Shoppers spent an additional £1.9bn as they stockpiled on goods in the run up to the UK going into coronavirus lockdown, according to industry figures.
Market measurement company Nielsen's report found that supermarkets dealt with 79 million extra shopping trips in the month to Saturday, March 21. Boris Johnson announced a lockdown to contain coronavirus on March 23.
According to Nielsen, UK shoppers forked out an extra £1.9bn on shopping in the four weeks preceding the lockdown, while separate data supplied by Kantar Worldpanel shows March was the biggest month on record for supermarket grocery sales.
Homes spent an average of £63 more in the four weeks leading up to March 22, compared to what they would usually spend, Kantar's calculations say.
In the last week alone, Nielsen's figures show an 84% increase in frozen food sales, compared to the same week in 2019. Supermarket alcohol sales surged by 67%, with pubs and restaurants are closed to customers.
Kantar head of retail and consumer insight, Fraser McKevitt, said: "Retailers and their staff have been on the front line as households prepare for an extended stay at home, with grocery sales amounting to £10.8bn during the past four weeks alone - that's even higher than levels seen at Christmas, the busiest time of year under normal circumstances."
Sainsbury's saw the biggest growth in the past three months, out of the 'big four' supermarkets, which includes Morrisons, Tesco and Asda. Kantar says Sainsbury's sales were up 7.4%, while Tesco's rose by 5.5%, Asda's 4.9% and Morrisons' by 4.6%.