The data from the Office for National Statistics (ONS) defied economists’ forecasts, which had predicted the rate would climb to 4%.

A significant slowdown in the cost of food was the main factor behind the stability. Inflation for food and non-alcoholic drinks fell to 4.5% in the year to September, down from 5.1% in August, marking its slowest rate of increase in over a year.

Grant Fitzner, the ONS chief economist, noted that the overall cost of food and non-alcoholic drinks fell “for the first time since May last year,” though he cautioned that prices for items such as red meat and chocolate have continued to rise. For shoppers, this means that while prices are still going up, they are doing so more slowly.

The surprise figure, which is still well above the Bank of England’s 2% target, has shifted expectations for future interest rates. Luke Bartholomew, deputy chief economist at Aberdeen, called the news a “positive surprise for the Bank of England”, adding that “the UK’s inflation problem looks slightly less bad now than it did a few weeks ago”. While an interest rate cut in November is seen as unlikely, analysts believe the prospect of a reduction in December has now increased.

However, experts warned that many families are still struggling with the cumulative impact of past price rises. “On paper a flat inflation reading is to be welcomed. But in the real world, many families are still struggling to make ends meet,” said Kevin Brown, a savings specialist at Scottish Friendly. He noted that the Monetary Policy Committee will want to see clear evidence of inflation returning to its target before acting, which is a “blow for borrowers hoping for mortgage rates to come down further”.