Carbon Reduction Plan: A PPN 06/21 Guide for UK SMEs

If you bid for UK government contracts, Procurement Policy Note 06/21 has probably already changed your procurement life. Introduced in 2021 and in continuous force since, PPN 06/21 requires suppliers on any central government contract valued over £5 million (including VAT) to publish a Carbon Reduction Plan (CRP) — before they can be awarded the contract.

For a UK SME supplier, "our current emissions are X, our target is Y, our commitments are Z, signed by the MD" is not optional content marketing. It is a gateway requirement for winning the tender.

This guide explains what a Carbon Reduction Plan actually contains, which contracts trigger the requirement, how to build one as an SME, and how to avoid the usual traps that cause suppliers to fail a procurement check on the CRP alone.

What is PPN 06/21?

Procurement Policy Note 06/21 is the UK government's procurement policy on taking account of Carbon Reduction Plans in the procurement of major government contracts. It applies to all central government departments, their executive agencies, and non-departmental public bodies (NDPBs).

When a department runs a procurement above the threshold, it must require all bidders to submit a qualifying Carbon Reduction Plan as part of their selection stage response. A missing or non-compliant CRP means the bid is non-compliant, regardless of the commercial merits.

The policy sits inside the broader Cabinet Office procurement policy notes collection and has been aligned with Procurement Act 2023 implementation without being materially rewritten.

Does PPN 06/21 apply to your contract?

The test is a three-part filter. All three must be true.

Test	Question	In scope?
Buyer	Is the contracting authority a central government department, executive agency, or NDPB?	In-scope buyers are listed in Appendix A of PPN 06/21
Value	Is the anticipated contract value £5M or more (including VAT) per annum?	Yes → CRP required
Timing	Is the tender being run now (post-policy effective date)?	PPN 06/21 has been in force continuously since 2021

Contracts with local authorities, the NHS, or devolved administrations (Scotland, Wales, Northern Ireland) are not automatically in scope of PPN 06/21, though several of those bodies have adopted similar CRP requirements in their own procurement. Check the individual contract notice.

Framework agreements above the threshold are in scope. Call-offs from frameworks are usually not, unless the framework terms require it.

What goes in a qualifying Carbon Reduction Plan

PPN 06/21 sets out five mandatory areas. A CRP that is missing any of these will be rejected.

1. Baseline emissions footprint

Your starting point in tonnes of CO₂ equivalent (tCO₂e), covering a defined 12-month reporting period. The baseline must include:

Scope 1 — direct emissions from fuel combustion you control (gas boilers, company vehicles, refrigerant leaks). See our guide on Scope 1 and 2 emissions for how to calculate each.
Scope 2 — indirect emissions from purchased electricity, heat, or steam (location-based method)
Scope 3 — a defined subset of value-chain emissions, at minimum: business travel, employee commuting, upstream transportation and distribution, downstream transportation and distribution, and waste generated in operations

PPN 06/21 explicitly does not require full Scope 3 — the subset above is the minimum. You can voluntarily include more Scope 3 categories if you calculate them (purchased goods, capital goods, use of sold products, etc.) but your baseline must at minimum cover the PPN-mandated subset.

Use the UK government conversion factors (2025 edition is current) to convert activity data (kWh, litres, miles) to emissions.

2. Current year emissions

The same calculation for the most recent year. This is what gets updated annually. The gap between baseline and current year shows progress.

3. Emissions reduction targets

A clear target with:

Scope covered (Scope 1, 2, and which Scope 3 categories)
Base year (the year your baseline covers)
Target year (when the reduction will be achieved)
Percentage reduction from base year to target year

A qualifying target must also include a Net Zero by 2050 commitment (or earlier) — this is explicit in PPN 06/21.

The target does not have to be Science Based Targets initiative (SBTi)-validated, but alignment with SBTi methodology strengthens the plan. For SMEs, a self-defined target with a clear reduction trajectory is acceptable.

