The consumer site said in over three quarters (78%) of cases borrowers were offered some form of assistance, but is calling on lenders “not to use the current financial crisis as an excuse to neglect struggling borrowers”.
The latest research from Which? also revealed that seven in 10 people (72%) are worried about mortgage rates while 14% of people are struggling with their repayments.
Which? claims just a third of people (36%) who are struggling with mortgage repayments have approached their lender for help.
Options available to lenders include moving customers from a repayment to interest-only mortgage, allowing them a payment holiday or allowing them to move to a different deal.
An increase of £50 a month in mortgage repayments would have an impact on three quarters of households, said the site.
Some 37% would need to cut back on regular spending, 20% would reduce the amount they are saving and 9% would not have enough for essentials.
Although the Bank of England Base Rate is not expected to rise in the near future, recent research by Which? Money shows that a fifth of lenders have increased the rates on their SVR mortgages since the rate reached its all-time low of 0.5% in March 2009.
Which? executive director, Richard Lloyd, said: "With ongoing uncertainty about the economy, it's not surprising that many people are worried about their household finances. For some it would only take a small increase in mortgage rates to send them over the edge.
"If you're struggling with mortgage repayments then your first port of call should be your lender. It's not in anyone's interest for people to default on their mortgage, so it's important that lenders do all they can to help their customers who are struggling with repayments."
