Up to 800,000 borrowers on standard variable rates could save an average of more than £2,300 a year by switching to a new deal, analysis by Comparethemarket has found.

The website’s research suggests that these borrowers are paying nearly £200 a month over the odds.

Its calculations use the Bank of England’s lending figures from March when the average SVR was 4.09 per cent and the average two-year fixed rate was 1.42 per cent.

Based on the average outstanding mortgage debt per household of £136,273, a borrower’s annual costs would shrink from £7,896 to £5,580 by switching.

Collectively, the UK’s 11 million borrowers could save £2bn a year.

Comparethemarket director of money Mark Gordon says: “Languishing on a lender’s standard variable rate mortgage is likely to cost you thousands of pounds more than you need to pay.

“By remortgaging, the money could instead be put into savings or could be put away in preparation for any emergencies or to build up rainy day funds.

“While there are fewer mortgage products available on the market than usual at the moment, with the housing market slowly restarting again and physical property valuations able to take place once more, there are still plenty of good rates to choose from by looking around online.”