| Norwegian Sky Cruise Ship7th Floor Atrium · International Waters | 2performances | 6videos | 2015–2016 |
| Norwegian Sky Cruise ShipHot Tub · International Waters | 2performances | 1video | 2015–2016 |
| Norwegian Sky Cruise ShipStardust Lounge · International Waters | 4performances | 20videos | 2015–2016 |
| NosturiHelsinki · Finland | 1performance | 1video | 2014 |
| Novarock FestivalNickelsdorf · Austria | 1performance | 0videos | 2015 |
| NürburgringNürburg · Germany | 1performance | 0videos | 2011 |
| NX NewcastleNewcastle upon Tyne · United Kingdom | 1performance | 0videos | 2025 |
| O Brian’s Event Centre, SaskatoonSaskatoon · Canada | 1performance | 0videos | 2018 |
| O’Brians Event Center, SaskatoonSaskatoon · Canada | 1performance | 0videos | 2016 |
| O’Connell’s, San DiegoSan Diego · United States | 1performance | 0videos | 2008 |
| O2 AcademySheffield · United Kingdom | 2performances | 6videos | 2018–2022 |
| O2 AcademyBristol · United Kingdom | 4performances | 23videos | 2013–2025 |
| O2 AcademyGlasgow · UK | 1performance | 4videos | 2026 |
| O2 AcademyBirmingham · United Kingdom | 2performances | 18videos | 2024–2025 |
| O2 AcademyLeeds · United Kingdom | 2performances | 7videos | 2022–2025 |
| O2 AcademyLiverpool · United Kingdom | 3performances | 28videos | 2018–2025 |
| O2 Academy 2Birmingham · United Kingdom | 1performance | 3videos | 2026 |
| O2 Academy 2Oxford · United Kingdom | 4performances | 6videos | 2018–2025 |
| O2 Academy GlasgowGlasgow · United Kingdom | 2performances | 38videos | 2013–2019 |
| O2 Academy LeicesterLeicester · United Kingdom | 3performances | 5videos | 2018–2023 |
| O2 Academy NewcastleNewcastle upon Tyne · United Kingdom | 4performances | 19videos | 2011–2019 |
| O2 ArenaLondon · United Kingdom | 2performances | 48videos | 2012–2014 |
| O2 City HallNewcastle · United Kingdom | 1performance | 10videos | 2025 |
| O2 GuildhallSouthampton · United Kingdom | 2performances | 13videos | 2022–2025 |
| O2 RitzManchester · United Kingdom | 0performances | 0videos | — |
| Occupied 12 BarLondon · United Kingdom | 1performance | 0videos | 2015 |
| OdyssudBlagnac · France | 1performance | 0videos | 2006 |
| Off Broadway, St LouisSt Louis · United States | 1performance | 1video | 2012 |
| Ogden Theater, DenverDenver · United States | 1performance | 5videos | 2015 |
| Old Fire StationBournemouth · United Kingdom | 1performance | 2videos | 2017 |
| Old National Center, IndianapolisIndianapolis · United States | 1performance | 1video | 2013 |
| Old No 7 BarBarnsley · United Kingdom | 1performance | 0videos | 2014 |
| Old Red HouseWorkington · United Kingdom | 1performance | 0videos | 2008 |
| Old Times Jazz BarWuxi · China | 1performance | 0videos | 2010 |
| Old Trinity Hall, AustinAustin · United States | 1performance | 0videos | 2015 |
| Olympia, MontréalMontréal · Canada | 1performance | 3videos | 2023 |
| Olympic Opening CeremonyLondon · United Kingdom | 1performance | 1video | 2012 |
| Olympic Opening Ceremony RehearsalLondon · United Kingdom | 2performances | 0videos | 2012 |
| Oma’s Teich FestivalGrossfehen · Germany | 1performance | 0videos | 2011 |
| OmearaLondon · United Kingdom | 1performance | 0videos | 2019 |
| Ommegang Brewery, CooperstownCooperstown · United States | 1performance | 0videos | 2014 |
| On Blackheath FestivalLondon · United Kingdom | 1performance | 0videos | 2014 |
| One Eyed Jack’s, New OrleansNew Orleans · United States | 1performance | 0videos | 2009 |
| One-Up RecordsAberdeen · United Kingdom | 1performance | 0videos | 2007 |
| OosterpoortGroningen · Netherlands | 1performance | 2videos | 2013 |
| Open Air FestivalSt Gallen · Switzerland | 1performance | 0videos | 2015 |
| Open Air Gampel FestivalGampel-Bratsch · Switzerland | 1performance | 0videos | 2014 |
| Open Air HeitereZofingen · Switzerland | 1performance | 0videos | 2017 |
| Open Air Theater, San DiegoSan Diego · United States | 1performance | 0videos | 2016 |
