The brand consultancy said that H&M earned the accolade by delivering trend-setting apparel and couture to the mass market, through celebrity designers.
Other top performers in a 25-strong list of top brands, include the French-owned supermarket chain Carrefour, valued at £5.2bn; Sweden's Ikea at £5.2bn; the UK's Tesco, valued at £4.4bn; and Marks & Spencer, valued at £4.1bn.
The study concluded that the most successful brands understood the value of building and continuing to invest in their brands.
It found that more than half of the retailers in the top 25 generated more than 30% of their revenues from their own offshoot brands.
Other traits shared by successful retailers include the ability to expand internationally, which is helped by having a strong brand with cross-market appeal.
The flexibility to change store environments depending on store location and markets as well as "good corporate citizenship" were also mentioned as key factors.
Jez Frampton, the global chief executive of Interbrand, said: "Retail brands provide the most comprehensive opportunities for brands to truly come to life.
"The scope of retail brands goes from the insights that create a robust brand strategy, into store design, engagement of your people and in many cases, the creation and supply of own label produce."