Required
UK ETS: a verified emissions report from a verifier accredited to ISO 14065 and the Verification Regulation.
Its own regime, not ISO 14064 as such.Greenhouse gases · ISO standards
ISO 14064
ISO 14064 is ISO’s series for counting greenhouse gas emissions and checking the count: Part 1 for an organisation, Part 2 for projects, Part 3 for verification.
No UK law requires it, and verifying to it gives you a verifier’s opinion, not a certificate.
The UK ETS is the one UK regime here that requires an accredited verifier, under its own regulation.
The parts
What is ISO 14064?
Five documents: three standards that set requirements, two that give guidance, with two companions for the verifiers.
| Document | What it covers | Status |
|---|---|---|
| ISO 14064-1:2018 | An organisation’s greenhouse gas inventory: quantifying and reporting emissions and removals | Current, marked “to be revised”; a working draft is in progress (ISO) |
| ISO 14064-2:2019 | Projects intended to reduce emissions or enhance removals | Current (ISO) |
| ISO 14064-3:2019 | Verifying and validating GHG statements for organisations, projects and products | Current, confirmed in 2024 (ISO) |
| ISO/TS 14064-4:2025 | Guidance on applying ISO 14064-1; replaced ISO/TR 14069 | Technical Specification, November 2025 (ISO) |
| ISO 14064-5:2026 | Guidance on verifying and validating remotely | Guidance, February 2026 (ISO) |
| ISO 14065:2020 | Requirements for the bodies that validate and verify environmental information | Confirmed in 2026 (ISO) |
| ISO 14066:2023 | Competence of validation and verification teams and independent reviewers | Current (ISO) |
ISO calls the series “GHG programme neutral”: where a scheme such as the UK ETS applies, its rules come first (ISO 14064-1).
Part 1 sorts indirect emissions into five categories rather than the GHG Protocol’s Scopes 2 and 3; how a company counts its footprint is explained on GHG accounting.
No amendment to ISO 14064-1 has been published: the 2024 climate amendments went to management-system standards such as ISO 14001 and ISO 50001 (ISO).
Status
Is ISO 14064 mandatory in the UK?
No. One regime requires accredited verification, others ask for none, and buyers and regulators may point to it.
No UK law requires a company to obtain sustainability assurance, and SECR’s guidance says there is “no statutory requirement to have your environmental information audited” (SECR guidance).
PPN 006 asks for a footprint “conducted to a reasonable level of assurance” and then says “there is no requirement to have your carbon footprint audited” (PPN 006 ¶18).
Read together, that is a quality expectation on the bidder’s own work, not a demand for external verification; the plan rules are on carbon reduction plans.
From periods beginning on 1 January 2027, a listed company in scope of the FCA’s rules states whether it obtained assurance and, if it did, the provider, scope, level and standard (PS26/19, UKLR 6.6.6R(8)(d)).
A UK rule and verified GHG figures
Not required
SECR, PPN 006 carbon reduction plans, and UK SRS for listed companies, which say whether they obtained assurance.
Voluntary verification is still allowed.Pointed to
Ofwat expects water companies to use frameworks “such as … ISO14064”.
An expectation, not a licence condition.Certification
Is there such a thing as ISO 14064 certification?
Not as there is for ISO 14001: verification to ISO 14064-3 ends in a verifier’s opinion on your GHG statement.
UKAS lists GHG verification among its validation and verification schemes, and not among the management-system certifications such as ISO 14001 and ISO 50001 (UKAS).
Some verifiers call what they issue a statement or a certificate; ISO 14064-3’s own word is opinion.
An opinion covers the statement it names, for the period it names, not the company in general.
Who does whatExplore
Who does what
The verifier
Checks the GHG statement and issues an opinion, at the level agreed beforehand.
Who does what
UKAS
Accredits GHG verifiers under its validation and verification programme, separately from certification bodies.
One company
What does this mean for one manufacturer?
A manufacturer with a UK ETS installation that also bids for government work needs one verification by law and can choose others.
It is an illustration, not a real company.
Without the installation it would need no verification at all, though a customer or investor might still ask.
If it were listed in one of the FCA’s five categories, its annual report would say whether its figures were assured.
