A major computer error discovered in July that meant thousands of customers of Yorkshire and Clydesdale banks faced having to pay more for their mortgages has damaged customer confidence.
According to mortgagestrategy.co.uk, quoting Financial Ombudsman figures, Clydesdale bank had 410 mortgage-related complaints in the second half of 2010 compared to 66 from January 01 to June 30.
In July the bank revealed a rounding error occurred when a system was upgraded in 2005.
The calculation error combined with a unprecedented rapid reduction in interest rates, resulted in some customers' regular payments falling below the minimum required to complete the mortgage within the agreed term.
A total of 18,000 customers faced having to pay more than expected.
Clydesdale did however do better than Santander, which had the most mortgage-related complaints of 475 in the second six months of 2010.