Table of contents
- Output information
- About this quality and methodology information report
- Important points
- Quality summary
- Quality characteristics of the environmental protection expenditure data
- Methods used to produce the EPE data
- Other information
- Annex 1: Types of expenditure captured by the Environmental Protection Expenditure Survey
- Cite this methodology
1. Output information
- National Statistic
- Frequency: Annual
- How compiled: Environmental Protection Expenditure Survey
- Geographic coverage: UK
- Last revised: 6 May 2026
2. About this quality and methodology information report
This quality and methodology report contains information on the quality characteristics of the data (including the European Statistical System five dimensions of quality (PDF, 3MB)), as well as the methods used to create it.
The information in this report will help you to:
understand the strengths and limitations of the data
learn about the existing uses and users of the data
understand the methods used to create the data
help you to decide suitable uses for the data
reduce the risk of misusing data
3. Important points
This report aims to provide users of the Environmental Protection Expenditure (EPE) Survey with information on the usability and fitness for purpose of these estimates.
The EPE Survey estimates form part of the Office for National Statistics (ONS) Environmental Accounts. This is part of a set of documents covering the UK Environmental Accounts estimates.
The EPE accounts, which capture estimates of expenditure, output, and use by government, businesses and households, are also produced by the ONS and have a separate Quality and Methodology Information report.
There is quality and methodology information available for other UK Environmental Accounts estimates, including:
4. Quality summary
Overview
Environmental protection expenditure (EPE) refers to the amount of economic resources devoted to all activities that have the prevention, reduction and elimination of pollution and of any other degradation of the environment as their main purpose. Measuring the financial commitment of an economy to environmental protection helps us to:
evaluate how environmental protection costs influence international competitiveness
assess the cost-effectiveness of environmental control mechanisms
The EPE accounts are also produced by the Office for National Statistics (ONS) and have a separate Quality and Methodology Information (QMI) report. Estimates from the EPE Survey are used in the EPE accounts. They form part of the environmental accounts, which are defined within the United Nations (UN) System of Environmental-Economic Accounting (SEEA) (PDF, 2.6MB). The SEEA is the internationally agreed standard for concepts, definitions, classifications, accounting rules and tables for producing accounts on the environment and its relationship with the economy. The SEEA uses concepts, definitions and classifications consistent with the UN System of National Accounts; this enables comparisons of the results of the environmental-economic accounts with the aggregates of the national accounts.
A range of EPE statistics is published and available to download from our UK Environmental Accounts releases, including:
Environmental Protection Expenditure Survey estimates: by industry and activity, which presents estimates from the EPE Survey
Environmental protection expenditure by general government (both central and local government)
Environmental protection expenditure accounts (including expenditure, output and use by general government, businesses and households)
The main data source for EPE by general government is estimates of the General government annual expenditure, which are available broken down by Classification of the functions of government (COFOG).
This QMI report will primarily focus on the EPE Survey. The EPE accounts have their own QMI report.
Users and uses
The potential uses for data come from a variety of international organisations, UK and other governments, and the research community.
Environmental protection expenditure data can be used by policymakers to assess the environmental impact of economic activities (resource consumption, air or water pollution and waste production) and to assess the actions (investments, technologies and expenditure) that are taken to limit the causes and risks of pollution.
Back to table of contents5. Quality characteristics of the environmental protection expenditure data
Geography
Estimates of environmental protection expenditure (EPE) by general government and industry are available at a UK level and not further disaggregated by geography.
Coherence and comparability
Estimates of EPE by industry and general government are comparable over time. However, the time series is subject to revision if there are methodological improvements, changes to reporting requirements or data revisions from suppliers.
It should be noted that the EPE Survey, used to provide EPE by industry and activity estimates, migrated from the Department for Environment, Food and Rural Affairs (Defra) to the Office for National Statistics (ONS) in 2016.
Prior to 2015, data were collected by a Defra survey in 1994 (pilot), 1997, and then annually between 1999 and 2013. In 2016, the survey migrated to the ONS and was despatched in September 2016 to collect data for 2015. As a result of the migration, no data were collected for 2014. Results from the EPE Survey from 2015 onwards are not comparable with previous data because of differences in the methodology between Defra and the ONS.
Specific differences include:
the 2013 EPE commissioned by Defra sampled 1,166 companies and had a response rate of 21%; in contrast, the 2017 EPE Survey despatched by the ONS sampled around 3,000 businesses and achieved a response rate of 74%
a number of questions were removed when the EPE Survey migrated to the ONS
the layout and wording of the form was changed
In 2017, for the 2016 reporting period, a question was added to the ONS EPE Survey to obtain estimates of external operational expenditure. Before this, information was collected only on in-house operational expenditure (please see Annex 1 for definitions). From the same reporting period onwards, the survey collected information on the profits from the disposals of any capital assets that had been used for environmental protection purposes.
