Why has UK inflation jumped to 3.5% & what does it mean for the pound?

By David Stritch, Senior Multicurrency Analyst, Caxton | 21 October 2026

Why has UK inflation jumped to 3.5%, and what does it mean for the pound?

UK inflation rose to 3.5% in September, above forecasts and the highest reading in 11 months. Fuel prices were the main driver, but rising costs in recreation, culture and household services suggest price pressures are spreading. That makes a Bank of England rate hike on 5 November look very likely, which is broadly supportive for sterling.

1 Minute Market Rundown

• UK headline inflation printed at a punchy 3.5%, above estimates and up from 3.1% in August.
• Core inflation, which strips out food and energy, rose to 2.8%, showing service costs are rising too.
• Transport remains the main culprit, moving in tandem with oil prices above $100 a barrel.
• A 25 basis point Bank of England hike on 5 November now looks close to a done deal.

What happened to UK inflation in September?

Prices rose faster than expected. British consumer prices rose 0.4% in September from August, above the 0.3% forecast, taking annual inflation to 3.5% from 3.1% and its highest since October 2025. The headline figure also exceeded the 3.4% median forecast in a Reuters poll. investingrallies

Beneath the headline, the picture was firmer still. Core CPI, which excludes energy, food, alcohol and tobacco, rose 2.8% in the 12 months to September, up from 2.6% in August, while services inflation, which the Bank of England views as a guide to underlying price pressures, rose to 3.7% from 3.4%, above economists’ 3.6% forecast. investingrallies

In truth, the figures went the only way they really could: up. Oil has been above $100 a barrel since early September and was already elevated before that, so a fuel-led jump in headline inflation was always on the cards.

Why is this inflation reading more worrying than it looks?

Because the rise isn’t just about fuel. Transport added 0.25 percentage points to the change in the annual rate, which is the expected part of the story. The more concerning detail is that recreation and culture contributed 0.10 percentage points, and housing and household services a further 0.06.

This is starting to look like the “second-round effects” Bank of England policymakers have repeatedly warned about. A second-round effect is when an initial price shock, such as energy, feeds into wages and the prices of other goods and services, making inflation stickier. The 12-month rate for housing and household services was 4.5% in September 2026, up from 4.3% in August. ons

When aggressive price rises appear in more labour-intensive areas of the economy, inflation stops being a single-sector problem and starts to behave like a general pathogen. That is exactly what central banks fear most.

How did the pound react?

Sterling’s reaction was measured. At 7:30am this morning, GBP/USD was trading at around 1.3305, up 0.33% on the day, while GBP/EUR stood at 1.1866, down 0.20%. Against the Australian dollar, the pound was at 1.9062, and against the Canadian dollar 1.8770.

The weakness against the euro is worth noting. GBP/EUR is down almost 2% over the past month and more than 3.5% year to date, partly because the European Central Bank has already acted: the ECB hiked rates for the second time this year in September. The Bank of England, in other words, is playing catch-up. thestandard

What is the market watching next?

The next big date is the Bank of England’s decision on 5 November. The current Bank Rate of 3.75% may no longer be sufficiently restrictive, according to analysts at Pantheon Macroeconomics, who now expect two further interest rate rises, in November 2026 and February 2027. Goldman Sachs and Citigroup moved to forecasting a November hike back in September. share-talkshare-talk

Before that comes the UK Budget, where today’s figures may intensify calls for household support. Then, on 18 November, the October inflation data will capture the 1 October Ofgem price cap rise, partly offset by a cut in VAT on utility prices, expected to reduce CPI inflation by 0.2 percentage points for 12 months starting in October. UK inflation jumps to highest in nearly a year at 3.5% - TLT News +2

What does this mean for businesses and individuals with currency exposure?

Higher UK interest rates tend to support the pound, but a supportive backdrop does not remove volatility, especially with a Budget and a central bank decision landing within days of each other.

• Paying overseas suppliers: if you have euro or dollar invoices due in the coming months, this is a period where rates could swing sharply around 5 November.
• Receiving foreign revenue: a stronger pound reduces the sterling value of overseas income, so exporters should know their break-even rate.
• Making large personal transfers: property purchases or wealth moves abroad are particularly exposed to sudden moves around major announcements.

A forward contract, which fixes an exchange rate today for a payment later, is one way businesses remove that uncertainty from their planning.

David’s view

My read is that a 25 basis point hike on 5 November is now as close to certain as these things get. What’s interesting is that the long end of the expectations curve hasn’t moved. Markets believe the Bank will act now, but they aren’t yet pricing a prolonged tightening cycle. If the October data confirms that price rises are spreading into services, that assumption could be tested, and sterling would be the first place you’d see it.

FAQ

What is the UK inflation rate in September 2026?
UK CPI inflation was 3.5% in the 12 months to September 2026, up from 3.1% in August. It is the highest rate since October 2025.

Why is UK inflation rising?
The main driver is transport, particularly motor fuels, with oil above $100 a barrel since early September. Rising prices in recreation, culture and household services suggest pressures are broadening.

Will the Bank of England raise interest rates in November 2026?
Markets and many major banks expect a 25 basis point increase on 5 November, which would take Bank Rate from 3.75% to 4%. The decision is data-dependent and not confirmed until announced.

Does higher inflation make the pound stronger or weaker?
It depends on the response. If higher inflation leads the Bank of England to raise rates, that can support sterling. If inflation hurts growth without a policy response, it can weigh on the pound.

What are second-round effects?
They occur when an initial price shock, such as energy, feeds through into wages and the wider prices of goods and services, making inflation harder to bring down.

Plan ahead of the Budget and the Bank of England

With a Budget and an interest rate decision landing within a fortnight, now is a sensible time to review your currency exposure. Join our pre-Budget briefing, [2026 UK Budget Insights], or speak to one of Caxton’s multicurrency dealers about tools such as forward contracts and rate alerts that can help you plan with more certainty.

Please be aware the rates above represent the market rate at 7:30am. Contact your Caxton dealer or check online for a live quote.

This article is for information only and does not constitute financial advice. Exchange rates can move quickly and past performance is not a guide to future performance.