US online sales are set to hit a new record on this week's "Cyber Monday," Adobe Analytics said.

Internet purchases are expected to reach $9.4 billion, a jump of almost a fifth on last year's record-setting $7.9 billion take, according to an estimate from the company. 

Adobe measures transactions from 80 of the 100 largest US online retailers.

US merchants have long viewed the days after the Thursday Thanksgiving holiday as a prime time to part shoppers from their money, particularly during the "Black Friday" sales following the holiday.

This year's expected record-setting shopping comes as Price Waterhouse Cooper found for the first time that a majority of people surveyed said they would rather shop online than in a brick-and-mortar store.

Shoppers spent $7.4 billion online on Friday, according to Adobe. 

Some 40% of these purchases were made using smartphones. 

On Thanksgiving Day, US consumers spent $4.2 billion online.

Online sales on "Small Business Saturday" amounted to $3.6 billion, up 18% on last year.

This increase was "fueled by strong gains from both large and small retailers alike," said Vivek Pandya, lead analyst at Adobe.

"The weekend between Black Friday and Cyber Monday is emerging as a truly lucrative period for online commerce," he added.