Dhawan has appeared in a number of television shows in the United Kingdom. He had recurring roles in Weirdsister College, in which he played Azmat Madaridi, and series two and three of the children's TV series Out of Sight. He appeared in the mini series The Last Train (1999), and has guest starred in episodes on EastEnders, Altogether Now, and City Central. He also appeared in 2008 ITV drama, Wired, as Ben Chandrakar, alongside Jodie Whittaker and Laurence Fox. He was part of an ensemble cast on the NBC sitcom Outsourced, which aired during the 2010–11 season. In November 2013, Dhawan appeared as former Director Waris Hussein in An Adventure in Space and Time, a docu-drama created as part of the 50th Anniversary celebrations for Doctor Who. He also portrayed Paul Jatri, a 22-year-old man involved with a woman twice his age, in the first series of BBC One's Last Tango in Halifax. He played the part of Davos in the Netflix series Iron Fist. He starred as Sathnam Sanghera in the critically acclaimed The Boy With The Topknot, shown on BBC 2 in 2017.

For his performance in Bradford Riots he won the 2007 Royal Television Society Award for On-Screen Breakthrough.