The BBC radio personality made the announcement on Friday’s Radio 2 Breakfast Show, on which he appears alongside host Zoe Ball.
Richie joins actor Will Mellor and former Coronation Street star Kym Marsh on the line-up for the upcoming 20th series of Strictly.
More stars will be officially announced for the show in the coming days.
The new series will see Tess Daly and Claudia Winkleman back on presenting duties, while Anton Du Beke is once again set to join Craig Revel Horwood, Motsi Mabuse and Shirley Ballas on the judging panel, following the recent departure of Strictly staple Bruno Tonioli.
Strictly Come Dancing returns to BBC One in the autumn.