Tesco and Sainsbury’s will open twice as many stores on Boxing Day, 2009 than they did on 26 December last year.
Opening hours will also be extended on Christmas Eve to allow customers to shop later.
Tesco will open 252 of its biggest stores, compared with 120 last year and just 10 in 2007.
Sainsbury’s is opening 94 supermarkets – last year it only opened its Scottish stores and a small number in England.
Asda said it would not open any stores on Boxing Day but Morrisons, which has not previously traded on the day after Christmas, said it had not yet decided whether to open any stores this year.
