More than 380,000 homeowners switched to a new product last year to take advantage of current low mortgage rates.
Data from conveyancing firm LMS shows the total value of all remortgages was £65.7 billion in 2016 - 21% higher than the previous year.
The firm says enthusiasm to remortgage was driven by record low deals and an expectation that rates will rise in future. Its research suggests 32% of borrowers are expecting rates to rise in the next 12 months.
In 2016, the typical customer had been on their current deal for four years and 11 months compared to five years and one month previously.
The number of remortgages completed in November 2016 alone was 36,850 – the highest single monthly figure since July 2009. Across the year, a total of 384,950 remortgages took place, 15% higher than in 2015.
Some 89% of people were able to cut their monthly repayments by remortgaging their loan.
Andy Knee, chief executive of LMS, says: “Remortgaging was driven by record low rates throughout the year, enabling homeowners to make substantial savings to their monthly outgoings.
“We’re already witnessing surging where the last lender to raise rates experiences huge application volumes as buyers desperately try to take advantage of the lowest rates.
Ten year fixed term mortgages are also becoming increasingly popular as people seek longer-term security while the terms of Brexit continue to be thrashed out.”