Our EPE Survey was paused in 2024, so no data were collected for the 2023 reporting period. Figures for 2023 are not available and are therefore not included in any published tables. Any analysis, comparisons, or interpretations must consider the absence of 2023 data to avoid inaccurate conclusions. This pause affects data availability only and does not affect the survey's methodology or the data presented for adjacent years.
Time series of data are available in our EPE by general government dataset and our EPE by industry and activity dataset.
Timeliness and punctuality
The ONS aims to publish EPE by general government and industry two years after the reference period. For example, 2017 data are published in 2019. The ONS aims to publish the data in the most timely manner available.
For more details on related releases, the ONS release calendar is available online and provides 12 months' advance notice of release dates. If there are any changes to the pre-announced release schedule, we will draw public attention to the change, and the reasons for the change will be explained fully at the same time, as set out in the Code of Practice for Statistics.
Concepts and definitions
The United Nations (UN) System of Environmental-Economic Accounting, the UN System of National Accounts, and the European System of Accounts (ESA) provide a framework for producing internationally comparable statistics on the environment and its relationship with the economy. EPE information is reported broken down by Classification of Environmental Protection Expenditure (CEPA) classification.
EPE supports understanding of society's response to the challenge of environmental degradation and depletion of natural resources, and the potential for economic activity to be based on environmentally friendly activities.
It is important to note that a low level of EPE does not necessarily mean that a country's government or industries are not effectively protecting the environment. If investment has been previously made in equipment that reduces or cleans waste products, then the cost of maintenance of these will be small compared with the cost of introducing new equipment.
Where investment has been made in equipment that is integrated within a production process, only the additional cost over and above equivalent but less environmentally friendly equipment is included in the estimates provided. By contrast, the total cost of any equipment that is not integrated into a production process is included in the estimates. This means that if governments or industries have more focus on reducing and cleaning pollution as part of their production process, their expenditure is likely to be less than for those that do not change their production processes and instead focus on cleaning the pollution produced by them.
Back to table of contents6. Methods used to produce the EPE data
We use the Environmental Protection Expenditure (EPE) Survey to provide estimates of EPE by industry and activity.
The main data source for EPE by general government is estimates of the General government annual expenditure, which are available broken down by Classification of the functions of government (COFOG). Data on current expenditure, subsidies and capital investment are used. Our Environmental protection expenditure: general government dataset is different from the estimates of general government in the EPE accounts. The calculations used in the accounts are given in the EPE accounts Quality and Methodology Information report.
The EPE Survey was designed to collect information on how much industries spend on protecting the environment. The EPE Survey focuses on four types of expenditure (please see Annex 1 for detailed definitions), which are:
external operating expenditure
in-house operating expenditure
end of pipe capital expenditure
integrated capital expenditure
The EPE Survey also collects profits made from disposal of capital assets that have been used for environmental protection purposes.
The target population for the survey is specified by Eurostat as including the following industries:
mining and quarrying (B)
manufacturing (C)
electricity, gas, steam and air conditioning supply (D)
water collection (E36)
For more information on industry classification, please see the current Standard Industrial Classification (SIC) used in classifying businesses and other statistical units.
Questionnaires are sent to the approximately 3,000 UK businesses that are selected using the Inter-Departmental Business Register (IDBR) as the sample frame. The design is a stratified single-stage random sample, with the target population being stratified by industry and employment size. Sample selection occurs independently within each stratum.
All businesses with 250 employees or above are selected, together with a random sample of businesses from each of the other strata, defined by two-digit SIC 2007 industry and employment size band.
All responses that fail edit rules are investigated and queried with the respondent to validate the responses and obtain explanations for data anomalies. Sources such as IDBR and business websites are also used to investigate data. Various quality assurance exercises, such as validating nil returns via telephone calls directly with the businesses, are also carried out.
Non-response can reduce the precision of estimates and affect the overall quality of the statistics. For the EPE survey, where businesses have item (partial) non-response and the sum of components (subtotals) are not equal to totals, this is addressed through imputation. Imputation uses other survey variables to predict plausible values for missing data. These variables form the imputation classifications. Effective imputation classifications should:
- address any non-response bias that has been identified
- act as strong predictors of the missing variable
Poorly specified classifications may introduce error or bias into the final estimates.
If one component (subtotal) is missing and there is a difference between the components and total, then the missing component is assigned the difference. Where more than one component (subtotal) is missing, data are imputed using imputation classes.
Businesses that provide valid data are grouped into the relevant imputation classes, which group together similar industries.
For each complete respondent, proportions for each component (subtotal) contributing to the total are calculated and the median proportion is determined for each component within each imputation class. These median proportions are then rescaled to sum to 1 and applied to the total to determine imputed values for the missing components (subtotals) to ensure additivity.