4. Carbon reduction projects

Specific, actionable projects you are undertaking. This is the section where suppliers most often trip up — generic statements like "we will reduce our emissions" do not satisfy the requirement. Examples of what does qualify:

"Switched to a 100% REGO-backed renewable electricity tariff across all three UK sites in April 2025 (eliminating ~120 tCO₂e/yr from Scope 2)"
"Replacing our 6-vehicle diesel van fleet with electric vehicles on a 24-month rolling schedule starting October 2025"
"Completed a building-fabric upgrade at our Leeds warehouse in 2024, reducing natural gas consumption by 31% (measured in subsequent 12 months)"

The test is: could a procurement officer verify this project happened? If yes, it counts. If no, it does not.

5. Declaration and sign-off

The plan must include:

A statement committing to Net Zero by 2050 (or earlier)
The plan's publication date
Approval at director level (signed by an appropriate company director — MD, FD, or designated board sponsor)
A link to where the plan is publicly available on your company website

The sign-off is not a formality. Procurement teams do check the named director exists on Companies House and that the date is recent.

How to build a Carbon Reduction Plan as a UK SME

For an SME with no prior emissions reporting history, the end-to-end process typically takes 4-8 weeks from start to publishable plan. The sequence:

Week 1: Data gathering

Pull 12 months of:

Electricity bills (kWh consumed, any REGO/green-tariff status)
Gas bills (kWh consumed)
Fuel card data (litres of petrol, diesel)
Company vehicle mileage logs
Business travel claims (miles/km, mode split)
Employee commuting survey (or modelled average based on headcount × UK commuting default)
Waste invoices (tonnes, diversion rate)
Water bills (m³, if material)

Week 2: Emissions calculation

Apply the 2025 UK government conversion factors to each input. The arithmetic is mechanical: activity × conversion factor = tCO₂e. Sum by scope.

Our free Carbon Footprint Estimator will get you to a defensible Scope 1 and 2 baseline in about 30 minutes of input time. Scope 3 typically needs a spreadsheet given the diverse category data.

Week 3: Narrative sections

Write the four non-numeric sections:

Commitment statement (Net Zero by 2050 or earlier)
Baseline year emissions summary
Emissions reduction targets
Carbon reduction projects (specific, verifiable)

The PPN 06/21 published template is ~4 pages. Most supplier CRPs end up 6-10 pages once they include detail and evidence.

Week 4: Director sign-off, publication, and tender embed

Circulate to the board/MD for sign-off. Publish on your website at a stable URL (most suppliers use /carbon-reduction-plan.pdf or /sustainability/carbon-reduction-plan). Include the URL in the selection-stage response on the tender.

Annual refresh

Each year:

Recalculate current-year emissions
Update progress-against-target
Add any new reduction projects
Refresh the publication date and director sign-off
Re-publish at the same URL (avoid breaking links from prior tender submissions)

Common reasons a CRP fails the PPN 06/21 check

Missing Net Zero by 2050 commitment statement — the wording must be explicit, not implied.
Scope 3 not covering the PPN-required subset — some suppliers cover only business travel; commuting and upstream/downstream transport must also be included at minimum.
No current-year number alongside the baseline — only reporting the baseline year is not sufficient after year one.
Unsigned or signed by someone not an appropriate director — "signed by the sustainability manager" is not sufficient.
Not publicly accessible on the company website — an internal document shared by email does not satisfy the publication requirement.
Using non-UK conversion factors — DEFRA's annual conversion factor set is the expected source for UK-reporting organisations.
Generic reduction projects — "we plan to be more efficient" is not a project. Named actions with dates and measurable impact are.

