The retailer will cut the prices of Christmas food, drinks, toys and gifts by half.
Tesco said the focus of the sale was firmly on gifts and essentials for Christmas.
Richard Brasher, Tesco's commercial director, said: "Customers are telling us that they are delaying their main Christmas purchases as they wait for bargains.
"Our Half Price Sale reassures customers that we're not making them wait. They've told us they still want to enjoy a special Christmas -- with big presents for their children and a proper Christmas meal -- but they want us to help make their money go further."
Some of the bargains include Delacoste champagne, down from £30 to £15 and beef roasting joints down from £8.48/kg to £4.48/kg.
Other retailers promoting various 50% off deals include Argos, Halfords, Boots, Comet, Currys and B&Q.
Both Marks & Spencer and Debenhams have also been holding 20% off sales in recent weeks.
The discounts come as rival retailer Woolworths begins a "closing down sale" after it failed to find a buyer.