| Year | Title | Role | Notes |
| 1995 | Alice in Russialand | Various Characters | TV film |
| 1996 | Mash and Peas | Fritz | Episode: "American Sitcoms" |
| 1998 | In the Red | Lawrence Boot-Heath | Mini-series; 2 episodes |
| Lenny Goes to Town | (unknown) | Episode: "Stoke on Trent" |
| 1999–2002, 2017 | The League of Gentlemen | Various Characters | Series 1–4; 22 episodes. Co-creator and co-writer |
| 1999 | The Comedy Trail: A Shaggy Dog Story | Tubbs Tattsyrup | TV Special |
| 2000 | Gormenghast | Professor Mule | Mini-series; Episode |
| Randall and Hopkirk (Deceased) | Sergeant Liddel | Episode: "Drop Dead" |
| 2002 | Legend of the Lost Tribe | Viking (voice) | TV film |
| Spheriks | Kaz (2002) (voice) | |
| 2004 | Blackpool | Adrian Marr | Mini-series; 6 episodes |
| Agatha Christie's Poirot | Dr. Bessner | Episode: "Death on the Nile" |
| Shameless | Eddie Jackson | 2 episodes: "Meet the Gallaghers" and "We're Going to the Moon" |
| 2005 | The Last Detective | Edward Netherton | Episode: "Friends Reunited" |
| Riot at the Rite | Critic | TV film |
| Under the Greenwood Tree | Mr. Shinar |
| 2006 | Hotel Babylon | Mr. Daniels | Episode |
| 2007 | The Bad Mother's Handbook | Leo Fairbrother | TV film |
| Kingdom | Jack Thriplow | Episode |
| The Old Curiosity Shop | Mr. Short | TV film |
| 2007–2015 | Benidorm | Mick Garvey | Regular; 43 episodes (Series 1–7) |
| 2008 | Agatha Christie's Marple | Henry Wake | Episode: "Murder is Easy" |
| Tim and Eric Awesome Show, Great Job! | Eric's Drums | Episode: "Jazz" |
| Doctor Who | Strackman Lux | 2 episodes: "Silence in the Library" and "Forest of the Dead" |
| 2009 | Minder | Vlad the Imposter | Episode: "A Matter of Life and Debt" |
| 2009–2011 | Psychoville | Various Characters | 14 episodes. Also co-writer |
| 2009–2013 | Whitechapel | Edward Buchan | 18 episodes. Writer of 2 episodes |
| 2010 | Terry Pratchett's Going Postal | Drumknott | Mini-series; 2 episodes |
| The First Men in the Moon | Sun | TV film |
| 2012 | Mr Stink | Sir Derek Dimble | TV film |
| Sport Relief 2012 | Mick Garvey | Episode: Benidorm meets Britain's Got Talent |
| 2012–2013 | Horrible Histories | Hollywood Producer | 3 episodes |
| 2013 | Heading Out | Jonathan Walters | Episode |
| Psychobitches | Dian Fossey | Mini-series; Episode |
| 2014 | Mapp & Lucia | Georgie Pillson | 3 episodes. Also writer |
| Happy Valley | Kevin Weatherill | 6 episodes |
| Toast of London | Francis Bacon | Episode: "Fool in Love" |
| 2014–2024 | Inside No. 9 | Various Characters | 53 episodes. Co-writer and director |
| 2015 | Lewis | Ian Tedman | 2 episodes: "One for Sorrow: Parts 1 and 2" |
| Professor Branestawm Returns | Professor Algebrain | TV film |
| 2016 | Camping | Robin | Mini-series; 6 episodes |
| Tracey Ullman's Show | Colin | Episode |
| 2017 | Midsomer Murders | Timothy Benson | Episode: "Red in Tooth & Claw" |
| 2018 | The Interrogation of Tony Martin | Tony Martin | TV film |
| The League of Gentlemen - Live Again! | Various Characters | TV Special |
| 2019 | Bounty Hunters | (unknown) | Episode |
| Britannia | Emperor Claudius | 2 episodes: "Imperial Visit" and "May the Gods Speak" |
| 2019–2021 | Worzel Gummidge | Mr. Braithwaite | 6 episodes |
| 2019, 2023 | Good Omens | Mr. Glozier | 2 episodes: "Hard Times" and "Nazi Zombie Flesheaters" |
