Kick-off at the Academy Stadium is set for 13:00 (UK) on Sunday 29 January.
Gareth Taylor's side were beaten finalists in last season's competition, being edged out by Chelsea in a thrilling encounter at Wembley Stadium.
And our ambition to go one better this time around begins against the Blades, who sit 11th in the Championship.
Sheffield United gained passage to the fourth round thanks to a 3-0 triumph over Nottingham Forest earlier this month.
We last faced the Blades in the quarter-finals of the Continental Cup in January 2020, running out 4-0 winners.
City have won the FA Cup three times - most recently in 2019/20 having also lifted the trophy in 2017 and 2019.
And you can watch the beginning of our latest pursuit of the trophy live with a CITY+ or Recast subscription.
CITY+ AND RECAST
You can watch exclusive City content on CITY+ and Recast.
Available for just £2.99 per month across all our digit platforms, a CITY+ subscription and provides supporters with unrivalled access to new and exclusive City content.
It will allow you to watch full-match replays of all Men's and Women's matches, selected broadcasts of Women's, Elite Development Squad and Academy matches and provides access to the full catalogue of City Studios documentaries.
The official Man City Recast channel offers fans flexible, pay-per-view live fixtures and on demand viewing options including match action from across the years, legend interviews, Best of Series, Man City Esports and City Studios documentaries.