Christmas shoppers 'to spend £1.2bn on Panic Saturday'
£1.2bn is expected to be spent by UK shoppers on the last Saturday before Christmas, with researchers calling it "Panic Saturday".
Some 13m consumers will be shopping for gifts and groceries, said the Centre for Retail Research (CRR).
The CRR predicts in-store sales will reach £4.7bn over the five days before Christmas - a 21% increase on 2013.
Department stores can expect to double their takings this weekend, according to a payments processing company.
Commercial manager for John Lewis' Oxford Street branch, Clare Scantlebury said: "The key difference here is the later fall of Christmas so we know that strength in trade will continue right through to Christmas Eve."
Consumer analyst Sue Hayward said: "People are starting to get a little more money in their pockets. We are seeing things like petrol and food prices slightly down.
"It is important for the retailers that they entice people into spending this money rather than obviously paying off their mortgage which may be the sensible option."
UK retail sales rose at their fastest annual rate in more than 10 years in November, thanks to the effects of Black Friday, official figures show.
Sales rose 6.4% compared with November last year, the highest annual increase since May 2004, the Office for National Statistics (ONS) said.
However the 6.4% rise is compared with a period in 2013 that did not include Black Friday trading which fell in December that year.
'Break all records'
Britain's "Black Friday" shopping surge in late November saw retail sales grow at their fastest pace for nearly 27 years, figures from the bosses' group the CBI show.
The survey found 71% of firms reported sales volumes up on a year ago while 9% said they were down, giving a balance of 61% - the highest since January 1988.
Barry Williams, CBI distributive trades survey chairman, said: "Increasing disposable income from real wages growth, and falling fuel prices are giving retailers reasons for optimism but we'll need to see in the New Year whether the upbeat mood takes hold."
Joe Lynam, BBC News business correspondent
Included in this £1.2bn estimate from the CRR for "Panic Saturday" spending will be quite a bit of food and drink bought to sustain consumers over the holiday period.
But even excluding grocery spending, this festive season could break all records for Christmas shopping.
For the first time since 2008 we feel economically more secure. Record numbers are in work and unemployment is down to 6%.
On top of that, petrol and energy costs are falling thanks to a plummeting oil price and our supermarket bills seem to be shrinking too thanks to a price war between the grocers.
All in all, many of us may be feeling wealthier and we're set to reflect that feeling in what - and how much - we spend this month.
Alongside Christmas stockings, credit card bills might also be bulging soon.
"Panic Saturday" will be good for department stories, with outlets in the North of England predicted to benefit the most, according to data released by payment processing company Worldpay.
"Many of these 11th-hour shoppers will be breaking into a cold sweat at the thought of heading to the High Street on the busiest shopping day of the year and praying for someone to take the pain away," said the company's UK managing director, Dave Hobday.
"Panic Saturday" follows on from the busy online shopping day of Cyber Monday, and the large discounts offered on Black Friday - a shopping phenomenon which originated in the US.
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