Edinburgh-based Atterley, founded by retail entrepreneur Mike Welch, secured the financial injection from PDS Multinational, a design house and clothing manufacturer dual-headquartered in London and Hong Kong.
Further details of the investment were not disclosed.
The funding round comes at a time of heightened investment activity in the online fashion sector, including fellow online platform Farfetch’s initial public offering of about $8 billion (£6.1bn) on the New York Stock Exchange last month.
Welch, who also founded tyre retailer Blackcircles.com, left the door open for a future possible float for Atterley, which follows a similar business model to Farfetch.
He said: “If there is a value precedent being set in the market then we wouldn’t rule out a float of our own, all options remain open to us and we own enough of our equity to determine our destiny.”
The Atterley site enables independent fashion boutiques and brands to list and sell their inventories, with more than 100 boutiques on its platform selling to some 80 countries.
It has recently launched image search artificial intelligence technology that allows online shoppers to search for items by uploading photos.
Welch said: “We are not going down the road of what I would describe as ‘spraying and praying’ with investors’ money, but we will be learning from those who have gone before and fully expect to prove our model in financial terms, sooner rather than later.
“We have spoken to a wide range of potential funders over the last six months, including private equity firms and industry players, but PDS really stood out in terms of the strategic fit, our vision for the business and the development of an Atterley own brand.”
PDS manages international supply chains and produces around one million garments daily for more than 200 brands and retailers worldwide, including Topshop, Zara, Jack Wills and Urban Outfitters.
It owns and operates manufacturing plants in Bangladesh, Sri Lanka and India and is set to report annual sales of just under £1bn in the current financial year.
PDS founder and chief executive Pallak Seth said: “This is a natural move for PDS as online becomes an increasingly important channel for our industry in providing insights into customer tastes and trends.
“It is important that PDS is able to develop insights from data and first-hand experience in online business will ensure we remain at the cutting edge of fashion and are able to provide market intelligence to our retail customers.”
Fashion sales in the UK are forecast to generate more than £18bn and account for almost a third of all online spending by 2020.