Last night, none of the biggest mortgage lenders had yet announced its intention to pass on the base rate rise to borrowers, but analysts expect most home-loan providers to do so in full over the next week or so.

The fourth interest rate rise in a year means borrowers with the average mortgage will now be spending more than £80 extra on their monthly repayments.

Michael Coogan, the director-general of the Council of Mortgage Lenders, warned borrowers to ensure their finances could cope with the extra strain. " Borrowers must expect rates to remain at or around their current levels for the foreseeable future and plan their finances on that basis," he said.

Peter Tutton, a policy adviser at Citizen's Advice, said: "This interest rate rise will put added pressure on some homeowners - our evidence shows it only takes a very small change in people's circumstances to tip them from manageable credit commitments into serious debt."

Personal finance analysts also warned consumers to watch out for sharp practices from their lenders. After each of the last three rate rises, a handful of banks and building societies passed on increases in full to borrowers, but failed to give savers an equivalent increase in their interest rates.

Andrew Hagger, a spokesman for Moneyfacts, the personal finance data analyst, said: "It has become common practice for savers not to necessarily gain to the same extent as borrowers lose out following an interest-rate increase - customers need to be aware of this risk and monitor rates closely."

Anti-bank charge campaigners said the increase also gave leading banks less reason to complain about the campaign for compensation. While several banks have warned the cost of repaying unauthorised borrowing charges could jeopardise their ability to offer free current accounts, a report published earlier this year suggested an increase in the base rate to 5.5 per cent would add £1.5bn to the banking sector's profits in 2007.