Index of Production, UK: August 2025

• Production output was estimated to have decreased 0.3% during the three months to August 2025, compared with the three months to May 2025.

• The largest negative contributor to the three-monthly fall in August 2025 came from "electricity and gas" (down 2.6%); this was partially offset by increases in "water supply and sewerage" (up 1.0%) and "mining and quarrying" (up 0.2%), while "manufacturing" remained flat (0.0%).

• The decline in "electricity and gas" during the three months to August 2025 came from "manufacture of gas" (down 15.3%); this was partly because of strong growth in March 2025.

• Monthly production output was estimated to have increased 0.4% in August 2025; this follows a decline in July 2025 (down 0.4%) and a rise in June 2025 (up 0.9%).

• The rise in monthly production output in August 2025 resulted from increases in "manufacturing" (up 0.7%), "electricity and gas" (up 0.4%) and "water supply and sewerage" (up 0.3%); this was partially offset by a fall in "mining and quarrying" (down 2.3%).

• 8 of the 13 manufacturing subsectors saw a monthly increase in August 2025, with the largest positive contribution coming from "basic pharmaceutical products" (up 3.0%).

All data related to the Index of Production (IoP) are available on our Related data page.

The Index of Production (IoP) uses data from a variety of sources. It is calculated by taking turnover and removing the effect of price changes, or by using direct volume estimates. Most of these data are collected as "turnover values" through the Monthly Business Survey (MBS). Direct volume series are also collected by the Department for Energy Security and Net Zero (DESNZ), and the International Steel Statistics Bureau (ISSB) for steel industries. The MBS is fully online. Business owners can log on from any location and submit their data at an appropriate time.

From January 2018, Value Added Tax (VAT) data have also been included for 64 production industries for small-and medium-sized businesses. More information is available in our VAT turnover data in National Accounts: background and methodology. A comprehensive list of the IoP source data can be found in our Gross domestic product (GDP) data sources catalogue.

Response rates for August 2025

MBS response rates were 75.7% for August 2025, based on forms returned. This accounted for 85.7% of total turnover coverage of the sample population. For further information, see our current and historical MBS (production) response rates dataset.

Quality and methodology

The data reported in IoP bulletins and datasets are estimates that are subject to uncertainty, such as sampling variability and non-sampling error. More information is available in Section 2 of our Uncertainty and how we measure it for our surveys web page.

More quality and methodology information (QMI) on strengths, limitations, appropriate uses, and how the data were created is available in our Index of Production, UK QMI.

Accredited official statistics

These accredited official statistics were independently reviewed by the Office for Statistics Regulation in April 2014. They comply with the standards of trustworthiness, quality, and value in the Code of Practice for Statistics and should be labelled "accredited official statistics".

Revisions to Index of Production

This release includes revisions for July 2025 for the first time and also incorporates revisions from January 1997 to June 2025 in line with the quarterly national accounts published on 30 September 2025, consistent with Blue Book 2025, as per the National Accounts Revision Policy. 

Table 1 shows the revisions to Index of Production (IoP) and its main sectors from January 2025 to July 2025 since the last publication on 12 September 2025.

The large upward July 2025 revision in Section B is because of updated source data from the Department for Energy Security and Net Zero (DESNZ) for "Division 06 - Extraction of Crude Petroleum and Natural Gas".

Pausing of Producer Prices publications

Business prices data with corrected chain linking methods have been used in the IoP dataset for producer price indices (PPI), import prices indices (IPI) export price indices (EPI), and service producer price indices (SPPI) for all periods in this release. The quarterly SPPI estimates are splined to months for use in IoP calculations.

Any further updates to price data following the restart of the monthly business prices publication will be incorporated in IoP estimates in line with our national accounts revisions policy. 

Further information on the chain linking error in the producer prices dataset are detailed in our Methods update for Producer Price Indices (PPI) and Service Produce Prices Indices (SPPI) published on 10 July 2025. 

Seasonal adjustment

The monthly estimates of IoP are seasonally adjusted. Seasonal adjustment is the process of removing the variations associated with the time of year, or the arrangement of the calendar, from a data time series.

IoP estimates, as for many data time series, are difficult to analyse using raw data because seasonal effects dominate short-term movements. Identifying and removing the seasonal component leaves the trend and irregular components.

We use the X-13-ARIMA-SEATS approach to seasonal adjustment. Seasonal adjustment parameters are monitored closely and are regularly reviewed. For more information, please see our Seasonal adjustment methodology page.

In our IoP estimates, seasonal adjustment is applied at the industry level. The seasonally adjusted series are aggregated to create estimates by sector and total IoP output. As part of our quality assurance approach, residual seasonality checks are regularly completed by our time series analysis team on both the directly seasonally adjusted series and the indirectly derived aggregate time series.

This topic is explored further in our article updated on 30 September 2025.