Internet brands such as Amazon, Lastminute.com and Tesco Direct still have much to do if they are to gain the commitment of consumers, despite spending millions on advertising and marketing.
Branding consultancy Interbrand Interactive said companies which had set up on-line divisions under the assumption that brand loyalty would immediately follow should not rely on the strength of the parent brand.
Interbrand's research looked at the quality of awareness, knowledge, credibility, satisfaction, authority, personality and relevance of several internet brands.
Online books and music retailer Amazon rated the best, although its brand equity was lower than what would be expected for a real world company of its size.
Interbrand Interactive Jez Frampton said internet brands should be treated as new entrants to the market, even if they had the advantage of being linked to high street names.
He added that awareness of a brand did not guarantee commitment, and urged companies to focus on the long-term emotional attributes of the brand in marketing and advertising campaigns.
"Online brands lack the richness and complexity of their offline counterparts, and few long-term emotional bonds are being generated with consumers," he said.
"E-commerce businesses need to recognise that spend to secure brand awareness alone is no guarantee of enhanced sales. In an environment where high burn rate is a huge issue, effective marketing expenditure should be top of every business leader's list," he added.