The end of fixed-rate mortgages has left more than a third of a million homeowners struggling to face a national bill of £1.02bn, it has emerged.

Research from Mortgage Monitor suggests that many of the 340,000 consumers who took out deals fixed for five years in 2003 are now struggling with their monthly repayments.

Many monthly repayments have increased by more than 35%.

One in five (23%) mortgage holders have become more anxious about keeping up with repayments, according to statistics, while one in 20 (5%) of the 70,000 on fixed rates admitted that they had no idea how they would meet the increases when their current rate expires.

The survey also found 14% suffered insomnia due to worries over their home loan and 17% reported arguments with their partners over repayments.

Mortgage holders questioned said they did not know where to go in order to find the best deal for re-mortgaging their property.

The FSA has launched a £2m advertising campaign to help the 1.4 million homeowners on fixed-rate deals which end this year.

Responding to the research, Mortgage Monitor chairman Les Jacobs, said: "The massive bill that homeowners face makes it more important than ever that they can find impartial advice and guidance to help them navigate the mortgage market. For many, finding the right deal will make the difference between making ends meet or facing financial strain or even repossession.

"Mortgage brokers do an important job, but too many of them are wedded to particular lenders, so they won't check the whole market for you. They also tend to provide advice 'there and then', rather than keeping clients updated about the suitability of their deal or contacting them when the time is right to switch."

The figures were based on a typical fixed-rate borrower who paid the average price for a UK home in 2003 and put down an initial 5% deposit on a 25-year term repayment mortgage.

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