Estimates of quarterly greenhouse gas emissions (residence basis), UK: Quarter 1 (January to March) 2025

• We estimate that UK greenhouse gas (GHG) emissions on a residence basis were 145 million tonnes of carbon dioxide equivalent (MtCO2e) in Quarter 1 (Jan to Mar) 2025; this figure is similar to 144 MtCO2e in Quarter 1 2024.

• Residence-based GHG emissions were 1.77 tonnes of carbon dioxide equivalent (CO2e) per head in Quarter 1 2025; this is down 45.7%, or 1.49 tonnes of CO2e per head since Quarter 1 1999, when this series began.

• The UK emitted 155 tonnes of CO2e per million British pounds of economic activity (gross value added) in Quarter 1 2025; this is down 61.6% since Quarter 1 1999.

• These quarterly emissions estimates complement and draw on our annual residence-based emissions statistics.

• All estimates in this bulletin are produced using modelling techniques; those for all quarters of 2024 and Quarter 1 2025 are subject to greater uncertainty because final 2024 emission estimates are not yet available, so we have modelled data over five quarters.

Our estimates of total quarterly UK greenhouse gas (GHG) and carbon dioxide (CO2) emissions on a residence basis use modelling techniques. These are available up to Quarter 1 (Jan to Mar) 2025. All GHG and CO2 estimates in this bulletin are non-seasonally adjusted, unless otherwise specified.

We estimate that total Quarter 1 2025 emissions on a residence basis were 145 million tonnes of CO2 equivalent (MtCO2e). This is similar to the same quarter in 2024, when the estimate of emissions was 144 MtCO2e.

Table 1 shows the change in total quarterly emissions estimates, compared with the same quarter the previous year.

These estimates are subject to uncertainty, so should be interpreted with caution. The underlying input data, the estimates informing the model, and the modelling process itself, each introduce uncertainty that affects accuracy. The level of uncertainty is particularly high for all quarters of 2024 and for Quarter 1 2025. This is because we will not publish the final 2024 annual estimate of GHG emissions on a residence basis, to which we constrain these estimates, until June 2026.

Residence-based greenhouse gas (GHG) emissions were 1.77 tonnes of carbon dioxide equivalent (CO2e) per head in Quarter 1 (Jan to Mar) 2025. Emissions per head have decreased by 45.7%, or 1.49 tonnes of CO2e, since 1999, when this time series began.

More information can be found in Section 6: Methods used to produce the data in our Estimates of UK quarterly GHG emissions (residence basis) quality and methodology information (QMI).

Our residence-based emissions estimates are compiled in accordance with the United Nations System of Environmental Economic Accounting, which aligns with the UN System of National Accounts. This enables direct comparisons with important economic indicators, such as gross domestic product (GDP), as well as the calculation of greenhouse gas (GHG) emissions intensity and emissions per unit of economic output.

The UK emitted 155 tonnes of carbon dioxide equivalent (CO2e) per million British pounds of gross value added (GVA) in Quarter 1 (Jan to Mar) 2025. Emissions intensity has fallen by 61.6% from 404 tonnes of CO2e per million British pounds of GVA in Quarter 1 1999, when this series starts (see Figure 3).

Emissions intensity can be used to examine the relationship between economic growth and emissions. The general reduction in overall emissions intensity on this measure could be considered an indication that the UK is moving towards a lower carbon (emissions) economy.

This movement could be influenced by several factors, including changes in the structure of the economy and behavioural changes that may affect interaction between the economy and the environment. For example, it could be related to:

• some industries becoming more efficient in their production processes through the adoption of lower-emissions technologies

• changes in the composition of the economy, where there is a growing shift from higher- to lower-emitting economic activities, such as from manufacturing to services activities

• a combination of these factors

All estimates of GVA are subject to revisions. For more information, please see Section 8: Revisions to GDP in our GDP quarterly national accounts, UK: January to March 2025 bulletin.

Greenhouse gases

Greenhouse gases (GHGs) are those covered by the Paris Agreement, which has superseded the Kyoto Protocol. These include:

• Carbon dioxide (CO2)

• Methane (CH4)

• Nitrous oxide (N2O)

• Hydrofluorocarbons (HFCs)

• Perfluorocarbons (PFCs)

• Sulphur hexafluoride (SF6)

• Nitrogen trifluoride (NF3)

These gases contribute directly to global warming and climate change, because of their positive radiative forcing effect. The potential for each GHG to cause global warming is assessed in relation to a given weight of CO2, so all GHG emissions are measured as carbon dioxide equivalent (CO2e).

Residence basis

Estimates complied on a residence basis include data relating to UK resident and UK-registered businesses, regardless of whether they are in the UK or overseas. Emissions released in the UK by tourists and foreign transport operation are excluded. For more detailed comparisons of UK emissions measures, please see our Measuring UK greenhouse gas emissions article.

Temporal disaggregation

Temporal disaggregation is the process of deriving high-frequency data (for example, quarterly) from low-frequency data (for example, annual).

All greenhouse gas emission estimates presented in this bulletin and our accompanying dataset have been produced using temporal disaggregation and modelling techniques. They are therefore subject to uncertainty.

The main sources of information and predictor indicators for producing these estimates are:

• UK annual estimates of greenhouse gas (GHG) emissions on a residence basis from the Office for National Statistics (ONS)

• Energy Trends from the Department for Energy Security and Net Zero (DESNZ), which provides information on UK energy production, consumption, and trade, for energy overall and for specific fuels

We refer to residence-based (also known as production) emissions in this bulletin. Territorial emissions published by DESNZ is the measure generally used for GHG emissions targets, including net zero by 2050. Footprint (or consumption) emissions, published by the Department for Environment, Food and Rural Affairs, account for emissions from trade. More information on these three official measures of UK GHG emissions can be found in our Measuring UK greenhouse gas emissions article.

All estimates of the annual GHG series and the latest quarter of the energy trends are provisional and subject to revisions. A complete breakdown of emission data by more granular standard industrial classification (SIC) codes is required for our quarterly emissions model. We have published final estimates of emissions for 2023, with the final 2024 emissions due to be published in Summer 2026.

The whole time series is updated for each instance of this release, which means that the latest version supersedes all previous versions.

This bulletin presents non-seasonally adjusted estimates. Both non-seasonally adjusted and seasonally adjusted data are available in our accompanying dataset.

Official statistics status

As official statistics, these are produced in line with the Code of Practice for Statistics. We are committed to the continued innovation and improvement of these data. You can read more about the different types of official statistics on the UK Statistics Authority website.

We have published quarterly GHG emissions estimates regularly since July 2023. We have automated the production process using Reproducible Analytical Pipelines (RAPs), as described in GOV.UK's blog post.

For more information on the methods used, and the strengths and limitations of the data, see Section 6: Methods used to produce the data in our Estimates of UK quarterly GHG emissions (residence basis) quality and methodology information (QMI).

For further information, or if you have any views on these statistics or suggestions for improvement, you can contact us at environment.accounts@ons.gov.uk.

Strengths and limitations

The estimates used in the model and the modelling process are both subject to uncertainty. For instance, for periods where a base or reference year is unavailable (such as this quarter), we use "nowcasting" measures to extend the series for five quarters. This implies that the estimates for those periods are less accurate, compared with periods where a base or reference year is available.

More detailed information on the strengths and limitations of the estimates presented in this bulletin, is available in Section 6 of our QMI.

More quality and methodology information

More quality and methodology information on strengths, limitations, appropriate uses, and how the data were created is available in our Estimates of UK quarterly greenhouse gas emissions (residence basis) QMI.