Duopoly make up more than a quarter of UK internet time
Google and Facebook now account for one in every three and a half minutes of time Britons spend online - a finding the analysts behind the new data have used to lambast the UK's publishing sector for failing to effectively compete with the duopoly.
According to measurement firm Verto Analytics, UK adults accumulate 42.7 million days a month across Google properties - primarily search, YouTube and Gmail - the equivalent of more than one in every six minutes (17%) of UK internet time.
Around 11% of time (28.4 million days) is spent on Facebook-owned properties - including WhatsApp and Instagram.
This is followed by Microsoft at 7.2% (18.3 million days) and Apple at 5.5% (14 million days).
The 10 most dominant companies in the UK - all of which are US firms, except for the BBC - account for half of internet time.
Alongside the BBC, Sky is the only other UK company featured in the 20 most-heavily used sites in the UK.
"Google and Facebook’s share of internet time and ad revenue is staggering considering the internet’s near-infinite long tail," said Hannu Verkasalo, CEO of Verto Analytics.
"Estimates say they account for 50-75% of ad revenue but are hoovering up 80-99% of every new pound spent. Thus, their share of revenue is double their share of time. That’s because they’ve been highly innovative and make it much easier for advertisers to spend with them, such as providing both measurement tools and economies of scale.
"In contrast, the likes of the newspaper industry, who rejected a joint ad sales venture to combat declining revenues, aren’t offering advertisers the same path of least resistance and effectiveness. The erosion of newspapers, magazines and high street retailers plus the web giants' sway over political elections is just the beginning."
However, Vanessa Clifford, CEO of newspaper marketing body Newsworks, said it was no great surprise that Google and Facebook dominate the digital landscape when it comes to time spent online, but taking aim at newspapers was "peculiarly short-sighted."
"The vast majority of companies listed here are sharing and publishing content from external sources, including from the newsbrands that Hannu Verkasalo derides," Clifford said.
"Ignoring this overlap and claiming the 'erosion of newspapers' to the benefit of the digital giants may make for a less-complicated picture, but it fundamentally ignores a complex relationship."
Clifford added that, given the dominance of Google and Facebook, it is time both organisations adopted the same standards as publishers over the issue of accountable, third-party measurement - something Clifford describes as a "basic component of the media landscape which companies such as Facebook sorely lack".