Aimed at 18- to 30-year-old women, the title presents itself as a practical fashion magazine, building on BBC2's What Not To Wear show. The show's presenters, Trinny Woodhall and Susannah Constantine, will be contributing editors.
The quarterly A5 magazine will launch on 26 May. It follows the success of the free What Not To Wear sampler that accompanied the BBC's other women's glossy, Eve, in December.
What To Wear will be published by the Eve team and edited by Lucy Dunn.
Jo Morrell, the publishing director of the BBC's Women's and Lifestyle group, said: "We've made a real mark on the market with Eve and building our women's portfolio to include a unique read for twentysomethings will take this to the next level."
Jane Brunton, the editor of Eve, added: "We're aiming to be the most trusted style adviser and fashion resource for women in the UK."