Each imputation class must contain a minimum of 10 complete responses to ensure reliable estimation. This reduces the risk of imputed values being overly influenced by extreme observations. Where this threshold is not met, the next classification level in the hierarchy is used.
After imputation, responses are weighted to represent non-sampled businesses within the same stratum. The expansion estimator (Horvitz--Thompson estimator) is used to produce population‑level estimates of environmental protection expenditure. This approach accounts for the survey design through the probabilities of selection. Sample totals in a stratum are scaled to the population by multiplying them by the ratio of the number of businesses in the population to the number of responses in that stratum; unit-level non-response is therefore dealt with via reweighting. The weighted responses are then aggregated to produce the final estimates.
Disclosure control
Our Statistical Disclosure Control Policy sets out the standards for safeguarding the information provided in confidence to us. "Disclosure control" refers to the methods that reduce the risk of confidential information being published in any official statistics. These methods are applied if ethical, practical or legal considerations require the data to be protected. Disclosure control involves modifying data so that the risk of identifying individuals is reduced; at the same time, it attempts to find a balance between improving confidentiality protection and maintaining an acceptable level of quality in the published data.
Accuracy
As in all surveys, the estimates in the EPE Survey are subject to various sources of error. The total error in a survey estimate is the difference between the estimate derived from the data collected and the true (unknown) value for the population. The total error consists of two main elements; these are the sampling error and the non-sampling error. The EPE Survey was designed to minimise these errors.
Sampling error
This occurs because estimates are based on a sample rather than a census of the population. The results obtained for any single sample may, by chance, vary from the true values of the population, but we would expect the variation to be zero on average over a number of repeats of the survey. Sampling error is minimised through the use of a stratified random sample.
Non-sampling error
There is potential for non-sampling errors that cannot be easily quantified. These can be caused by coverage issues, measurement and non-response. Steps are taken to minimise non-sampling error. For example, returned information is run through a series of validation checks to identify any errors. Data that fail the validation checks are queried with respondents to confirm or correct the original data. Following dispatch of the questionnaire, up to two reminders are sent to businesses that have not responded. Response-chasing exercises are also carried out to increase the response rate.
Revisions to previous data may occur. Revisions are not uncommon during the first few years of a survey being conducted. Reasons for revisions include:
the incorporation of additional data received from businesses who have been sampled in multiple years of the survey
changes to data as a result of businesses revising their previous submissions
developments in methodology and changes to the questionnaire
7. Other information
More information on environmental protection expenditure (EPE) and topics related to UK Environmental Accounts is available, including:
EPE accounts quality and methodology information (QMI) report
UN System of Environmental-Economic Accounting
Classification of Environmental Protection Activities information
Back to table of contents8. Annex 1: Types of expenditure captured by the Environmental Protection Expenditure Survey
The Environmental Protection Expenditure (EPE) Survey focuses on four types of expenditure as well as profits made from disposals.
External operating expenditure
This refers to operating costs paid to external organisations for treatment, disposal or investigation relating to waste water management, protection of ambient air and climate, and solid waste management. All other potential types of environmental protection expenditure are captured within the "other" category and may include expenditure aimed at the protection of soil or groundwater, noise abatement, protection of biodiversity or protection against radiation.
In-house operating expenditure
This refers to on-site management costs for the treatment, disposal or investigation relating to waste water management, protection of ambient air and climate, and solid waste management. All other potential types of environmental protection expenditure are captured within the "other" category and may include expenditure aimed at the protection of soil or groundwater, noise abatement, protection of biodiversity or protection against radiation.
End of pipe capital expenditure
This refers to capital expenditure for methods, technologies, processes or equipment designed to collect and remove pollution and pollutants after their creation. This might include investment in plants or equipment that treat generated pollutants, such as an effluent treatment plant or exhaust air scrubbing system, or investment in ensuring their safe disposal, such as a solid waste compactor.
Integrated capital expenditure
This refers to investment in methods, technologies and equipment that are integrated within the businesses' overall activity, where the primary aim of the expenditure is to reduce any pollutants generated. The expenditure captured here includes only the element that specifically relates to the additional cost of the environmentally friendly process compared with a cheaper and less environmentally friendly alternative. An example here would be the difference in the cost to a business of purchasing more precise cutting machinery, that led to the production of smaller amounts of waste, compared with the business purchasing cheaper but less precise cutting machinery that might lead to the production of larger amounts of waste.
Disposals
This refers to profits from the disposal of any capital assets that have been used for environmental protection purposes.
Back to table of contents9. Cite this methodology
Office for National Statistics (ONS), released 6 May 2026, ONS website, methodology, Environmental Protection Expenditure (EPE) Survey QMI