Mortgage warning as Bank of England raises rates: Expert reveals costly mistake borrowers must avoid in 2027

A leading UK mortgage expert is warning borrowers against making an expensive mistake in 2027 by focusing solely on headline interest rates rather than the overall cost of their mortgage.

Sam Fox's advice comes after the Bank of England raised its base rate from 3.75% to 4% on 5 November, its first increase in more than three years, following a rise in inflation to 3.5%.

With further increases possible during 2027, homeowners could be forgiven for assuming mortgage costs are heading in one direction. However, the mortgage market is proving more complicated, with several major lenders cutting fixed-rate deals at the same time as the Bank announced its decision.

Property expert Sam Fox, founder of UK Mortgage Centre, said borrowers should first establish exactly what type of mortgage they have before reacting to the latest rate announcement.

"The first thing I ask anyone after a rate decision is what mortgage they're actually on.

"If you're on a fixed rate, nothing has changed for you today. If you're on a tracker, you'll feel it soon. And if you've ended up on your lender's standard variable rate, that's the one I'd look at sorting out first, because it's usually the most expensive place to be."

According to MoneySavingExpert, the latest 0.25 percentage point increase could add approximately £15 a month to repayments for every £100,000 borrowed on a tracker mortgage. Other variable-rate mortgages may also become more expensive, depending on individual lenders.

Fixed-rate mortgages work differently. Lenders typically price these deals using swap rates, which reflect market expectations for future interest rates rather than simply following the Bank of England's latest decision.

This helps explain why some major lenders were cutting fixed mortgage rates even as the base rate increased. At the time of the announcement, Barclays, Nationwide, Santander and Halifax were among the lenders reported to have reduced rates.

The best two- and five-year fixed deals were around 4.9%, although average rates were considerably higher, with Moneyfacts reporting typical two-year and five-year fixes of 5.96% and 5.99% respectively on 4 November.

Fox said: "People hear rates are up and assume every mortgage deal has gone up with them.

"It doesn't work like that with fixed rates. Lenders are looking at where they think rates will be over the next two or five years, not just what happened at one Bank of England meeting."

Two-year or five-year mortgage fix?

The outlook for mortgage rates remains uncertain. Market expectations following the November decision pointed to the possibility of another increase as early as February 2027, with rates potentially reaching around 4.75% by the end of that year.

Savills, meanwhile, forecasts Bank Rate at 4.25% by the end of 2027, with average mortgage rates remaining above 5% until early 2028.

The choice between a two-year and five-year fixed mortgage is therefore becoming increasingly important.

A five-year fix offers greater certainty over monthly payments, protecting borrowers against further increases. However, it also means committing to a deal for longer, potentially incurring early repayment charges if circumstances change.

A two-year fix offers an earlier opportunity to review the mortgage if rates fall, but leaves borrowers exposed to whatever market conditions prevail when the deal expires.

Fox said: "Nobody knows where rates will land, so be wary of anyone who says they do.

"A five-year fix means you know your payment whatever happens, but you're tied in for longer and early repayment charges can hurt if you move.

"With a two-year deal, you get an earlier chance to review things if rates come down, but you might be remortgaging into a tougher market. It comes down to how long you're staying and how much a jump in payments would stretch you."

Mortgage fees can make a cheap deal expensive

Borrowers are also being urged to consider arrangement fees and the overall cost of a mortgage rather than choosing a deal simply because it advertises the lowest interest rate.

A mortgage with an attractive rate but a substantial arrangement fee may ultimately cost more than a slightly higher-rate product with no fee.

Homeowners approaching the end of a fixed-rate deal should also compare their existing lender's product transfer offer with mortgages available elsewhere.

Around 800,000 fixed-rate mortgage deals priced at 3% or below are due to expire each year until the end of 2027, according to figures reported by the BBC, leaving many households facing the prospect of higher monthly repayments.

Fox recommends starting the remortgage process around six months before the existing deal expires to allow sufficient time to assess the market.

House prices face further pressure

The mortgage outlook also has implications for the wider housing market.

Savills forecasts mainstream UK house prices will fall by a further 1.5% during 2027, with the prolonged conflict in the Middle East contributing to higher borrowing costs and weaker buyer confidence.

However, the property consultancy expects a recovery from 2028, with first-time buyers potentially leading the improvement.

Improving deposit affordability, less stringent mortgage stress testing, more relaxed rules around high loan-to-value lending and the Government's Your First Home scheme are expected to provide support.

Fox said prospective buyers should remain cautious about taking on larger mortgages simply because lenders are prepared to offer them.

"Just because you can borrow more doesn't mean you should.

"Before anyone takes a high loan-to-value mortgage, I want them to know what the payment looks like if rates are still around here when the deal ends, and whether they can live with that.

"It's also worth understanding a lender's pricing bands, because putting down a little more deposit can sometimes unlock a noticeably better rate."

He added: "If your mortgage is coming to an end, don't leave it until the last minute. Start looking around six months beforehand. That gives you time to compare properly rather than drifting onto whatever your lender puts you on."