Nearly half of the UK's net users go to eBay monthly, and most of them are older surfers, according to net monitoring firm Nielsen/Netratings.
eBay continues to attract web users
About a fifth are considered heavy users, browsing on the online auction site for two hours or more per month.
The site seems to appeal most of all to those 35 and over, the figures showed. They make up 58% of the site's traffic.
The results show that eBay's popularity continues to rise, beating Google in the growth of visitors to the site.
The monitoring company reported that almost 11 million individual people visited eBay in July 2005, a 30% rise from July 2004.
Google still won over the most individuals hitting it, however, with 16m individual users visiting it in July.
Motors and fashion
"Everyone seems to be using eBay," said Alex Burmaster, European net analyst at Nielsen/Netratings.
"It isn't just the preserve of the young and web-literate. eBay is pretty much used by as many people over 50 as by those under 25."
Almost two out of every three of those coming up to retirement are using the web, compared with just a third in 2001, according a recent separate report.
The figures from Nielsen/Netratings show that the site's traffic also broadly reflects the gender demographics of the web as a whole.
Women reportedly accounted for 43% of eBay's UK visitors, compared to 48% of female web surfers in total.
The figures only reflected traffic to the websites from UK-based net surfers, and also excluded hits or visits from educational institutes.
"For many people eBay represents, more than any other brand, the greatest attributes about the internet, empowering and bringing people with complementary interests together," said Mr Burmaster.
TOP UK BRANDS BY HITS
Nielsen/Netratings: UK-based page views on sites
The analysts said that the auction site had also become a "habit" with many UK net users.
The report also showed that motors and fashion were the most popular sections of the auction house's site.
"Its Motors section is the most visited channel in the whole automotive sector," said Mr Burmaster.
"And it holds the top two most visited sites in the Nielsen/NetRatings home and fashion category, namely its clothing, shoes and accessories and home and garden sections."
The site is a draw for people looking for bargains on designer clothing, for example.
TOP UK BRANDS BY VISITORS
Nielsen/Netratings: UK-based unique visitors to the sites
"The site has a broad appeal which is probably responsible for attracting large numbers of first-time users to the e-commerce aspect of the internet, hopefully providing a positive knock-on effect for all companies operating in the realm of e-commerce," concluded Mr Burmaster.
EBay has recently had a large advertising campaign on UK TV, raising its visibility amongst net users in the country.
In another survey in April, web monitoring firm Envisional said that eBay was the top brand name on the net.
Slide and climb
But eBay has just started to climb out of a dip in fortunes. It was hit by a backlash in recent months which saw its shares slip, wiping $30bn off its market value.
It came under fire for raising charges for its sellers and failing to clamp down on misuse of the site.
In July, it attracted attention for refusing to act against sellers who put tickets for the Live 8 concern up for sale. It later banned the re-sale of tickets for the charity concerts.
It has since recovered, and recently raised its full year forecasts after unveiling a 53% jump in second quarter profits.
By the end of 2004, according to the Office of National Statistics, 52% of households in the UK had access to the net at home.
Almost 30% - about 8.1 million - of households and businesses now have broadband, but by the end of 2005, 99.6% of the UK will have access to broadband if they want it.