The online fashion retailer, which agreed to merge with Italian rival Yoox in March, swung to a pre-tax profit of £11m in the year to 31 March, from a £9.7m loss last year.
Sales rose by 22.8 per cent to £654m, the company reported yesterday, boosted by strong growth across all three websites, including Mr Porter and The Outnet, after investing nearly £14m last year.
The US and UK grew by 27 per cent and 24 per cent respectively.
Net-a-Porter was founded in 2000 by former fashion journalist Natalie Massenet. She pocketed an estimated £50m after selling a 97 per cent stake in the company to Group Richemont 10 years later.
The group changed hands again after agreeing to merge with Yoox in March, creating an industry giant with around €1.3bn (£940m) of sales.
Massenet, the group’s executive chairman, said: “In the last 15 years, the Net-a-Porter group has radically transformed the luxury market... It has been an incredible journey, beginning with a concept and turning that initial idea into the world’s premier online fashion destination.”