Construction output in Great Britain: September 2025, new orders and Construction Output Price Indices, July to September 2025

• Total construction output is estimated to have grown by 0.1% in Quarter 3 (July to Sept) 2025 compared with Quarter 2 (Apr to June) 2025; new work decreased by 0.2%, while repair and maintenance grew by 0.6%.

• At the sector level, four out of the nine sectors grew in Quarter 3 2025; the main positive contributor to the increase was private housing repair and maintenance, which grew by 2.9%; the main negative contributor was private new housing, which fell by 1.9%.

• Monthly construction output is estimated to have grown by 0.2% in September 2025; this follows a downwardly revised decrease of 0.5% in August 2025 and an upwardly revised increase of 0.2% in July 2025.

• The increase in monthly output in September 2025 came solely from an increase in new work (0.7%), as repair and maintenance decreased by 0.5% on the month.

• Total construction new orders grew by 9.8% (£1,078 million) in Quarter 3 2025 compared with Quarter 2 2025; this quarterly increase came mainly from private commercial new work and private industrial new work.

• The annual rate of construction output price growth was 2.7% in the 12 months to September 2025.

Construction output estimates

Construction output estimates are monthly estimates of the amount of output chargeable to customers for building and civil engineering work done in the relevant period, excluding Value Added Tax (VAT) and payments to subcontractors.

Seasonally adjusted estimates

Seasonally adjusted estimates are derived by estimating and removing calendar effects (for example, leap years such as 2024) and seasonal effects (for example, decreased activity at Christmas because of site shutdowns) from the non-seasonally adjusted estimates.

Value estimates

The value estimates reflect the total value of work that businesses have completed over a reference month.

Volume estimates

The volume estimates are calculated by taking the value estimates and adjusting to remove the impact of price changes.

Quality and methodology

More quality and methodology information (QMI) is available in:

• our Construction output QMI

• our Construction output price indices (OPIs) QMI

• our New orders in construction QMI

Reasons for revisions to construction output in this release

This release contains revisions to construction output estimates from July 2025 onwards and is consistent with the National Accounts Revisions Policy. Revisions in this release are a result of:

• revisions in the nominal data; this includes revisions to the survey data

• revisions to seasonal adjustment factors, which are re-estimated every month and reviewed annually

• revisions to the input series for the Construction output prices indices (OPIs)

For further information on the revisions profile, see our Output in the construction industry revisions triangle (one-month growth) dataset and our Output in the construction industry revisions triangle (three-month growth) dataset.

Pausing of producer prices publications

Following the restart of monthly business prices publications on 22October 2025, business prices data with corrected chain-linking methods and updated historical weights have been used in the monthly gross domestic product (GDP) dataset for Producer Price Indices (PPI), Import Price Indices (IPI), Export Price Indices (EPI) and Service Producer Price Indices (SPPI) for July, August and September 2025 in this release. The quarterly SPPI estimates are splined to months for use in monthly GDP calculations.

These updates to business prices data will be incorporated in GDP estimates in line with our National Accounts Revisions Policy. 

Further information on the chain-linking error and the impact of methodological changes in the producer prices dataset are detailed in our Impact of correction to chain-linking methodology used in Producer Price Indices and Services Producer Price Indices: October 2025 article published on 22 October 2025. 

Seasonal adjustment

Our monthly construction estimates 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.

Construction 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.

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

In our monthly estimates, seasonal adjustment is applied at the sector level and the seasonally adjusted series are aggregated to create estimates by total 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.

Subnational and subsector construction output

Data on new orders supplied by Barbour ABI are used to model the breakdown of the overall output figures for Great Britain into the lower level and regional data. This is shown in Tables 1 and 2 of our Output in the construction industry: subnational and subsector dataset. More detail is available in our Quality assurance of administrative data used in construction statistics methodology.

Bias adjustment

Typically, since the move to monthly gross domestic product (GDP) estimates, an adjustment to address any bias in survey responses for construction output is applied to the early construction output monthly estimates. We show this in our Improvements to construction statistics: addressing the bias in early estimates of construction output, June 2018 article.

Response rates for September 2025 showed improvement compared with levels in recent years since the coronavirus (COVID-19) pandemic. The survey turnover response rate for September 2025 was 78.4%. This follows a response rate of 79.9% in August and 73.0% in July. We have continued not to apply a bias adjustment since May 2020 while we review this approach. More information on our response rates is available in our Output in the construction industry dataset.

Differences with monthly GDP construction estimates

In Blue Book 2021, we introduced a new framework to improve how we produce volume estimates of GDP for balanced years as part of the supply use process. This was explained in our Producing an alternative approach to GDP using experimental double deflation estimates article. This framework included the implementation of double-deflated industry-level gross value added (GVA) for the first time. This improvement was reflected in the GDP quarterly national accounts, UK: April to June 2021 bulletin and dataset and GDP monthly estimate, UK: August 2021 bulletin for the first time.

As a result, volume estimates in the monthly GDP and construction outputs releases will differ for the period 1997 to 2020. This is because the construction publication measures the volume of construction work (output), while the GDP series measures GVA (that is, output minus intermediate consumption). Construction estimates will align, but on a growth basis from January 2021 onwards.

Information and indicative effects of this change to industry-level GVA volume can be found in our Impact of double deflation on industry chain volume measure annual estimates article and our Impact of Blue Book 2021 changes on quarterly volume estimates of gross domestic product by industry article.

Accredited official statistics

These accredited official statistics were independently reviewed by the Office for Statistics Regulation in March 2019. They comply with the standards of trustworthiness, quality and value in the Code of Practice for Statistics and should be labelled "accredited official statistics".