| Year | Title | Role | Notes |
| 1996–1998 | Hetty Wainthropp Investigates | Geoffrey Shawcross | 27 episodes |
| 1997 | Hostile Waters | Sasha | Television film |
| 2000 | This Is Personal: The Hunt for the Yorkshire Ripper | Jimmy Furey |
| Monsignor Renard | Etienne Pierre Rollinger | 3 episodes |
| 2004 | I Love the '90s | Himself | Commentator |
| 2004–2010 | Lost | Charlie Pace | 65 episodesScreen Actors Guild Award for Outstanding Performance by an Ensemble in a Drama SeriesNominated—Monte-Carlo Television Festival Award for Outstanding Actor – Drama SeriesNominated—Prism Award for Performance in a Drama SeriesNominated—Saturn Award for Best Supporting Actor on Television |
| 2005 | I Love the '90s: Part Deux | Himself | Commentator |
| 2008 | MADtv | Himself | 2 episodes |
| Caiga Quien Caiga | Episode: "#12.15" |
| 2009 | Chuck | Tyler Martin | Episode: "Chuck Versus the Third Dimension" |
| 2009–2010 | FlashForward | Dr. Simon Campos | 15 episodes |
| 2010 | Top Gear | Himself | 2 episodes |
| 2012 | The Unknown | Mark Nickel | 6 episodes |
| Children's Hospital | Dr. Owen Maestro | "British Hospital" |
| 2012–2016 | Wild Things with Dominic Monaghan | Himself | 30 episodesNominated—Canadian Screen Award for Best Science or Nature Documentary Program/SeriesNominated—Critics' Choice Television Award for Best Reality SeriesNominated—OFTA Award for Best Host or Panelist in a Non-Fiction ProgramNominated—Primetime Emmy Award for Outstanding Unstructured Reality Program |
| 2013 | Ridiculousness | "Dominic Monaghan" |
| The Eric Andre Show | "Krysten Ritter/Dominic Monaghan" |
| 2015 | 100 Code | Tommy Conley | 12 episodes |
| 2017 | Sofia the First | Fig | Voice; "The Crown of Blossoms" |
| A Midsummer's Nightmare | Mike Puck | Television film |
| 2018 | Bite Club | Senior Constable Stephen Langley | Premiered 15 August, Nine Network, Australia |
| 2022 | The Legend of Vox Machina | Archibald Desnay | Voice; 3 episodes |
| Moonhaven | Paul Serno | TV show |
| 2024 | Angry Birds Mystery Island | Hamylton | Voice; 16 episodes |
| 2025–present | The Librarians: The Next Chapter | Merlin | Guest (season 1), recurring (season 2) |
| 2025 | Billy and Dom Eat the World | Himself | 8 episodes |
