Public Sector Supplier Carbon Requirements

If you bid for public sector work in the UK, carbon is now part of the tender. Suppliers we speak to say Scope 3 emissions have become a pass/fail question on new tenders over the last 12 to 18 months. One supplier that delivers services for councils told us buyers now expect a credible Scope 3 figure, not just Scope 1 and 2.

The rules differ depending on who is buying. Central government, councils, the NHS and the devolved governments each set their own expectations, and some are changing in 2027. This guide sets out what each buyer asks for, what we are hearing from suppliers, and how to get ready before your next tender is published.

What do UK public sector buyers ask suppliers for on carbon? Most ask for a Carbon Reduction Plan: a published, board-approved document that commits to net zero by 2050 and reports Scope 1, Scope 2 and at least five Scope 3 categories. Central government requires one for contracts above £5 million a year. The NHS asks for one, or a lighter Net Zero Commitment, on all new procurements. Many councils set their own carbon questions and evaluation weightings.

UK public sector carbon requirements compared

Central government: PPN 006 and Carbon Reduction Plans

The Procurement Act 2023 took effect for new procurements on 24 February 2025. Alongside it, the Cabinet Office published PPN 006, which replaced PPN 06/21 for procurements advertised from that date. The government says the update reflects new terminology and is not a change in policy.

PPN 006 applies to central government departments, their executive agencies and non-departmental public bodies. It covers contracts with an estimated value above £5 million a year, including VAT, where a Carbon Reduction Plan is relevant and proportionate to the contract. Buyers use the plan as a condition of participation, so a missing or non-compliant plan can stop your bid.

According to the technical standard, a Carbon Reduction Plan must:

• Commit to net zero by 2050 for your UK operations
• Report Scope 1 and Scope 2 emissions in tonnes of CO2e, using UK Government conversion factors
• Report five Scope 3 categories: upstream transportation and distribution, waste generated in operations, business travel, employee commuting, and downstream transportation and distribution
• Set out the carbon reduction measures you have in place
• Be signed off by a director and approved by the board or equivalent
• Be published on your UK website, with a prominent link from the homepage
• Be updated every year, within six months of your financial year end

Our guide to PPN 006 and PPN 06/21 covers the plan itself in more detail.

Social value

Central government also scores social value. Under PPN 002, mandatory for procurements started on or after 1 October 2025, buyers must give social value a minimum 10% weighting. One of its outcomes, sustainable procurement practices, sits under the mission to make Britain a clean energy superpower, so buyers can choose to score environmental commitments.

From 2027, social value scoring no longer covers the environment. PPN 026, published in August 2026, applies to central government procurements worth £1 million or more that start on or after 1 January 2027. It raises the minimum weighting to 20% for contracts of £5 million or more, but focuses on two outcomes: good jobs and skills. It has no environmental outcome. From 2027, expect central government carbon requirements to come mainly through the Carbon Reduction Plan and the contract specification.

Do councils require a Carbon Reduction Plan?

Not under PPN 006, which is written for central government and does not cover councils, so local authorities set their own rules. In practice, many ask for something similar, and some go further on scoring. Three examples:

• Greater London Authority Group. The GLA Group's Responsible Procurement Supplier Charter (June 2026) asks suppliers to produce an organisational Carbon Reduction Plan for contracts of £5 million and over, and to measure, reduce and report emissions linked to delivering its contracts where possible.
• Manchester City Council. Manchester applies a 30% weighting to tenders: 20% for social value and 10% for environmental impact and zero carbon, according to its social value and zero carbon guidance.
• Cardiff Capital Region councils. Council papers from Monmouthshire say that since March 2024, all tenders over £5 million include a Carbon Reduction Plan requirement, using guidance adopted by all ten councils in the region.

Thresholds, templates and weightings vary from one council to the next, so read each tender pack closely. Councils also face their own net zero targets, and the goods and services they buy are a large part of their footprint, so they look closely at their suppliers' emissions.

What does the NHS require from suppliers?

The NHS has the clearest published timeline. Its Net Zero Supplier Roadmap sets these milestones:

• April 2022: all NHS procurements include a minimum 10% net zero and social value weighting.
• April 2023: suppliers on new contracts above £5 million a year publish a Carbon Reduction Plan covering UK Scope 1, 2 and a subset of Scope 3.
• April 2024: the requirement extends, proportionately, to all new procurements.
• April 2027: suppliers publicly report targets and emissions, and publish a Carbon Reduction Plan covering all relevant global Scope 1, 2 and 3 emissions.
• April 2028: new requirements for carbon footprints of individual products supplied to the NHS.
• 2030: suppliers can only qualify for NHS contracts if they show progress through published progress reports and continued emissions reporting.

