LONDON, April 20 (Reuters) - British online fashion retailer ASOS (ASOS.L) expects full-year profit to meet market expectations after annual sales rose a third and said the new year had started well, helped by continued growth overseas.

www.asos.com

The firm, which targets Internet-savvy 18-34 year olds looking to emulate the designer looks of celebrities like Kate Moss, Sienna Miller and Alexa Chung, but at a fraction of the price, on Tuesday 20 April said retail sales rose 38 percent to 206 million pounds ($330.5 million) in the year to the end of March and were up 56 percent in the 19 days to April 19.

ASOS added that it expected pretax profit for the year to March 31 2010 to be in line with market expectations.

Prior to the update analysts were forecasting a consensus pretax profit of 20.2 million pounds, according to Thomson Reuters I/B/E/S, up from 14.1 million pounds in the previous year.

"We are approaching this year with considerably more confidence. Demand for our spring and summer ranges have been very strong and the Internet continues to outperform the other retail channels," ASOS Chief Executive Nick Robertson said.

UK and international retail sales grew 23 and 101 percent respectively.

While many retailers have struggled, ASOS has defied the recession, benefiting from a young core customer base and the migration of retail spending from the high street to the Internet.

Shares in ASOS, which have risen by over a half over the last year, closed at 523 pence on Monday 19 April, valuing the business at 387 million pounds.

($1=.6233 Pound)

(Reporting by Rhys Jones; editing by Kate Holton)