Why are mortgage rates rising when the Bank of England hasn’t raised its rate?
Bank Rate can stand still while new fixed mortgage deals become more expensive. Here is why it happens, what it means for London borrowers and what to check before your next mortgage decision.
Fixed mortgage rates look ahead
Mortgage rates can rise without a Bank of England increase because lenders price new fixed deals using future interest-rate expectations and their own funding costs, rather than today’s Bank Rate alone. If markets expect rates to stay higher for longer, the cost of offering a fixed mortgage can increase before the Bank makes another decision.
For buyers and homeowners in Croydon, South London and across London, the important distinction is between the rate on a new deal and the rate already agreed on an existing mortgage.
Three reasons new fixed rates can change
Future rate expectations
A two-year or five-year fix covers a period of time. Swap rates are market rates used in managing interest-rate risk; they help inform fixed mortgage pricing and reflect expectations about future rates. They can move daily.
Funding and risk costs
Lenders use sources such as deposits and wholesale borrowing to fund mortgages. Funding spreads, credit risk, operating costs and capital requirements also influence the price offered to a borrower.
Competition and capacity
Lenders can adjust prices as they compete for business or manage demand. That means lenders may reprice at different times, and not every mortgage product moves in the same direction.
The Bank of England’s explanation of interest-rate transmission describes market reference rates, funding spreads and credit risk as factors in loan pricing. A swap rate is a pricing influence, not a mortgage quote available to a consumer.
How energy prices and the Budget can reach your mortgage
International events can affect a UK mortgage through their effect on energy costs, inflation and financial markets. In its September update, the Bank of England says disruption linked to the Middle East conflict has raised energy prices and increased the risk of more persistent inflation. That can change expectations for future interest rates, even while Bank Rate is unchanged.
Budget announcements can also influence markets if they change expectations about borrowing, inflation or economic growth. A Budget does not automatically make mortgages dearer or cheaper: the details and the market response matter.
For a household considering a purchase in Croydon or elsewhere in London, the useful question is how an available deal fits its budget—not whether a political headline predicts the next rate move.
Equally, today’s market rise does not establish where rates will be when your next deal begins.
Which borrowers are affected?
Already on a fixed rate
Your agreed mortgage rate normally stays the same until the fixed period ends. A lender increasing rates for new customers does not change that existing fixed rate.
On a tracker or variable rate
A Bank Rate tracker usually follows Bank Rate plus its contractual margin. A lender’s standard variable rate works differently and can change under the mortgage terms.
Buying or renewing a deal
The prices available for a new purchase, remortgage or product transfer may change. Compare the full cost of the options available for your circumstances.
What a rate change could mean in pounds
These calculations use a £300,000 capital repayment mortgage over 25 years. They compare hypothetical rates on the same balance and term; they are not current offers or forecasts.
| Annual interest rate | Monthly payment | Increase versus 4.00% |
|---|---|---|
| 4.00% | £1,584 | — |
| 4.50% | £1,668 | £84 |
| 5.00% | £1,754 | £170 |
Amounts are rounded to the nearest pound using a standard monthly repayment calculation. Rates are assumed constant solely for comparison. Actual lender calculations, fees and payment dates can differ.
Three South London situations
Croydon: a fix ending soon
A hypothetical homeowner’s fixed deal ends in four months. They can compare a product transfer with their current lender and a remortgage elsewhere, checking offer validity, fees and the date any early repayment charge ends.
Norbury: a first-time buyer
A hypothetical buyer sees a higher rate before submitting an application. They revisit monthly affordability, deposit and purchase costs before committing. An agreement in principle does not normally reserve a mortgage product rate.
Sutton: an existing fixed deal
A hypothetical homeowner has two years left on a fix. New market rates do not alter that agreed rate. Switching early would require a comparison of potential savings against early repayment charges and other costs.
Compare the cost and the fit
Start with your outstanding balance, remaining term, current rate and deal end date. Then compare monthly payments, product fees, any broker fees, legal or valuation costs and early repayment charges. Adding a fee to the mortgage can mean paying interest on it.
Think about flexibility too: a lower headline rate may be less suitable if you expect to move or need different overpayment terms. Extending the term can reduce monthly payments but increase total interest paid.
MoneyHelper’s remortgaging guidance suggests reviewing options up to six months before a deal ends. If payments are becoming difficult, contact your lender early to discuss support rather than waiting to miss a payment.
If you are looking for a mortgage broker in Croydon, or comparing mortgage options in South London or across London, a consultation can help you organise these questions around your own circumstances.
Mortgage rate FAQs
Why can fixed mortgage rates rise when Bank Rate stays the same?
Fixed mortgage pricing reflects expectations for interest rates over the fixed period, alongside lender funding costs, risk and competition. Those factors can change between Bank of England meetings.
Will rising rates change my existing fixed mortgage?
A market rise does not change the agreed rate on an existing fixed-rate mortgage during its fixed period. Your payment may change for other contractual reasons, and you will need to consider the rate that applies when the fix ends.
Does a Bank of England rate cut guarantee a cheaper fixed mortgage?
No. Lenders may already have priced in an expected cut. If markets expect fewer later cuts or other funding costs rise, new fixed mortgage rates can remain unchanged or increase.
Are tracker mortgages affected in the same way?
A Bank Rate tracker normally follows Bank Rate plus an agreed margin, subject to its terms and any minimum rate. New tracker products can have different margins. Standard variable rates are set by the lender and do not necessarily move in step with Bank Rate.
Should I choose a two-year fix, a five-year fix or a tracker?
There is no option that suits everyone. Compare payment certainty, how long you expect to stay, fees, early repayment charges and your ability to absorb higher payments. A tracker exposes you to rate increases; a longer fix can restrict flexibility.
How early should I review a mortgage that is ending?
MoneyHelper suggests reviewing options up to six months before your current deal ends. Check the new offer’s expiry date, completion requirements and any early repayment charge before arranging a switch.
Can I change to a cheaper rate after applying?
Sometimes a lender allows a product change before completion, but this depends on its rules, deadlines and available products. Ask whether fees, checks or a revised offer would be needed. A better future rate is not guaranteed.
Can a mortgage broker in Croydon help if I am buying elsewhere in London?
You can discuss a London purchase or remortgage with Gordon Blair through the booking link below. Explain the property location and your circumstances so the adviser can establish which options are suitable.
Is the initial consultation free?
The initial consultation offered on this page is free. Ask for confirmation of any later broker fees and when they become payable before proceeding. Lender and other third-party charges may also apply.
Understand your next mortgage move
Buying in Croydon, reviewing a South London mortgage or planning a move elsewhere in London? Talk through your budget, timing and mortgage options with Gordon Blair Financial Services.
Where the information comes from
- Bank of England: September 2026 rate decision and economic context — current context checked on 2 October 2026.
- Bank of England: August 2022 Monetary Policy Report, Box C — background explanation of how market rates and lender costs affect pricing; not used as current mortgage-rate data.
- MoneyHelper: remortgaging guidance .
- MoneyHelper: mortgage interest-rate options .