NHS England's Carbon Reduction Plan guidance explains how this works now. Procurements of £5 million a year or more need a full plan. Smaller procurements above the relevant threshold usually need a Net Zero Commitment, a published commitment to net zero by 2050 or earlier. The NHS encourages a 2045 target. The April 2027 milestone is the largest change: it moves from five Scope 3 categories to all relevant Scope 3 emissions.

The Evergreen Sustainable Supplier Assessment

NHS England also runs the Evergreen Sustainable Supplier Assessment, a self-assessment that any supplier to NHS England, integrated care boards or NHS trusts can complete on Atamis, the NHS e-procurement system. You get a sustainability maturity score, valid for 12 months. It is not usually scored in tenders, with two exceptions: suppliers bidding for new NHS Supply Chain frameworks must submit it and reach Level 1, and NHS England medicines tenders have required a submission since January 2024.

Wales and Scotland

In Wales, WPPN 006 asks Welsh Government, NHS Wales and Welsh Government sponsored bodies to require a Carbon Reduction Plan, or equivalent, for contracts of £6 million or more including VAT. It is recommended as best practice to other devolved Welsh authorities. Below the threshold, buyers are urged to consider asking for plans in high-emission categories such as manufacturing, construction, transport, and health and social care.

Scotland has its own procurement law. The Procurement Reform (Scotland) Act 2014 requires contracting authorities to consider how a procurement can improve environmental wellbeing. Scottish Government guidance (SPPN 3/2022) asks buyers to seek a climate change plan from bidders on high-value, high-impact contracts, and expects bidders to show net zero commitments by 2045.

What we're hearing from suppliers

The published rules set a minimum. Conversations with suppliers bidding for public contracts show how tenders are being run in practice.

• Scope 3 is pass/fail. Several suppliers told us Scope 3 has become a pass/fail criterion on new tenders in the last 12 to 18 months.
• Some buyers want Scope 3 in year one. Some public sector clients require Scope 3 reporting within the first year of a contract. The worry for bidders is winning the work and then being unable to deliver the number.
• A partial set looks incomplete. Suppliers prefer to report all relevant Scope 3 categories rather than a handful, because a partial inventory raises questions about what has been left out.
• Methodology gets checked. Boards and finance teams scrutinise the methods and assumptions. A defensible, explained number matters more than the figure on its own.
• Spend data is the usual starting point. Many suppliers' own suppliers will not share primary data, so a spend-based calculation for purchased goods and services is a common first step.
• Group structures add work. Organisations with several companies or charities in one group find it easier to measure at group level first, then split the footprint by entity for each contract.
• Budget cycles set the timing. Many prefer a consultancy-led first footprint before committing to software, and plan the work around budgeting season.

How to get tender-ready

1. Measure Scope 1 and 2 now. Fuel, gas and electricity data is usually easy to collect, and it is the minimum every buyer asks for.
2. Measure all relevant Scope 3 categories. Cover at least the five PPN 006 categories, then add purchased goods and services and any other material categories. The NHS will expect all relevant Scope 3 from April 2027.
3. Write a methodology note. Record your boundary, data sources, emission factors and assumptions, including where you used spend-based estimates and how you plan to replace them with supplier data.
4. Decide group or entity. If you bid through more than one legal entity, measure the group first and allocate emissions to each entity so you can answer each tender.
5. Get board sign-off. PPN 006 requires sign-off by a director and board approval. Brief them on the method before they sign.
6. Publish your Carbon Reduction Plan. Put it on your UK website with a clear link from the homepage, and keep previous versions online.
7. Update it every year. Refresh the footprint and the plan within six months of your financial year end, and show progress against your target.
8. Plan your timeline. A first full footprint usually takes 8 to 12 weeks, so start well before the tender is published.

How Zevero helps

Zevero combines carbon accounting software with in-house carbon experts. For suppliers bidding for public sector work, we help you:

• Measure a corporate carbon footprint across Scope 1, 2 and all relevant Scope 3 categories, aligned with the GHG Protocol
• Write a Carbon Reduction Plan that meets PPN 006 and NHS requirements
• Start with a consultancy-led first footprint, then move onto the platform when you are ready
• Document a defensible methodology that your board and finance team can stand behind
• Report at group level and split by entity for each contract
• Set reduction targets, including science-based targets, and track progress each year

Most clients have a full footprint in 8 to 12 weeks. If you also expect wider reporting duties, read our guide to the UK Sustainability Reporting Standards. To get ready for your next tender, book a demo.