Research looking at the financial situation of 1,500 homebuyers found they believed they could afford repayments of around £780 a month.

However, the purchase of a £235,000 home with a 10% deposit would actually require payments of almost £1,300 a month.

Experian said should rates rise this figure would leap to £1,440, based on a standard variable rate of 5.5%.

The survey also highlighted a lack of knowledge of the Mortgage Market Review rules, which require banks to put mortgage applicants through more stringent affordability checks. The effect of the new regulations appear to have confused Help to Buy scheme borrowers as 43% believed the MMR would make it easier to obtain a mortgage with a small deposit.

In addition, 19% said the MMR would result in more relaxed lending criteria, highlighting a lack of consumer understanding of the new rules.

Only 15% of respondents knew they would have to speak with a qualified adviser before getting a mortgage.

Peter Turner, managing director of Experian Consumer Services, said: “It is somewhat concerning to see such gaps in first-time buyers’ awareness of long term affordability and the possible impact of interest rate increases.

“As the economy improves, interest rates will inevitably rise, and for first time buyers, who often have less discretionary income, they could well be hit the hardest. It is vital that people understand and take control of their financial situation now to ensure [their] dream home does not become a financial nightmare.”