UK inflation jumps to 3.5% as petrol hits its highest price since 2022

The numbers. The Consumer Prices Index (CPI) rose 3.5% in the year to September, after 3.1% in August. Prices rose 0.4% in the month alone, while a year earlier September was roughly flat. CPIH, which also counts owner occupiers' housing costs, rose 3.6% after 3.3%.

Where it comes from. Transport, and above all motor fuel, added the most. Petrol rose 8.2p a litre in the month to 169.5p. Diesel averaged 192.5p a litre, the highest since July 2022. Motor fuel overall was up 29.8% on the year. The BBC links this to disrupted oil supply from conflicts in the Middle East. Restaurants and hotels partly offset the rise.

Not just petrol. Core inflation, which leaves out energy, food, alcohol and tobacco, picked up to 2.8% from 2.6%. Services prices rose 3.7% after 3.4%. That matters: the rise is no longer only about oil.

Budget and debt. The same day the ONS said the government borrowed £25bn in September, £1.8bn more than a year earlier. The BBC says higher inflation pushed up interest costs on the debt. Healey presents his Budget on 28 October.

Confirmed facts

• UK consumer prices (CPI) rose 3.5% in the 12 months to September 2026, up from 3.1% in August.^[1][2]
• That is the highest rate since October 2025.^[1][2]
• CPI rose 0.4% on the month, compared with little change in September 2025.^[1]
• CPIH rose 3.6%, up from 3.3% in August.^[1]
• Petrol averaged 169.5p a litre, up 8.2p in the month and the highest since August 2022.^[1][2]
• Diesel averaged 192.5p a litre, the highest since July 2022; motor fuel overall rose 29.8% on the year.^[1][2]
• Core CPI rose to 2.8% from 2.6%, services to 3.7% from 3.4%.^[1]
• The government borrowed £25bn in September, £1.8bn more than a year earlier.^[2]
• The Budget is due on 28 October.^[2]
• The ONS publishes the next inflation figures on 18 November 2026.^[1]

Implications

• ConfirmedUK prices are rising faster than a month ago, with fuel as the main driver.
• Our readingThe Bank of England will find it harder to cut rates quickly while inflation speeds up.
• Our readingHealey has less room for generous measures in the Budget.

Still unknown

• Whether petrol and diesel keep rising in October.
• What exactly the 28 October Budget will contain.
• How the Bank of England reads these figures.

Who it affects

United Kingdom. Anyone holding pounds, UK stocks or bonds, or watching interest rates

Sources

1. Office for National Statistics: Consumer price inflation, UK: September 2026 October 21, 2026 · official
2. BBC News: Surging fuel prices push UK inflation rate to 3.5% ahead of Budget October 21, 2026 · media