| Open Air TheatreScarborough · UK | 1performance | 9videos | 2026 |
| Open Flair FestivalEschwege · Germany | 4performances | 8videos | 2011–2026 |
| Oran MorGlasgow · United Kingdom | 2performances | 17videos | 2008–2015 |
| Oriental Theatre, DenverDenver · United States | 2performances | 2videos | 2026 |
| OrpheumGraz · Austria | 1performance | 4videos | 2016 |
| Orpheum Theatre, Los AngelesLos Angeles · United States | 1performance | 0videos | 2017 |
| Osheaga FestivalMontreal · Canada | 2performances | 4videos | 2010–2013 |
| Oslo HackneyHackney · United Kingdom | 1performance | 0videos | 2020 |
| OstwerkAugsburg · Germany | 1performance | 9videos | 2014 |
| Other VoicesDingle · Ireland | 1performance | 1video | 2011 |
| Ottakringer BrauereiVienna · Austria | 1performance | 0videos | 2024 |
| Ottawa BluesfestOttawa · Canada | 1performance | 0videos | 2013 |
| Outland Live, ColumbusColumbus · United States | 1performance | 5videos | 2012 |
| OutpostHanoi · Vietnam | 1performance | 0videos | 2024 |
| Outside Shepherd’s Bush EmpireLondon · United Kingdom | 1performance | 0videos | 2009 |
| Ovens Auditorium, CharlotteCharlotte · United States | 2performances | 1video | 2017 |
| Oxford and Cherwell Valley CollegeOxford · United Kingdom | 1performance | 0videos | 2008 |
| Oxford UnionOxford · United Kingdom | 1performance | 0videos | 2019 |
| Oxjam, Coolings BarExeter · United Kingdom | 1performance | 1video | 2009 |
| Oyster Bar, Wilkes-BarreWilkes-Barre · United States | 1performance | 4videos | 2019 |
| Pabst Theatre, MilwaukeeMilwaukee · United States | 2performances | 7videos | 2018–2023 |
| Padova HallPadova · Italy | 1performance | 9videos | 2024 |
| Palacio VistalegreMadrid · Spain | 1performance | 0videos | 2020 |
| Palais Theatre, MelbourneMelbourne · Australia | 1performance | 0videos | 2023 |
| PalladiumRiga · Latvia | 2performances | 1video | 2023–2025 |
| PalladiumCologne · Germany | 4performances | 15videos | 2016–2025 |
| Palm Door, AustinAustin · United States | 1performance | 0videos | 2018 |
| Palmer Center, SXSW, AustinAustin · United States | 1performance | 3videos | 2013 |
| PalomaNîmes · France | 1performance | 3videos | 2017 |
| Pan PiperParis · France | 1performance | 0videos | 2024 |
| Pantages Theatre, MinneapolisMinneapolis · United States | 1performance | 0videos | 2019 |
| Panthers, NewcastleNewcastle · Australia | 1performance | 0videos | 2013 |
| Paper Tiger, San AntonioSan Antonio · United States | 1performance | 4videos | 2018 |
| Pappy & Harriets, PioneertownPioneertown · United States | 1performance | 0videos | 2008 |
| ParadisoAmsterdam · Netherlands | 1performance | 2videos | 2011 |
| Paramount Theater, HuntingtonHuntington · United States | 1performance | 1video | 2012 |
| Paramount Theatre, SeattleSeattle · United States | 1performance | 0videos | 2017 |
| Parco PaveseIgea Marina · Italy | 1performance | 0videos | 2019 |
| Park Avenue CDsOrlando · United States | 4performances | 8videos | 2010–2018 |
| Park Prirode PapukVelika · Croatia | 1performance | 0videos | 2012 |
| ParkenGothenburg · Sweden | 1performance | 0videos | 2009 |
| ParkersKilmarnock · United Kingdom | 1performance | 0videos | 2006 |
| Parklife FestivalJohannesburg · South Africa | 1performance | 0videos | 2014 |
| Parr HallWarrington · United Kingdom | 2performances | 2videos | 2014–2016 |
| Paste Ruins at Newport Folk FestivalNewport · United States | 1performance | 3videos | 2013 |
| Paste Studio ATLAtlanta · United States | 2performances | 13videos | 2012–2019 |
| Paul’s HouseBromley · United Kingdom | 1performance | 0videos | 2009 |
| PavillionBath · United Kingdom | 0performances | 0videos | — |
| PavillionsPlymouth · United Kingdom | 1performance | 7videos | 2014 |
| Peak District National ParkPikehall · United Kingdom | 1performance | 0videos | 2009 |
| Pearl Street, NorthamptonNorthampton · United States | 1performance | 4videos | 2013 |