Homeowners have been warned to be on their guard, after figures showed that almost 20 mortgage lenders had used the latest base rate rise to boost their profits.
Borrowers should be wary of disproportionately high increases in their mortgage rate, experts warned, after data from independent broker Savills Private Finance revealed that at least 19 lenders are now charging more interest than the last time the base rate was 4.75 per cent.
Following this month's quarter point rise in the Bank of England base rate, a string of lenders - including high street names such as Nationwide and NatWest - are now charging a standard variable rate (SVR) of as much as 0.30 per cent more than they were in July 2005.
Melanie Bien, an associate director of Savills, said: "Most lenders have now announced revised SVRs with effect from September 1 and what we're seeing is a continued widening of profit margins.
"We would like to see a fairer and more transparent attitude to product pricing with a clearer link to bank base."
The Co-operative Bank has upped its SVR by the most in the last year. It is now 6.64 per cent - 0.30 per cent higher than the 6.34 per cent it charged the last time the base rate was at 4.75 per cent.
Nationwide is also among the worst offenders, pushing its SVR 0.25 per cent higher to 6.24 per cent, while a host of others have upped their rates by 0.10 per cent.
Louise Cumming, head of mortgages at moneysupermarket.com, urged borrowers to beware of discounted products, as these are priced from lenders' SVRs.
The rates on trackers, however, are guaranteed to move in line with the base rate, while fixed rates are well suited to those who need the certainty that their mortgage repayments will not rise.
"Loyal borrowers stuck on SVRs, or those who have chosen 'discounted' products pegged against the SVR are the ones who pay," said Ms Cumming. n Savills Residential has revised its forecast for UK property market growth upwards again, to six per cent for 2006.
It said supply shortages would continue to put upward pressure on house prices.