Households who don’t change the way they spend, will have to fork out an extra £837 a year to pay for their food shopping, according to the data.

This is an increase from 17.1% in February, and covers the period of the four weeks to March 19th, according to Kantar.

The shop price annual inflation rate, as recorded by the British Retail Consortium (BRC) also showed a record high rise to 8.9% in March, up from 8.4% in February. This inflation level measures the price of 500 commonly bought items in the UK.

Shoppers are also changing the way they buy groceries. Households are going to the shops an average of four times a week in March, the highest amount since the start of the pandemic apart from at Christmas.

Shoppers buying more own-label products

Sales of own-label products were up 15.8% in the four weeks in March, according to Kantar, when compared to the same time last year, as shoppers look to save money.

Yet branded goods still made up 52% of sales, an increase of 7.2% in the last month, at the major supermarkets. This is the fastest monthly rise since February 2021, as recorded by Kantar.

Many retailers are also using loyalty schemes to retain shoppers and more than nine in 10 people have at least one loyalty card.

Despite the shortages of some fresh fruit and vegetables recently, the number of shopping baskets containing tomatoes, cucumbers or peppers in the 10 major grocers stayed at 17% in March, the same as February.

Sales of chocolate have also been rising, ahead of the Easter holidays, and are up 6% when compared to last year. Sales of hot cross buns have also risen by 5%.

Lidl is the fastest growing supermarket

Lidl’s sales rose by 25.8% in March, making it the fastest growing supermarket, and it had a market share of 7.4%. While Aldi had a market share of 9.9%, with a 25.4% rise in sales.

Sales at Morrisons rose by 0.1%, giving it a market share of 8.8%, while those at Waitrose rose 2.1%.

At Asda, sales rose 7.3%, slightly more than the rate of 6.9% at both Tesco and Sainsbury’s. Tesco is the biggest UK supermarket still, with a market share of 26.9%, followed by 14.8% at Sainsbury’s and 14.3% at Asda.

Shop price inflation has yet to peak

The data from the BRC shows record highs in food inflation but it says it has not peaked yet. Food inflation rose to 15%, up from 14.5% in February, according to its records, while fresh food inflation accelerated to 17.0%.

Helen Dickinson OBE, chief executive of the British Retail Consortium, said: “Shop price inflation has yet to peak. As Easter approaches, the rising cost of sugar coupled with high manufacturing costs left some customers with a sour taste, as price rises for chocolate, sweets and fizzy drinks increased in March.

“Food price rises will likely ease in the coming months, particularly as we enter the UK growing season, but wider inflation is expected to remain high. Retailers continue to work hard to keep prices, particularly of essentials, as low as possible by expanding value ranges and offering discounts for vulnerable groups.”

‘Supermarkets must ensure everyone has access to basic affordable food’

Sue Davies, Which? head of food policy, said: “Month after month we’ve seen a dramatic increase in food prices but our monthly supermarket price analysis shows that some supermarkets are much cheaper than others, so it’s unsurprising that people are choosing to shop where prices tend to be the lowest.

“Supermarkets must ensure everyone has access to basic affordable food with clear unit pricing to help shoppers to compare items and find the best value option for them. Budget ranges also need to be more widely available across stores, so consumers are not forced to pay over the odds to put healthy food on the table.”