How a Carbon Reduction Plan relates to other UK sustainability reporting

A PPN 06/21 CRP is narrower than — but informs — the wider UK regulatory stack:

Regime	What it is	Who files	Overlap with CRP
SECR	Mandatory energy and carbon report in Directors' Report	Large UK companies, unquoted groups above thresholds	SECR Scope 1+2 data is re-usable in CRP
ESOS Phase 3	Mandatory energy audits for large undertakings	UK organisations above 250 staff or above turnover/balance sheet thresholds	ESOS audit evidence supports CRP reduction projects
CDP Supply Chain	Voluntary customer-driven disclosure	Suppliers of CDP Supply Chain member companies	CRP emissions baseline feeds directly into CDP Supply Chain questionnaire
CSRD / ESRS	EU sustainability reporting for in-scope entities	Large EU-listed entities and their supply chains	CSRD Omnibus 2026 narrowed the scope materially

For most UK SMEs, doing the PPN 06/21 emissions baseline work is 60-70% of the effort of CDP Supply Chain, EcoVadis, and any bank sustainability-linked loan questionnaire you will ever receive. Building it once and reusing the facts across every questionnaire format is the high-leverage move — see our guide on how to build an ESG fact vault from scratch.

PPN 06/21-aligned template

A complete PPN 06/21-aligned Carbon Reduction Plan includes the five mandatory sections above, structured consistently across every annual refresh. The PPN 06/21 gov.uk page links to an official template suppliers may use as a starting point. Many large primes also publish their own preferred CRP formats — check with your customer's procurement portal.

In AnswerVault's structured fact vault, the emissions baseline, reduction targets, reduction projects, and director commitment are each stored as separate reusable facts. When the CRP is due each year, the data refreshes in one place and the template assembles from the current facts — without retyping numbers into a new document.

FAQ

Is PPN 06/21 a law? No — it is a Procurement Policy Note, not statute. Compliance is enforced through procurement eligibility rules. The legal framework it sits under is the Procurement Act 2023.

Does PPN 06/21 apply to subcontractors? The policy technically applies to the prime contractor bidding for the contract. In practice, many primes now cascade CRP requirements to their first-tier subcontractors on large contracts. If you are a subcontractor, check your prime's flow-down clauses.

How often do I need to update the plan? Annually. An out-of-date CRP on your website is a fail criterion — some procurement teams check the publication date matches the current reporting year.

What if we cannot calculate our Scope 3? PPN 06/21 only requires a subset of Scope 3. Business travel and commuting are the categories most suppliers worry about; both can be modelled from HR data and the UK government conversion factors. The full upstream/downstream breakdown is not required.

Can I use an external consultant to write it? Yes. Many SMEs commission a specialist to write the first plan (typical cost £2,500-£8,000) and then maintain it in-house. The director sign-off and company responsibility are non-delegable — the plan is your company's, regardless of who drafted it.

Is the CRP the same as a Net Zero plan? Not quite. A Carbon Reduction Plan under PPN 06/21 requires a Net Zero by 2050 commitment as one element, but a full net zero plan (as investors or the SBTi might assess) is broader. The PPN 06/21 CRP is the minimum floor; a net zero plan can exceed it.

The takeaway for UK SME sustainability leads

PPN 06/21 is triggered by bidding on central government contracts over £5M
The plan has five mandatory sections — miss any and the tender fails
The underlying emissions calculation work is the same work you need for SECR, CDP, EcoVadis, and every supplier ESG questionnaire
Use the UK government conversion factors — they are the accepted default
Build once, reuse across every sustainability questionnaire you answer

AnswerVault stores your emissions baseline, reduction targets, reduction projects, and director sign-off statement once in a structured vault. When the next CDP questionnaire, EcoVadis assessment, or sustainability-linked loan questionnaire arrives, the facts are already there — the work is reviewing, not rewriting. Start a 14-day free trial to see how.

Sources

Procurement Policy Note 06/21 — gov.uk
Procurement Act 2023
UK government greenhouse gas conversion factors
Greenhouse Gas Protocol Corporate Standard
UK Government: Measuring and reporting environmental impacts
Science Based Targets initiative
This article provides general guidance for UK SMEs bidding on UK government contracts. It is not legal advice on procurement compliance. PPN 06/21 is periodically updated — always check the current version on gov.uk before finalising a tender response.