The UK Office for National Statistics (ONS), in its consumer price bulletin published on 16 September, reported that the Consumer Prices Index (CPI) rose 3.1% in the year to August 2026. The annual rate had been 2.9% in July. CPI increased 0.5% month on month in August, compared with a 0.3% increase in August 2025. The CPIH measure, which also includes owner-occupiers’ housing costs, rose 3.3% over the year, up from 3.1% in July, and increased 0.5% during August. The measures have different coverage and should not be treated as interchangeable: CPIH includes additional housing costs that CPI excludes.

Transport prices rose 4.6% in the year to August, accelerating from 3.6% in July. The division rose 1.5% in the month, against a 0.4% increase in August a year earlier. Motor fuels contributed to the acceleration. In the ONS contribution analysis, transport made the largest contribution to annual CPI inflation, at 0.69 percentage points. Housing and household services made the largest contribution to CPIH, at 1.32 percentage points. The distinction illustrates how the same month’s price changes can be led by different spending groups depending on which costs an index includes.

Core CPIH, which excludes energy, food, alcohol and tobacco, remained at 2.9% annually, unchanged from July. CPIH goods inflation increased from 2.2% to 2.7%, while services inflation held at 3.6%. These components show that goods and services can move differently and contribute in different ways to the headline rate; the aggregate alone does not describe that mix. The ONS published the measures in monthly tables and time-series datasets. The figures refer to August and do not measure September prices. They are an observation of the reference month, not a forecast for later inflation or an announcement of a central-bank decision. A monthly change compares the price level with the preceding month, whereas an annual rate compares it with the same month a year earlier; the two rates therefore use different comparison periods. The index tracks a weighted basket of goods and services, so each division’s contribution reflects both its price movement and its weight in household spending. A change in one individual price is not equivalent to the overall inflation rate. ONS tables provide definitions and historical series to support comparisons.