UK public sector sustainability reporting 2026-27: what government bodies must disclose

His Majesty's Treasury sustainability reporting guidance for 2026-27 is mandatory for central government bodies that prepare annual reports under the Government Financial Reporting Manual. The first full year after transition relief brings no substantive change to the requirements, but it does make the reporting test harder to sidestep: environmental figures now need to sit within the same boundaries, controls and annual-report discipline as public spending.

The minimum return reaches beyond tonnes of greenhouse gases. In-scope bodies must connect domestic Scope 1 and Scope 2 emissions to energy use and gross expenditure, report waste and water alongside the related spend, and give a transaction-level account of any carbon credits they buy, hold or retire.

That combination changes the character of the disclosure. Once tonnes, kilowatt-hours, water and waste sit beside pounds spent, sustainability reporting stops being a separate environmental appendix and becomes part of public accounting.

The guidance also asks annual reports to connect those figures to governance, strategy, risk, performance and future plans. A department cannot meet that objective with a list of operational metrics if the reader still cannot tell which bodies are included, how estimates were made or whether the reported target belongs to the annual accounts at all.

Who must use the 2026-27 guidance

All ministerial and non-ministerial central government departments are in scope. Executive agencies and non-departmental public bodies must also apply the guidance when they have more than 500 employees, receive more than £500 million in operating income and funding, or have been instructed to do so by their sponsor department.

Schools and NHS bodies are excluded from this central government scope, while trading funds are included unless specifically exempt. Other public sector bodies may use the guidance voluntarily, but they remain responsible for any separate statutory or mandatory requirements that apply to them.

Treasury uses precise language. “Shall” marks a mandatory element; “should” marks a recommendation. In-scope bodies apply the guidance on a comply-or-explain basis, which means a gap needs a reason, planned action and timetable rather than a silent omission.

Smaller bodies are not automatically free of sustainability reporting. They still have to consider whether their environmental and social impacts produce information that would be material to users of the annual report, and consolidated departmental reports may need data from bodies that fall below the individual threshold.

The mandatory disclosures in one view

The 2026-27 minimum is concentrated in a relatively short group of operational measures. Material sustainability information beyond that minimum remains reportable, but it is selected through judgement rather than by adding every available metric.

The domestic minimum does not make overseas operations irrelevant. Material overseas Scope 1 and Scope 2 emissions are reported on a comply-or-explain basis, while material Scope 3 emissions can extend the account into procurement, business travel, leased assets, outsourced contracts and investments.

Waste and water follow the same physical-and-financial design as energy. A body should not report only that consumption fell or more material was recycled. The annual account should show the categories used, the relevant quantity and the gross cost, giving readers enough context to distinguish a genuine operational change from a cheaper contract, a boundary change or incomplete data.

For a fuller explanation of the three scopes, see our guide to Scope 1, Scope 2 and Scope 3 emissions. The underlying accounting methods are covered in the Greenhouse Gas Protocol guide.

The reporting boundary should follow the accounts

In most cases, a department's sustainability reporting boundary will match its financial reporting boundary. That lets users compare operational impacts with the organisation, assets and spending represented in the annual accounts.

Perfect alignment is not always possible. Joint ventures, associates, leases, shared buildings and outsourced services can sit across different forms of financial and operational control. Treasury allows judgement in those cases, but the selected method needs to be consistent across the departmental group and clear enough for a reader to understand what has been included.

The same principle applies to time. Metrics for a body's own operations should cover the financial year from 1 April to 31 March. Where supplier data or utility invoices arrive too late, the body may use reasonable estimates, provided the report explains the method and any plan to improve later data capture.

Changes to the boundary or baseline also need a visible bridge to prior figures. If an organisation rebaselines a target or a machinery-of-government change moves activity into a different group, the report should reconcile the old and new positions rather than presenting a broken trend as if it were continuous.

These are reporting-control questions as much as environmental ones. Our guide to sustainability reporting controls explains how ownership, source evidence, calculation methods, review and sign-off make a disclosed number traceable.

