* Company forecasts 90 percent annual sales rise
* Third increase to sales forecast
* Online retailers appear insulated from UK pressures (Adds details, background)
By Rahul B
Jan 11 (Reuters) - British online fashion group Boohoo.com Plc raised its full-year sales forecast for the third time after bucking a trend of slowing sales among British retailers.
Boohoo, which sells clothing, shoes and accessories online to a core market of 16-to-24 year-olds, said on Thursday it expects group sales to grow 90 percent for the year to February 2018 after revenue doubled in the four months to the end of December.
This is the third time the company has been able to increase its group sales forecast for the year after an initial forecast in April for a 50 percent rise. This was subsequently increased to 60 and then 80 percent.
The performance comes as Britons face pressure from slow wage growth compounded by higher inflation and appear to have cut back on almost everything other than food purchases in the run-up to Christmas.
It contrasts with the struggles of Marks & Spencer, one of the biggest names on the British high street, which on Thursday reported another fall in quarterly clothing sales.
However, retailers with strong online sales channels have seemed insulated from the broader downturn in consumer demand. Fashion company Ted Baker on Wednesday reported higher sales over Christmas as online purchases surged.
Boohoo, whose brands include PrettyLittleThing and Nasty Gal, has been winning market share from traditional retailers, benefiting from the increasing popularity of smartphone e-commerce and the extensive use of social media for promotion.
Boohoo group revenue doubled to 228.2 million pounds ($307.8 million) for the four months to the end of December thanks to stellar sales during Black Friday period.
Boohoo has been a star UK stock market performer, with its shares rising 460 percent over the last 24 months.
Shares in the company were flat at 207p at 1020 GMT, after having risen over 10 percent year-to-date. ($1 = 0.7414 pounds) (Reporting by Rahul B in Bengaluru; Editing by Bernard Orr and Keith Weir)