The 2021 NXT TakeOver: In Your House was the 35th NXT TakeOver, the 29th In Your House, and the second annual NXT In Your House professional wrestling pay-per-view and livestreaming event produced by WWE. It was held exclusively for wrestlers from the promotion's NXT brand division. The event took place on June 13, 2021, from the Capitol Wrestling Center, hosted at the WWE Performance Center in Orlando, Florida. It was the first In Your House to air on the livestreaming service Peacock, as well as the first to air on traditional PPV since St. Valentine's Day Massacre: In Your House that aired in February 1999; the previous TakeOver: In Your House only aired on the WWE Network. The TakeOver series was discontinued with NXT's rebranding to NXT 2.0 in September 2021, but In Your House continued on as NXT's annual June event. This was also the last In Your House event to air on PPV, as NXT's major events as of the 2022 calendar year no longer air on PPV.

Six matches were contested at the event including one dark match. In the main event, Karrion Kross defeated Kyle O'Reilly, Adam Cole, Johnny Gargano, and Pete Dunne in a fatal five-way match by technical submission to retain the NXT Championship. In the penultimate match, Raquel González defeated Ember Moon to retain the NXT Women's Championship. Other prominent matches included LA Knight defeating Cameron Grimes in a ladder match for the vacant Million Dollar Championship and in the opening bout, NXT North American Champion Bronson Reed and NXT Tag Team Champions MSK (Nash Carter and Wes Lee) defeated Legado del Fantasma (Santos Escobar, Joaquin Wilde, and Raúl Mendoza) in a Winner Takes All Six-man Tag Team match to retain both of their respective championships.