A day of flash sales known in America as "Black Friday" is crossing the pond and taking hold of British High Street staples such as John Lewis and Asda.
Some of the biggest names in retail will be slashing their prices, with plasma TVs and tablets expected to sell out in hours.
The US event traditionally takes place on the Friday following Thanksgiving and marks the beginning of the Christmas shopping season.
It will be followed by "Cyber Monday" where Amazon is hoping to top the 41 items it sold per second on Monday 3 December last year.
Amazon UK managing director Christopher North said: "Since we started Black Friday deals in the UK in 2010, the concept has really caught on and is now a much-anticipated event in the UK shopping calendar."
John Lewis are also joining in the fun - a spokesman said customers would be able to save up to 50% on selected small electrical and audio items tomorrow, up to £200 on selected large appliances and laptops and up to 25% on selected TVs.
In a first for Asda, it will mirror the flash sale extravaganza that has been held by parent company Walmart for the past decade.
Asda promised "earth-shattering savings" with deals on electronics, toys and gadgets through to everyday essentials such as batteries, describing Black Friday as "the most dramatic shopping event to ever hit British stores".