The sales spending spree is expected to continue as an estimated 21.5 million Britons head online for Cyber Monday bargains.
Experts predict it could even beat Black Friday to become Britain's biggest shopping day, as online retailers slash prices and continue deals for the culmination of the four-day pre-Christmas shopping event.
Cyber Monday has traditionally been a strictly 24-hour event, and online only - rather than in stores and online on Black Friday - but has evolved over recent years into a more extended period.
Britons were expected to spend £7.8 billion over the four-day period including Cyber Monday, up 7% on last year, according to predictions by VoucherCodes and the Centre for Retail Research (CRR).
Their figures suggest that Cyber Monday could overtake Black Friday by £7 million to become the biggest day for online and offline spending this year.
Britons were expected to spend £2.6 billion on Black Friday - an 8% increase overall on last year.
A number of big-name chains such as Amazon, John Lewis and Argos are continuing to offer bargains on Monday as part of the global sales bonanza.
The UK spends more money during the Black Friday to Cyber Monday event than in any other weekend of the year, new figures from the Financial Conduct Authority, based on a billion bank transactions, show.
A survey by PwC estimated that online was overtaking in-store shopping on Black Friday in every age group.
Even 60% of over-65s planned on chasing bargains online instead of in-store, with the under-25s doing just 25% in store.