- 1
Its UK ETS installation
Needs a verified emissions report from a verifier accredited by UKAS to ISO 14065 and the Verification Regulation (GOV.UK).
- 2
Its SECR disclosure
Needs no assurance at all (SECR guidance).
- 3
Its carbon reduction plan
Has no audit requirement, but must be signed off by a director (PPN 006 ¶¶18, 25).
- 4
Its choice
It may still have its company footprint verified to ISO 14064-3, at a level agreed before the work (ISO).
- 5
What it gets
A verifier’s opinion on the statement, not a certificate (UKAS).
What each rule asks
What does each UK rule ask for, regime by regime?
A verified report for the UK ETS, nothing for SECR or PPN 006, and a statement of what was done for listed companies.
| Regime | Verification asked for | Source |
|---|---|---|
| UK ETS | Yes: a verified emissions report, by a verifier accredited for the activity reported | Reg (EU) 2018/2067 Art 44 (UK) |
| SECR | None: “There is no statutory requirement to have your environmental information audited” | SECR guidance |
| PPN 006 carbon reduction plan | None: “no requirement to have your carbon footprint audited”; director sign-off required | PPN 006 ¶¶18, 25 |
| UK SRS, FCA listing rules | None required; state whether assurance was obtained, and its provider, scope, level and standard | PS26/19 |
| Water companies | Ofwat expects frameworks such as ISO 14064 | Ofwat |
SECR and PPN 006 guidance still name ISAE 3410, which the IAASB withdraws when ISSA 5000 takes effect on 15 December 2026; the assurance standards are on sustainability assurance.
Verification
What does an ISO 14064-3 verifier actually do?
Checks whether your statement is materially correct, to a level of assurance agreed before the work starts.
Verification evaluates historical data to see whether a statement “is materially correct and conforms to criteria” (ISO 14064-3).
The level is fixed before the work and may not be changed during it.
The standard can be used by first-, second- and third-party verifiers, so “verified to ISO 14064-3” does not on its own mean independent.
Since February 2026, ISO 14064-5 guides remote work, but only where Part 3 does not require a site visit (ISO).
What the engagement gives
Reasonable assurance
“High but not absolute”; the body of ISO 14064-3 is written for it.
An opinion on the statement.Limited assurance
“Reduced” assurance, set out in Annex A.
An opinion, worded more narrowly.Agreed-upon procedures
Agreed checks are carried out and reported.
No opinion at all.Your check
What kind of GHG check do you need?
Say what needs checking, by whom and at what level: the part, the rule and the accreditation follow.
The answer separates what a UK rule requires from what a buyer, investor or scheme may ask for.
For a UK ETS report the rulebook is the scheme’s own, and ISO 14064 is not the test.
For anything else, an independent accredited verifier is a choice, and the level is the first thing to agree.
ISO 14064 · what kind of check do you need?
Pick what needs checking.
Rules: ISO 14064-1, -2 and -3 catalogue records; UKAS validation and verification accreditation; Regulation (EU) 2018/2067 as it has effect in the UK; SECR guidance; PPN 006 Technical Standard ¶18; FCA PS26/19.
A starting point, not advice on a particular engagement. Nothing you enter leaves your browser.
Who verifies
Who can verify to ISO 14064 in the UK?
Anyone can use the standard; for an accredited check, look for the body’s scope in the UKAS directory.
No standard-setter ranks verification bodies, so “which is the best” has no checkable answer; whether a body is accredited for the claim does.
The test is the body’s entry in the UKAS directory, with a validation and verification scope that covers your statement.
For the UK ETS, the regulator keeps a list of UKAS-accredited verifiers in METS, and the scope must cover the regulated activity (GOV.UK).
A consultant can help you prepare, but is never UKAS-accredited; what to ask before hiring is on GHG verification consultants, and the standards side by side on GHG audit.
The verifier’s credentialsExplore
The verifier’s credentials
UKAS
The UK’s sole national accreditation body; it accredits bodies, never consultants or individuals.
The verifier’s credentials
ISO/IEC 17029 with ISO 14065
The basis UKAS moved GHG verifiers to by 30 June 2024.
The verifier’s credentials
EN ISO 14065:2013
Still the edition the UK ETS Verification Regulation names for accreditation.
