The 2021 English football summer transfer window runs from 24 May to 31 August 2021. Players without a club may be signed at any time, clubs may sign players on loan dependent on their league's regulations, and clubs may sign a goalkeeper on an emergency loan if they have no registered senior goalkeeper available. This list includes transfers featuring at least one club from either the Premier League or the EFL Championship that were completed after the end of the winter 2020–21 transfer window on 2 February and before the end of the 2021 summer window.
All players and clubs without a flag are English. Note that while Cardiff City, Swansea City and Newport County are affiliated with the Football Association of Wales and thus take the Welsh flag, they play in the Championship and League Two respectively, and so their transfers are included here.
The 2015–16 season was the 117th season of competitive league football in the history of English football club Wolverhampton Wanderers. The club are competing in the second tier of the English football system, the Football League Championship for a second consecutive year having finished 7th in the previous season following their promotion from League One.
The 2016–17 season was the 139th year in the history of English football club Wolverhampton Wanderers. The club competed in the second tier of the English football system, the Football League Championship for a third consecutive year.
The 2017–18 season was the 140th in the history of English football club Wolverhampton Wanderers and the first under former FC Porto manager Nuno Espírito Santo who was appointed on 31 May 2017. The club competed in the English Football League Championship for the fourth consecutive and final year as well as the EFL Cup and the FA Cup.
