Islay Robinson examines the rise in UK inflation to 3.5% in September 2026, exploring what higher core and services inflation could mean for Bank of England policy, mortgage rates and borrowers ahead of the November decision.

UK consumer price inflation rose to 3.5% in the year to September 2026, up from 3.1% in August and above the 3.4% forecast. The Office for National Statistics (ONS) published the figures on 21 October, showing the highest annual rate since October 2025. For borrowers, the concern is not simply that inflation has risen, but what the underlying figures could mean for interest rates and mortgage pricing over the coming weeks.

Motor fuel was the main driver, with prices rising by 29.8% over the year. However, I am also looking closely at the measures beneath the headline. Core inflation rose to 2.8% from 2.6%, in line with forecasts, while services inflation increased to 3.7% from 3.4%. Goods inflation reached 3.2%, its highest level since September 2023, while food inflation remained at 1.3%.

The distinction matters because a rise driven mainly by fuel may prove temporary. Stronger core and services inflation can be more difficult for policymakers to dismiss, particularly if domestic price pressures persist. The latest figures do not determine what the Bank of England will do next, but they give the Monetary Policy Committee more to consider ahead of its November decision.

Why Does Services Inflation Matter for Mortgage Rates?

Services inflation is worth watching because it can reflect persistent domestic cost pressures, including wages and the costs businesses face when delivering services. It had fallen from 4.5% in March to 3.4% in August, according to the Bank of England's September Monetary Policy Committee minutes. September's increase to 3.7% reverses part of that progress.

There was already a difference of opinion within the Committee at its September meeting. Three of the nine members voted to increase Bank Rate from 3.75% to 4%, while the remaining six voted to hold it. Those favouring a rise were concerned about the possibility that higher energy and food costs could feed into wages and other prices.

The latest inflation figures may strengthen the arguments of members who favour a tighter policy, but they do not guarantee a rate increase. The Committee will also consider economic activity, employment, wage growth, energy prices and whether inflationary pressures are likely to persist.

How Could Higher Inflation Affect Mortgage Pricing?

Inflation data can influence mortgage pricing before the Bank of England announces a decision. Fixed-rate mortgages are priced partly by reference to swap rates, which reflect market expectations for future interest rates. When new data changes those expectations, swap rates can move and lenders may adjust the rates they offer.

The direction is not automatic. Lenders also consider their funding costs, competition, risk appetite and commercial priorities. A higher-than-expected inflation reading can put upward pressure on fixed mortgage rates, but the effect varies between lenders and products.

For borrowers, the important distinction is between the headline figure and the broader inflation picture. Motor fuel was the largest driver of September's increase, and that contribution could ease if fuel prices fall. However, core and services inflation also rose, making the latest release harder to explain solely as a temporary fuel effect.

I would not try to predict the next move in mortgage pricing from one release. I would, however, want clients with a purchase or refinancing in progress to understand how changes in pricing could affect their plans.

What Could the Bank of England Do on 5 November?

The Bank's September projections anticipated CPI inflation reaching around 3.75% in the fourth quarter of 2026 and slightly above 4% in the first quarter of 2027, based on the energy prices available at the time. The September inflation release adds to the uncertainty surrounding that outlook.

The Bank's next scheduled interest rate decision is on 5 November, following the Government's Budget on 28 October. Both events could influence market expectations and the wider borrowing environment. However, the inflation data alone is not enough to conclude that the Bank will raise rates. The Committee will assess the full range of evidence available before making its decision.

For borrowers, that leaves a short but potentially important period in which market pricing and lending conditions could change. The practical question is how many steps remain between agreeing mortgage terms and completing the transaction.

Why Mortgage Timing Matters Before Completion

Inflation was published on 21 October, the Budget is scheduled for 28 October and the Bank of England's next decision is due on 5 November. That places three significant economic or policy dates within a little over two weeks. A mortgage agreed in principle today may still need to pass through valuation, underwriting, legal work and other lender requirements before completion.

A formal mortgage offer can provide greater clarity on the proposed terms while it remains valid, but borrowers should check its expiry date and conditions. Offers are commonly valid for three to six months, according to Forbes Advisor's guide to mortgage offers, although the period varies by lender and circumstances. An offer is not an unconditional guarantee that a transaction will complete, and changes in the borrower's circumstances or failure to meet conditions can affect it.

Where an offer has not yet been issued, the rate and terms may remain subject to change before formal approval. Buyers should therefore establish what has been confirmed, what remains outstanding and whether the proposed timetable is realistic.

What Should Borrowers Do Now?

My preference is for clients to make decisions using the facts available to them, rather than relying on a prediction about the next Bank Rate decision. For a borrower buying a property, refinancing or arranging a substantial mortgage, that means reviewing the proposed loan, checking any offer expiry date and understanding the conditions that must be satisfied before completion.

It is also worth asking whether the financing structure remains suitable if rates move higher or the transaction takes longer than expected. A borrower should understand the effect of different borrowing costs on their wider finances and retain sufficient liquidity for the purchase and any associated expenses.

At Enness Global, we work with a network of more than 1,000 lenders, including private banks. The lenders most competitive on pricing are not necessarily those best suited to the largest or most complex borrowing requirements. Lender selection should reflect the client's circumstances, the property, the required loan size and the transaction timetable.

Inflation is above the Bank of England's 2% target and rose more than expected in September. With the Budget on 28 October and the next rate decision on 5 November, borrowers should focus on understanding their options and preparing for the next steps, rather than assuming either that rates will rise or that current pricing will remain available.

Important Information

Your home may be repossessed if you do not keep up repayments on your mortgage.

This article is for informational purposes only and does not constitute personal financial or mortgage advice. Mortgage rates and lending criteria may change, and availability depends on individual circumstances and lender requirements. Enness Global is a credit broker, not a lender. Speak to a qualified adviser before making a financial decision. Inflation and policy data are correct as at 21 October 2026.

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