The 19-year-old will spend the remainder of the 2022/23 campaign on loan with the Championship side who are currently just two points of the play-offs.
Delap scored three times in 22 appearances for the Potters and now switches to the Lancashire Club aiming to help their push for promotion.
The England under-19 international has made six appearances for City with his senior debut in September 2020, when he scored a superb goal in a 2-1 Carabao Cup third-round victory over Bournemouth.
Delap made his Premier League debut against Leicester in September 2020, before a Champions League appearance away to Sporting in February 2021.
He will now continue his development at Preston and everyone at City wishes him the best of luck for the rest of the season.