The verifier’s credentials
ISO 14066
Competence of the verification team and the independent reviewer.
What is changing
What is changing for ISO 14064?
Part 1 is being rewritten, and the GHG Protocol and ISO are consolidating their corporate standards.
- 30 June 202401
UKAS moves GHG verifiers to ISO/IEC 17029
Bodies accredited to ISO 14065 had to transition by this date. - 9 September 202502
GHG Protocol and ISO announce a partnership
To consolidate their corporate standards; both remain independent in their decisions. - 25 November 202503
- 12 February 202604
- 12 May 202605
- 15 December 202606
- Q2 2027 (estimate)07
Consolidated GHG Protocol standard out for consultation
Publication estimated in Q4 2028.
ISO and the GHG Protocol say they remain fully independent in their decisions; ISO gives no date for a new Part 1 (GHG Protocol).
Order of work
What should a company do first?
Find which rule asks for what, fix the boundary and method, then choose the level and the verifier.
The inventory method the UK’s listed-company standard uses is the GHG Protocol, explained on the GHG Protocol.
How accreditation works, and how to check a certificate, is on UKAS accreditation.
- 1
List who is asking
The UK ETS regulator, a buyer, an investor or your own board. - 2
Fix the inventory
Boundary, method and period, to ISO 14064-1 or the GHG Protocol. - 3
Agree the level
Reasonable or limited, before the work starts. - 4
Check the verifier’s scope
In the UKAS directory, or the METS list for the UK ETS. - 5
Say what was done
Name the standard, the level and the provider where you report.
ISO 14064-3 · UKAS · PS26/19
ISO 14064 gives you a way to count and an opinion on the count, and only the UK ETS turns that opinion into a legal duty.
- Five parts
ISO 14064 is three standards and two guidance documents
Parts 4 and 5 arrived in 2025 and 2026. - An opinion
Verification ends in a verifier’s opinion, not a certificate
ISO certifies no one. - UK ETS only
The UK ETS is the one regime here that requires accredited verification
Under its own Verification Regulation. - No audit required
PPN 006 and SECR do not require a verified footprint
Listed companies say whether they obtained assurance. - UKAS directory
The checkable test for a verifier is its accredited scope
Not a ranking, and never a consultant.
How does ISO 14064 relate to the GHG Protocol?
Separate standards for the same job, now being consolidated, with the UK’s listed-company standard naming the GHG Protocol.
ISO 14064-1 is not the UK SRS method, and it does not replace the GHG Protocol.
ISO 14064-3 can verify an inventory built either way.
Two familiesExplore
Two families
The consolidation
A consolidated corporate standard, consultation estimated Q2 2027.
Frequently asked
What else do people ask about ISO 14064?
What is ISO 14064?
ISO 14064 is ISO’s series of standards for greenhouse gas accounting and its verification.
Part 1 covers an organisation’s inventory, Part 2 projects that reduce or remove emissions, and Part 3 how a verifier checks a GHG statement.
Parts 4 and 5, published in November 2025 and February 2026, are guidance.
Is ISO 14064 mandatory in the UK?
No. No UK law requires a company to use ISO 14064.
The UK ETS requires a verified emissions report from an accredited verifier, under its own Verification Regulation.
SECR has no assurance requirement, and PPN 006 says there is no requirement to have a carbon footprint audited.
Can a company be ISO 14064 certified?
Not in the way it is certified to ISO 14001 or ISO 50001.
ISO 14064-3 verification ends in a verifier’s opinion on a GHG statement.
UKAS accredits GHG verifiers under its validation and verification programme, separately from certification bodies, and ISO itself certifies no one.
Who can verify to ISO 14064 in the UK?
Any verifier can use ISO 14064-3, including a company’s own team, so the standard alone does not mean independent.
For an accredited, independent check, look for a body in the UKAS directory whose validation and verification scope covers the claim.
For the UK ETS, the verifier must be accredited by UKAS to ISO 14065 and the Verification Regulation.
UKAS accredits bodies, never consultants.
What is the difference between ISO 14064-1 and ISO 14064-3?
ISO 14064-1 tells an organisation how to quantify and report its greenhouse gas inventory.
