Retailers are hoping for a last-minute rush to the High Street on what is being predicted as the busiest shopping day of the year.
Visa Europe said it was expecting to process 26.5 million transactions, worth more than £1.2bn on Thursday.
Many customers have delayed shopping because of the bad weather. Experian said research indicated footfall on Monday to Wednesday was down 10-11%.
The upcoming rise in VAT may also tempt people to bring forward purchases.
VAT is due to rise from 17.5% to 20% on 4 January 2011.
Meanwhile, separate research from IMRG, which represents online retailers, suggests a record £153m will be spent online on Christmas Day.
Department store John Lewis said sales from Sunday to Wednesday were up 4.3% on the same period last year.
Its managing director, Andy Street, told the BBC's Today programme about the impact the weather had had on recent trading.
"Saturday was the worst day so far and some of our shops did have to close early on that day, but we have opened every shop every single day," he said.
And he admitted that online sales for the last few days would be "disappointing" after it took the decision on Saturday to close its online site three days early.
Independent retail analyst Rahul Sharma said that while many people were choosing not to buy online for fear of deliveries not making it in time, the High Street may not necessarily have been the main beneficiary of that.
"What would have benefited would have been enclosed malls, for example, where you can actually go in and spend the whole day shopping across a variety of stores," he said.
"The other beneficiary potentially is supermarkets where we are going for our regular grocery trip, we know they are going to be in stock and we can actually buy little Christmas treats and presents there."
'Twice as busy'
Selfridges, meanwhile, said it expected more than 250,000 customers to start their shopping on Christmas Eve, the majority of them men.
Supermarkets were also preparing for a record day.
"Stores and staff are fully prepared and stocked up for our busiest day of the year. We're expecting them to be twice as busy as a normal Saturday," said Tesco's Trevor Datsun.
Morrisons said it expected 5.15pm to be its busiest time of the year.