One Day is a British romantic drama limited series based on the 2009 novel by David Nicholls as well as the 2011 film adaptation. It follows the 14-year relationship of Emma Morley and Dexter Mayhew, who meet at a graduation ball after graduating from the University of Edinburgh, and stars Ambika Mod and Leo Woodall in the lead roles.

Premiering on 8 February 2024 on Netflix, it received critical acclaim and was the most-watched series globally during the week of 12 February, with 9.9 million views.