Lloyds TSB was last week forced to admit it underpaid interest to current-account customers this summer.

The bank claimed the glitch hit only a small number, but the problem will raise fears that savers are routinely underpaid because of errors in banks’ systems.

Customer Steve Clark noticed the error when he received interest of just 33p on his Classic Plus account in August compared with the £8 he should have earned.

The account offers gross interest of 4% on balances of up to £2,500 if you credit the account with at least £1,000 a month.

“This amount wasn’t going to stop me feeding the kids, but it’s the principle that they can’t calculate interest correctly, and I had to point it out to them,” Clark said.

Lloyds, the country’s biggest current-account provider, has since admitted some people were also underpaid in July, although it said all customers have been repaid.

Commentators urge consumers to check their statements. David Kuo at money site Fool.co.uk said: “This incident highlights the importance of checking entries in your bank statements regularly. While some errors can be easily identified, others, such as interest rate errors, can be harder to spot.”

Lloyds TSB said: “Due to an isolated systems issue, a tiny percentage of our current-account customers were underpaid interest for July and August. All customers have now been paid the interest they were due including any interest on the interest they missed out on.

“We apologise to customers for any inconvenience caused.”