Retail researcher Conlumino is forecasting Black Friday will generate £1.6bn UK sales in store and online, up 20 percent on 2014.
Online spending is forecast to soar 32 per cent year-on-year to £1.1bn, according to Experian-IMRG.
Black Friday, the day after the US Thanksgiving holiday, was so named because a surge in spending would see retailers begin to turn a profit for the year.
The day has developed into an important part of the British shopping calendar in recent years, as retailers competed with bargains offered by Amazon.
But misgivings about the broader impact on crucial pre-Christmas trading are illustrated by the decision of supermarket group Asda, itself owned by US-based Wal-Mart, not to join the frenzy this year.
Other retailers are prepared to take the risk and sign up for an event that sparked brawls in stores last year. “The issue for retailers is in how they can benefit from this demand, while not losing margin, or damaging their reputations,” said Conlumino’s Maureen Hinton.
Though it delivered a sales boost in 2014, it lowered demand in the weeks before and after and created an expectation of continued pre-Christmas discounts.
Some retailers failed to cope with demand, which saw some websites crashing and delivery operations overloaded.