Penny Plain, the mail order womenswear retailer, is to invest£2 million to increase store numbers from seven to 20 in the next three years.
The 30-year-old company, which has 100,000 clients and a turnover of£5 million, said it would further expand if new shops are successful.
'We will be looking for interesting shopping locations off the main high streets, which we feel are attractive for our customers,' said chairwoman and founder Gillian Banyard.
The retailer also plans to tap into the male market with its first menswear range later this month.
The first two new stores will open in Amersham this weekend and at Gosforth in October.