Alex Jones and Amol Rajan will unveil the first three celebs on the BBC's magazine show on Wednesday, 4 August.
"Meet our first three celebrities, tonight 7pm," tweeted the official Strictly Twitter account.
— BBC Strictly ✨ (@bbcstrictly) August 4, 2021
Bosses have promised fans a full-length series this year but said the show will not be able to return to Blackpool due to the pandemic.
Covid restrictions saw the show cut short last year from 13 weeks to just nine, with the cast and crew quarantined in hotels. This led to the cancellation of both the highly popular Halloween Week and the annual trip to Blackpool's famous Tower Ballroom.
Executive producer Sarah James told The Mirror: “We’re so thrilled that Strictly will be returning for a full-length series this year, and know how much viewers are looking forward to getting their full Strictly fix and seeing the return of much-loved specials.”
She added: “We are all so sad that we won’t be able to get to Blackpool this year but can’t wait to be back dancing at the one and only Blackpool Tower Ballroom in the future."
Comedian Bill Bailey is the reigning Strictly champ, having won the Glitterball last year with Oti Mabuse, her second victory in a row.
There are four new professional dancers joining the show in 2021, with Anton Du Beke promoted to the judges' desk in place of Bruno Tonioli who is unable to travel to the UK for the show.
Joining the cast are World Junior Latin American Champion 2010 and former Dancing With The Stars Ireland professional Kai Widdrington; six-time Latin and Ballroom National Champion in Italy and former Let’s Dance Germany professional Nikita Kuzmin; reigning South African Latin Champion Cameron Lombard; and Polish Open Latin Champion 2014 and winner of BBC One’s The Greatest Dancer 2020 Jowita Przystal.
They join the professional dancers already revealed for the upcoming series Aljaž Škorjanec, Amy Dowden, Dianne Buswell, Giovanni Pernice, Gorka Marquez, Graziano Di Prima, Johannes Radebe, Karen Hauer, Katya Jones, Luba Mushtuk, Nadiya Bychkova, Nancy Xu, Neil Jones, and Oti Mabuse.
Strictly Come Dancing will air on the BBC later this year.
Watch: Anita Rani talks to Kate Thornton about taking part in Strictly