More than half of the 18.5m people who accessed the internet from home or work in January visited MSN.co.uk or MSN.com, while just fewer than 50% visited Microsoft.com and its mail service, Passport.com.
The report, issued by internet audience monitor Jupiter MMXI, lists the 25 most popular websites according to how many unique visitors were received throughout January.
Microsoft occupies half the top 10 slots with Yahoo.com, in fourth place, being the first non-Microsoft site to appear, ahead of Freeserve.com at six, Google at seven and BBC.co.uk at eight. AskJeeves.co.uk came in at number 10.
The research showed that the success of classmate reintroduction service, Friendsreunited.co.uk continues. It had 20.5% of digital reach with 3.8m unique visitors in January.
Amazon.co.uk also had a good month, attracting 21.4% of the UK audience, while eBay.co.uk just managed to find a place in the top 25 with 13.2% of UK users visiting its site in January.
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