MoneySavingExpert founder Martin Lewis has warned that homeowners are "at risk from a ticking mortgage time bomb".
Lewis said next spring could see a "triple threat" to people with mortgages, if the Bank of England puts up its base rate to 5% or 6%.
This base rate is now 2.25% - but was just 0.1% a year ago. This is factored in to the price of new mortgages.
