Paul Welsh is an American actor, improvisational comedian, and writer originally from New Fairfield, Connecticut, who later became active in the world of television and sketch comedy. He attended Georgetown University, where he studied political science and Italian, before embarking on a career in comedy and performance.

Welsh has performed extensively at the Upright Citizens Brigade (UCB), becoming a noteworthy member of the improv and sketch community by 2008, regularly appearing with the house improv team JV. His comedic talents have been featured in two solo shows—Men in Paintings and Paul Welsh Goes to a TED Conference—as well as in numerous performances across UCB stages on both coasts.

As an actor, Welsh is best known for his television roles, including portraying Trent Maddock on Crazy Ex-Girlfriend (2015–2018), and for playing the character Brad Portenburg in Brooklyn Nine-Nine (2013; guest appearance in Season 7 episode aired in 2020).

In addition to acting, Welsh has built a significant career as a writer and producer. He served as co-producer and executive story editor on Brooklyn Nine-Nine (2019–2021), during which he wrote or contributed to multiple episodes alongside his writing partner Madeline Walter, marking them as the first writing duo hired on the show. Following his work on Brooklyn Nine-Nine, Welsh co-wrote for the sitcom Killing It (2022) and penned the screenplay for the feature film Mack & Rita (2022).

Beyond television, Welsh continues to be engaged in the comedy and improv scene, both through performances and podcast appearances, such as sharing a story arc with Madeline Walter on an Earwolf podcast.