| Year | Title | Role | Notes |
| 1986 | Austin | Dafydd | |
| 1987–1994 | Pobol y Cwm | Gareth Wyn Harries | |
| 1996 | Poldark | Jeremy Poldark | |
| 1998 | Hornblower: The Even Chance | Midshipman Horatio Hornblower | |
| Hornblower: The Examination for Lieutenant | Acting Lt. Horatio Hornblower | |
| 1999 | Warriors | Lt. John Feeley | |
| Hornblower: The Duchess and the Devil | Acting Lt. Horatio Hornblower | |
| Hornblower: The Frogs and the Lobsters | Lt. Horatio Hornblower | |
| Great Expectations | Pip | |
| 2002 | Hornblower: Mutiny | 3rd Lt. Horatio Hornblower | |
| Hornblower: Retribution | 3rd Lt. Horatio Hornblower | |
| Man and Boy | Harry Silver | |
| The Forsyte Saga | Phillip Bosinney | |
| 2003 | Hornblower: Loyalty | Commander Horatio Hornblower | |
| Hornblower: Duty | Commander Horatio Hornblower | |
| 2004 | Century City | Lukas Gold | |
| 2005 | Justice League Unlimited | Mister Miracle (voice) | Episode: "The Ties That Bind" |
| 2008 | The Meant to Be's | The Man | |
| 2010 | Ben 10: Alien Force | Devin Levin (voice) | Episode: "Vendetta" |
| Batman: The Brave and the Bold | Blue Beetle Scarab (voice) | Episode: "Revenge of the Reach!" |
| 2011–2012 | Ringer | Andrew Martin | |
| 2012 | Family Guy | Prince Charles (voice) | Episode: "Family Guy Viewer Mail " |
| The British | Narrator | |
| 2013 | Monday Mornings | Dr. Stewart Delaney | Guest role |
| Castle | Erik Vaughn | Episode: "The Squab and the Quail" |
| Necessary Roughness | Nolan Powers | Guest role |
| Glee | Paolo San Pablo | 2 episodes |
| 2014–2015 | Forever | Dr. Henry Morgan | Lead, 22 episodes |
| 2016 | UnReal | John Booth | Guest role |
| 2017–2020 | Liar | Andrew Earlham | Lead, 12 episodes |
| 2018–2021 | Harrow | Dr. Daniel Harrow | Lead role |
| 2022 | The Reunion | Thomas Degalais | Lead role |
| 2025 | Elsbeth | Angus Oliphant-Donnachaidh | Episode: "Tiny Town" |
