CPI Y/Y
Actual: 3.1%
Previous: 2.9% (July)
Second consecutive month of increase
CPI M/M
Actual: 0.5%
Previous August 2025: 0.3%
CPIH Y/Y (most comprehensive measure)
Actual: 3.3%
Previous: 3.1%
Core CPI Y/Y (ex energy, food, alcohol, tobacco)
Actual: 2.6%
Previous: 2.6%, unchanged
The real driver, fuel explodes
Average petrol price: 161.3 pence/litre, highest since November 2022
Petrol up 9.1 pence/litre on the month (versus +0.3 pence a year earlier)
Diesel: 181.8 pence/litre, +14.2 pence on the month (versus +0.8 pence a year earlier)
Motor fuel Y/Y: +23.0% (versus +15.5% the prior month)
Transport Y/Y: 4.6% (versus 3.6% in July), the largest contributor to the CPI increase
Complete consistency with this series' narrative
Third consecutive CPI release in this series (eurozone, Canada, now UK) showing the same pattern, headline accelerating driven by energy/fuel, while core stays stable
Directly confirms the $100 oil threshold identified in the central bank repricing analysis as the dominant factor across every developed economy simultaneously
The real signal, core isn't moving
Core CPI and core CPIH both unchanged at 2.6% and 2.9%
Services stable at 3.4% (CPI) and 3.6% (CPIH), no acceleration in underlying inflation
Confirms the shock stays concentrated in energy rather than broad-based, consistent with the repeated read across this series
Housing, second contributor
Owner-occupied housing costs (OOH): 3.9% (versus 3.7%), third consecutive monthly rise
Electricity, gas and other fuels: 6.0% year-on-year, driven by heating oil
International comparison
UK at 3.1%, higher than France's (2.7%) and Germany's (2.9%) flash estimates
Consistent with the ECB's recent hike already documented in this series
Implications
GBP: this print complicates the BoE's read, consistent with the already-analyzed labor market that was softening (unemployment at 4.9%), creating a classic stagflationary tension, inflation accelerating while employment deteriorates
The rate pricing already documented in the prior analysis showed the BoE with 51bp of hikes expected by year-end and 57% odds of a hold at the next meeting, this print could reinforce the hawkish camp if the market reads the headline acceleration as the priority
But core stability should limit the reaction, the BoE having had pre-release access to labor market data before its September 14 meeting has likely already factored in both signals
GBP/USD: with US CPI having recently surprised to the upside, this UK print could narrow the dollar-versus-pound bias gap rather than widen it
Point of caution
ONS flags a minor classification error in scanner data from February to July 2026, no impact on headline rates but possible ±0.2pt impacts on certain sub-indices, worth keeping in mind for fine-grained reads of food/alcohol categories
The real test will be whether core stays stable in coming months or whether energy pressure starts to spread, exactly the "second-round effects" pattern the RBNZ and BoC explicitly monitor in their communications already analyzed in this series