| Year | Award | Category | Nominated work | Result | Ref(s) |
| 2003 | Ian Charleson Awards | Commendation for the best classical stage performance in Britain by actor under age 30 | Three Sisters | Nominated | |
| 2015 | Saturn Awards | Best Actor on Television | Outlander | Nominated | |
| EWwy Awards | Best Supporting Actor in a Drama Series | Won | |
| 2016 | Golden Globe Awards | Best Supporting Actor – Series, Miniseries or Television Film | Nominated | |
| Satellite Awards | Best Television Ensemble | Won | |
| 2020 | Golden Globes Awards | Best Actor – Television Series Drama | The Crown | Nominated | |
| Critics' Choice Television Awards | Best Actor in a Drama Series | Nominated | |
| Screen Actors Guild Awards | Outstanding Performance by an Ensemble in a Drama Series | Won | |
| Satellite Awards | Best Actor in a Television Series – Drama | Won | |
| 2021 | Critics' Choice Television Awards | Best Supporting Actor in a Drama Series | Nominated | |
| Satellite Awards | Best Actor – Television Series Drama | Nominated | |
| Screen Actors Guild Awards | Outstanding Performance by an Ensemble in a Drama Series | Won | |
| British Academy Television Awards | Best Supporting Actor | Nominated | |
| Primetime Emmy Awards | Outstanding Supporting Actor in a Drama Series | Won | |
| 2024 | Drama Desk Awards | Outstanding Lead Performance in a Play | The Hunt | Nominated | |
| Drama League Awards | Distinguished Performance | Nominated | |