The figures are due to be unveiled next Thursday by e-tailing trade body IMRG and come as parallel research by Hitwise shows that the online pre-Christmas rush will peak later this year than in 2005.
IMRG director of projects and marketing Andrew McClelland said: 'There has been increased competition this year in the online sector. A lot of retailers are sending out much larger catalogues to their customers to drive business to their web sites. This will have a big impact.
'Also, people who have traditionally used mail order will be trying out the web for the first time this year,' he added.
McClelland said that a key change in this year's Christmas trading would be 'people coming back to names they know from the high street from some other smaller online sites, as big retailers really increase their presence online this year'.
He added that the increased internet sales would not simply 'cannibalise' those from the high street and that 'increased online traffic will be in addition to traditional mail order business'.
In its pre-Christmas analysis report, Hitwise found that pre-Christmas shopping online would peak in the fortnight ending December 23 as opposed to December 10, as it did last year.
It added that, for the Christmas period, one in every 10 UK internet visits will go to a retail-related web site.
Despite McClelland's claims that traditional high street retailers will enjoy a stronger online showing this year, Hitwise's latest analysis of online trading in August suggested that companies such as eBay and Amazon will remain the strongest performers.
They took the top two places in a table of e-tailers, with eBay accounting for 25 per cent of overall site visits and Amazon achieving 6.3 per cent.
Hitwise also found that internet search engine Google and online community web site MySpace would be responsible for 25 per cent and 3 per cent of traffic to retail sites this Christmas respectively.