Stylist's autumn special runs to 92 pages, compared to the title's average pagination of 52.
The issue will be distributed tonight (Tuesday) and tomorrow and will be published on glossy paper stock.
Its publication coincides with London Fashion Week, which begins on Thursday.
The covers feature UK designers – Henry Holland, Louise Golland, Matthew Williamson and Hannah Marshall.
Hugo Boss, Escada, G-Star, Mercedes Benz and Guerlain are advertising in the issue.
Stylist has used multiple covers before but this issue is its most ambitious.
The free weekly is published by ShortList Media and hit the streets of London and other cities last year amid a paid-for magazine market under pressure.
Stylist is the sister title of ShortList, the free men's weekly.