As well as his appearance on the show, he is also well known for his children's books, as well as appearing in comedy shows such as Little Britain and Come Fly With Me. He also presented a one-off Christmas special of Blankety Blank and acts as the voice over for a clip show named Revenge of Alright on the Night. He also provided the voice of Pudsey in Pudsey the Dog: The Movie. He also provided the voice of The Voice Trumpets with Rochelle Humes when they joined the existing cast of Daniel Rigby, Antonia Thomas, Jim Broadbent, Fearne Cotton and Jane Horrocks in 2017, in the reboot of classic British children’s television series Teletubbies.
In 2020 Walliams performed a skit at the National Television Awards before he presented an award, wherein he appeared upon the BGT Stage and was dressed in different attire, before another version of David was sat at the Judges Desk and gave him a Golden Buzzer. In December 2020 he dressed up as the Queen as a part of the 'Britain's Got Talent Christmas Spectacular' and jokingly provided an alternative version of the Queen's Christmas speech, later in the show he led the Comedy Christmas Calendar Skit which featured several comedians who reached the Semi-Finals of the show between Series 7 & Series 14, and performed a dance routine with Stavros Flatley alongside Ashley Banjo. In Early June 2021 Walliams was a guest panellist upon an episode of ITV's 'The Masked Dancer UK'.
David is known for his wacky sense of humour and often for giving a chance to 'novelty' acts or acts that other Judges have found un-talented. Most of his Golden Buzzers have come from acts who would otherwise not have made it past the audition stage. However, David is also a fan of comedy and is one of the first Judges to give his opinion on comic acts.
- 2014: Christian Spiridon
- 2015: Lorraine Bowen
- 2016: Anne & Ian Marshall
- 2017: Kyle Tomlinson
- 2018: Donchez Dacres
- 2019: Flakefleet Primary
- 2019 (The Champions): Paddy and Nico
- 2020: Sign Along With Us