independent.ie/sport/rugby/lions-tour/alan-quinlan-the-irish-lions-did-us-proud-but-you-have-to-feel-for-peter-omahony-35911868.html|title=Alan Quinlan: The Irish Lions did us proud but you have to feel for Peter O'Mahony|date=10 July 2017|work=Irish Independent|access-date=10 July 2017}}

Correct as of 24 February 2025{{cite web |title=Peter O’Mahony |url=https://www.irishrugby.ie/player/peter-omahony/ |website=Irish Rugby |access-date=24 February 2025}}[http://en.espn.co.uk/statsguru/rugby/player/107693.html?class=1;template=results;type=player Peter O'Mahony], ESPN Scrum, 5 July 2017

* indicates inclusion of caps for British & Irish Lions

• Munster Schools Rugby Senior Cup:
• Winner (1): 2007

• All-Ireland Cup:
• Winner (1): 2009–10
• All-Ireland League:
• Winner (1): 2009–10

• United Rugby Championship:
• Winner (2): 2010–11, 2022–23

• Six Nations Championship:
• Winner (5): 2014, 2015, 2018, 2023, 2024
• Grand Slam:
• Winner (2): 2018, 2023
• Triple Crown:
• Winner (4): 2018, 2022, 2023, 2025

• British & Irish Lions tours:
• Tourist (1): 2017

• Munster Rugby Young Player of the Year:
• Winner (1): 2012
• Munster Rugby Men's Player of the Year:
• Winner (1): 2019

{{reflist|colwidth=30em}}

• [https://munsterrugby.ie/player?PlayGuid=PO196534 Munster Profile]
• [https://www.irishrugby.ie/player/peter-omahony/ Ireland Profile]
• [https://www.lionsrugby.com/players/peter-omahony/ British & Irish Lions Profile]
• [https://www.unitedrugby.com/clubs/munster/peter-omahony URC Profile]
• {{EPCR profile|PO196534}}
• [https://www.sixnationsrugby.com/player/?PlayGuid=PO196534&TeamId=1875 U20 Six Nations Profile]
• {{sport links}}

{{Munster Rugby squad}}

{{Navboxes

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{{British and Irish Lions team captains}}

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{{DEFAULTSORT:OMahony, Peter}}

Category:1989 births

Category:Living people

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