The data also found that a borrower with a £250,000 mortgage who locks into a 5-year fixed rate product and then decides to move or remortgage could face as much as £10,891 in early repayment charges (ERCs).
However, only 13% of borrowers see ERCs as being important to consider when getting their next mortgage.
Kevin Roberts, director of Legal & General Mortgage Club, said: “The crisis has taken its toll on the finances of people across the UK and many are now looking for ways to keep their household bills to a minimum.
“A great place to start is with a mortgage as this is normally people’s biggest monthly expense. So, reducing its interest rate down can only be a good thing, right?
“Well, our latest research shows why it is also important to look beyond the headline rate and consider other factors, like exit charges.
“Not doing so could mean having to pay thousands in unexpected costs when it comes time to move home or remortgage.
“When looking for a new mortgage, it is typically helpful to work with an independent adviser.
“Whether searching for a low-interest option, or a product which provides more repayment flexibility, it is worth seeking advice.
“Doing so will mean access to a larger range of mortgage options and these professionals can also recommend specific options based on your individual circumstances.”