[6] Walsh supported Stephen K. Amos on his 2008/09 Find the Funny and 2009/10 The Feelgood Factor tours,[1][2] as well as at the 2010 Reading and Leeds Festival.

Walsh was resident host at Komedia's Comic Boom in Brighton and has also been an 'audience wrangler' (a more recent version of the traditional warm-up comedian) for QI.

[13][14] Seann hosted Flinch, a physical gameshow for Netflix,[15] alongside Lloyd Griffith, and Desiree Burch.

[17] Walsh's relationship with actress Rebecca Humphries ended in October 2018 after a video and photos of him kissing his Strictly Come Dancing partner Katya Jones were published.

[18] In a now-viral tweet, Humphries stated that Walsh had called her “mental” and “psycho” for voicing her suspicions about his relationship with Jones in the weeks leading up to the incident.

[11] During an interview with Ellie Calnan, in March 2022, Walsh described how the incident was still "trauma" for him and how he underwent treatment for depression and anxiety, to help him cope with the fallout.