Akhtar is known for the role of the clumsy Muslim extremist Faisal in Chris Morris's film Four Lions. Among his other comedic roles are Gupta in The Angelos Epithemiou Show, Maroush in The Dictator, and Smith in Joe Wright's film Pan.

Akhtar also gained recognition for dramatic roles: in 2015 he was nominated for a BAFTA for Best Supporting Actor for the role of Wilson Wilson in the Channel 4 series Utopia (2014). He played shopkeeper Ahmed alongside Toby Jones in the BBC miniseries Capital and Sergeant Ira King in the BBC series River. Reviewing River in The Daily Telegraph, Michael Hogan wrote: "This series was beautifully written by Abi Morgan, stylishly directed and, above all, superbly acted. The quieter, less showy supporting actors also shone. Not only the veterans [...] but also fresher faces: Adeel Akhtar as River's endlessly patient partner and Georgina Rich as his psychiatrist."

In 2016 Akhtar appeared as Shahzad in the one-off BBC drama Murdered by My Father. For this role he received the 2017 BAFTA for Best Actor, becoming the first non-white actor to receive this award. He also appeared as Rob Singhal in the acclaimed BBC miniseries based on John le Carré's novel The Night Manager.

In autumn 2016 Adeel became a patron of the Half Moon Theatre.