ISO 14064-3 tells a verifier how to check a GHG statement, whether for an organisation, a project or a product, and give an opinion on it.
Is ISO 14064 the same as the GHG Protocol?
No. They are separate standards that cover the same ground.
The GHG Protocol and ISO announced a partnership on 9 September 2025 to consolidate their corporate standards, with a consultation estimated in Q2 2027.
UK SRS S2 measures emissions with the GHG Protocol, not ISO 14064-1.
Is ISO 14064-1 being revised?
Yes.
ISO marks ISO 14064-1:2018 “to be revised”, and its successor is a working draft.
ISO gives no publication date for the new edition.
What level of assurance does ISO 14064-3 give?
Reasonable assurance, which is high but not absolute, or limited assurance, which is reduced.
The level is agreed before the work starts and is not changed during it.
Sources
Where does each figure come from?
Every figure, date and status on this page traces to the instrument’s owner.
Secondary commentary is never the source for a number.
Checked against 22 sources fromISOUKASlegislation.gov.ukGOV.UKDESNZ and DefraCabinet Office
- ISOISO 14064-1:2018, organisation-level quantification and reporting
The generic inventory standard; programme-neutral; marked “to be revised”.
- ISOISO 14064-2:2019, project-level quantification
Emission reductions and removal enhancements from projects.
- ISOISO 14064-3:2019, verification and validation of GHG statements
Organisation, project and product statements; confirmed in 2024.
- ISOISO/TS 14064-4:2025, guidance for applying ISO 14064-1
Published 25 November 2025; replaces ISO/TR 14069.
- ISOISO 14064-5:2026, guidance on remote verification and validation
Published 12 February 2026.
- ISOISO/WD 14064-1.2 (the revision of Part 1)
A working draft; comment period closed 12 May 2026.
- ISOISO 14065:2020, requirements for validation and verification bodies
Requirements for bodies that validate and verify environmental information.
- ISOISO 14066:2023, competence of validation and verification teams
Competence of teams and independent reviewers.
- ISOCertification
“ISO does not perform certification or issue certificates.”
- UKASValidation and verification body accreditation
GHG verification “e.g., according to ISO 14064-3”; the move to ISO/IEC 17029 by 30 June 2024.
- UKASCertification body accreditation
Management-system schemes; GHG verification is not among them.
- UKASFind an organisation
The directory of accredited bodies and their scopes.
- legislation.gov.ukThe Accreditation Regulations 2009 (SI 2009/3155), regulation 3
UKAS appointed as the UK national accreditation body.
- legislation.gov.ukRegulation (EU) 2018/2067 as it has effect in the UK, Arts 3(2), 44 and Annex II
UK ETS verifiers “shall be accredited”, against EN ISO 14065:2013.
- GOV.UKUK ETS for installations: how to comply
The verifier must be accredited by UKAS to ISO 14065 and the Verification Regulation.
- DESNZ and DefraEnvironmental Reporting Guidelines, including SECR guidance (March 2019)
No statutory requirement to have environmental information audited.
- Cabinet OfficePPN 006 Technical Standard, ¶¶18, 24 and 25
“There is no requirement to have your carbon footprint audited.”
- Financial Conduct AuthorityPS26/19, UKLR 6.6.6R(8)(d)
Listed companies state whether assurance was obtained, and its provider, scope, level and standard.
- Financial Reporting CouncilISSA (UK) 5000, ¶¶11 and 15
For voluntary use; effective for periods beginning on or after 15 December 2026.
- GHG ProtocolConsolidated Corporate Standard, Standard Development Plan v2.0
Consultation estimated Q2 2027 and publication Q4 2028, with ISO as partner.
- Department for Business and TradeUK SRS S2, ¶29(a)(ii)
Emissions measured with the GHG Protocol Corporate Standard.
- OfwatFinal Climate Change Principles (February 2026)
Expects frameworks “such as … ISO14064”.
Continue reading
Where to go next
Guide
GHG audit and verification
ISO 14064-3, UK ETS verification and assurance standards side by side.
Guide
GHG verification consultants
What to ask before you hire help to prepare for verification.
Guide
UKAS accreditation
How accreditation works and how to check a body or certificate.
Guide
GHG accounting
How a company’s greenhouse gas inventory is built.