Retailers opened their doors for the second full day of the seasonal sales, as consumers' appetite for snapping up bargains showed little sign of abating.
Harrods expects 100,000 sale shoppers to pass through its doors
The first day of the Harrods sale started at 0900 GMT, with long queues reported outside the London store.
Top outlets and shopping centres across the country had reported robust post-Christmas trading on Wednesday.
The key winter sales season will be crucial for many retailers, after a lean performance by some in autumn.
Weak High Street sales figures in the latter part of the year had led analysts to predict the worst Christmas in 25 years.
Harrods said it expected to see 100,000 shoppers pass through the doors of its flagship Knightsbridge store on Thursday.
"People are gradually filtering in and up through the store," a spokesman for the company said. "We think it will be the busiest day of the year."
Harrods, which until recently started its winter sale in early January, said it expected demand to be particularly strong for women's clothing and shoes, jewellery and men's shirts.
First in line outside Harrods before the doors opened was 24-year-old Ria Yamagucki, who had been queuing since 0500 GMT.
"I'll have a look at the clothes but it's the designer accessories I'm after," she said.
Retailers know the next few days are crucial
Retail analysts Footfall reported that the number of shoppers visiting top stores across the UK on Tuesday was up 7% on last year.
Selfridges reported first-day sales 14% higher than a year ago, while the Trafford Centre near Manchester saw sales 3% up on last year.
Many thousands of bargain hunters were expected to descended on Kent's Bluewater and London's Brent Cross shopping centres on Wednesday, following heavy post-Christmas trading the previous day.
Business group the CBI said sales had been better than expected in the early run-up to Christmas.
However, experts warned that the current seasonal rush of activity may not translate into higher sales across the High Street, particularly with pressure from supermarkets and internet stores already leading to discounting.