One lucky homeowner has managed to save £2,100 a year by following mortgage advice from Martin Lewis 's MoneySavingExpert.
The mortgage tip is more important than ever as homeloan rates are slowly rising.
This is because the Bank of England (BoE) hiked interest rate for the fifth time in a row last week.
This rate is built in to the cost of mortgages.
Those on a tracker rate or standard variable rate (SVR) mortgage see their interest rates go up automatically in line with BoE rate hikes.
Existing fixed rate deals aren’t affected by base rate changes - though new fixed deals are.
However, lenders have slowly been pulling cheap deals in recent months in anticipation of more rate hikes.
The latest MoneySavingExpert email said that those on tracker or SVR homeloans will "soon see costs increase by roughly £12/month per £100,000 of mortgage debt".
It added that "today's cheapest fixes are three times higher than last October's".
But one MoneySavingExpert reader said they have managed to save £2,100 a year by taking out a deal with their existing lender.
Remortgaging with your current lender is known as a product transfer.
These deals can be cheaper than remortgaging with a new lender - though they might not be.
But taking a product transfer does often mean tough affordability checks taken out with new mortgages are scrapped.
The reader said: " Just went for a new deal with my existing provider at the end of a five-year fix, was able to save £175/month [£2,100/year] - same terms. I used the mortgage tool on MSE."
Martin Lewis had a list of quick tips for homeowners trying to find the best homeloan deal for them:
Ask for your current lender's deals
Lewis said: "[Product transfers] didn't used to be a great option, but these days, as your existing lender may forego affordability checks if you're not borrowing more, it can work out well. Plus there'll likely be less paperwork and lower fees."
Compare the best deals
Lewis said the MoneySavingExpert Mortgage Best Buys comparison helps show the best deals on the market.
One reader said: "We remortgaged in April and our monthly payment dropped from £900 to £750. Was our first remortgage as we bought our first house two years ago."
Compare offers to your current deal
Online mortgage calculators can help work out how much your repayments will be with different sorts of mortgage.
MoneySavingExpert has one, as does MoneyHelper, and most mortgage lenders have their own too.
Use a mortgage broker to make things easier
Lewis said: "Lenders do both credit and affordability checks (likely to be tougher to pass for some now due to the rising cost of living) that can kibosh applications. It's tough to know who'll accept you and how much you'll be able to borrow."
"Find a good mortgage broker and they'll have information on this that's very difficult for you to get yourself."
Many mortgage brokers also get access to secret deals you won't be able to get yourself by going direct to lenders, and will fight your corner if a lender gets difficult.