Set ddata Consumer price inflation time series

16 September 2026

We have identified a minor error in the classification of several products in our scanner-based consumption segments from February 2026. This error has no impact on published headline growth rates in the Consumer Prices Index (CPI), the Consumer Prices Index including owner occupiers’ housing costs (CPIH) or the Retail Prices Index (RPI).

This error was caused by historical inconsistencies in the manual classification of a small number of products that were identified as part of wider system improvements.

This minor error has no impact on growth rates at divisional level. However, there are impacts at lower levels of aggregation of up to positive or negative 0.2 percentage points, for the periods February to July 2026 for some items within the food and non-alcoholic beverages, and alcohol and tobacco divisions. Full details of the impacts at these lower levels can be found via the Dataset accompanying the product classification error correction, February to July 2026.

In line with the Office for National Statistics (ONS) consumer prices revisions and correction of errors policy, we have not corrected the low-level indices for those months. However, we have corrected the error in this release. The ONS is reviewing its testing and quality assurance processes in response to this issue.