Greening Government Commitments are not the annual report

Central government bodies already collect environmental data for the Greening Government Commitments. That return can supply much of the operational information needed for an annual report, especially domestic Scope 1 and Scope 2 emissions, but the two frameworks are not interchangeable.

They use different scopes, boundaries and materiality tests. An exemption from the commitments does not automatically exempt a body from sustainability reporting in its annual accounts. Even where a target is removed, the underlying metric may still have to be disclosed.

The distinction is especially important in 2026-27 because the next central Greening Government Commitments for 2025 to 2030 had not been published when Treasury issued the guidance. Bodies should report relevant internal targets and baselines in the meantime, making clear that those figures are not unpublished government-wide targets.

The result should be an annual-report account designed for Parliament and other users, not a copied performance return. It needs to explain how environmental performance connects to the organisation's objectives, risks, spending and accountability.

Scope 3 and materiality decide what sits beyond the minimum

The guidance defines the 15 Scope 3 categories used by the Greenhouse Gas Protocol, but it does not ask every body to publish all 15 as if they were equally useful. The report should concentrate on value-chain emissions that are material to users and explain the boundary, method and limitations.

Treasury is unusually direct about the data problem. Scope 3 estimates can span several years, depend on proxies and lack the precision of annually measured operational emissions. That does not make them dispensable. It means they should not be presented with a confidence or comparability the underlying data cannot support.

Outsourcing also needs scrutiny. A contract or lease may move emissions outside the financial boundary without reducing them in the wider value chain. Where that shift is material, the annual report should explain the arrangement rather than allowing a smaller operational footprint to imply a reduction that has not occurred.

Materiality is therefore a filter, not an excuse. Treasury's principles warn against checklist reporting and excessive immaterial detail, but they also state that materiality cannot be used to omit a mandatory disclosure. A shorter report can be better if it makes the important boundaries and uncertainties easier to see.

Carbon credits need a transaction record

A public body that purchases, holds or retires carbon credits has to report the volumes and distinguish between reduction and removal credits. For removals, it should also separate nature-based approaches, such as woodland creation, from technology-based approaches such as direct air capture.

The report must describe the integrity of the credits and disclose expenditure on accredited purchases. Treasury says the minimum should not be read as encouragement to offset, and that public bodies should focus on reducing emissions as quickly as feasible. The guidance also restricts the use of credits in meeting Greening Government Commitment targets.

That is a stronger record than reporting a single net emissions figure. Purchased credits, credits still held and credits actually retired are different positions. Our guide to carbon credit retirement evidence explains the serial numbers, registry status and claim-use records needed to show what happened to a credit, while the carbon credit quality checklist covers the evidence behind the project itself.

What readers should be able to trace

A useful 2026-27 sustainability report will let a reader follow a figure from the annual account back to its reporting boundary, source data and method. Estimates should be identified, changes to baselines reconciled and gaps accompanied by a plan rather than buried in general language.

The operational figures should then connect to the rest of the annual report. Climate risks belong with governance and strategy, material emissions belong with performance, and environmental expenditure belongs with the account of how public money was used. The climate-related financial disclosure guide and our guide to climate scenario analysis explain the risk-reporting structure behind that connection.

For preparers, the immediate job is not to invent a larger sustainability section. It is to find the disclosures already produced across finance, estates, procurement and environmental teams, reconcile their boundaries and decide which additional information is material. For readers, the test is whether the final report makes performance and public spending easier to understand together.

Treasury's principles also favour proportion over volume. Parliament is identified as the primary user of central government accounts, and the report should contain enough detail to explain performance and accountability without obscuring them beneath immaterial material. The clearest report may therefore be shorter than an existing sustainability appendix while providing better reconciliations, clearer methods and more specific explanations.

Official sources

• Treasury: Sustainability Reporting Guidance 2026-27
• Treasury: Sustainability Reporting Guidance 2026-27 PDF
• Treasury: Appendix A, sustainability reporting concepts, principles and foundations
• Treasury: Government Financial Reporting Manual collection
• Treasury: climate-related disclosure application guidance
• Feature image: Treasury building by Tilman2007, Creative Commons Attribution-ShareAlike 4.0, via Wikimedia Commons