The web traffic analyst also revealed that the social network is the second most visited site by UK web users, after search engine Google. Hitwise revealed that between October and January 2008, one in every 42 web search contained the phase Facebook.
YouTube was the second most popular brand searched for by web users, but there were 52 percent more searches for the Facebook than for Google's video-sharing website. Online auction site eBay and social network Bebo were the next most popular brands searched for online.
Hitwise also revealed that during February this year, one in every 24 UK internet visits was to Facebook and traffic to the site has increased by 18.6 percent compared to the same period last year.
"The fact that Facebook is the most searched-for brand and the second most-visited site in the UK not only illustrates its success, but also the popularity of social networking in Britain," said Robin Goad, research director for Hitwise.
"Social networks now account for one in every 10 UK internet visits and one in every five page views. Only search engines receive more UK internet visits than social networks."
See also: Facebook gets Twitter-style status feeds