GHG Protocol · the greenhouse gas reporting framework
The GHG Protocol: which edition, which rule
The GHG Protocol is the greenhouse gas reporting framework most corporate inventories are built on, and UK SRS S2 ¶29(a)(ii) names its 2004 Corporate Standard as the measurement basis.
It is a suite, not a single document: a 2004 standard amended in 2013 and 2015, a 2011 scope 3 standard, and guidance that explains without adding requirements.
A consolidated revision with ISO is under way, with a published standard estimated for the fourth quarter of 2028.
The basics
What the GHG Protocol is, and who owns it
The Greenhouse Gas Protocol publishes standards, guidance and tools for measuring greenhouse gas emissions, and was developed by the World Resources Institute and the World Business Council for Sustainable Development.
Its Corporate Accounting and Reporting Standard sets the requirements for a company-level inventory: the boundary, the three scopes, and what must be reported.
The standard is policy-neutral: it does not require anyone to report to the World Resources Institute or the WBCSD, and it carries no legal force of its own in the UK.
It becomes a requirement only when another instrument points at it — UK SRS S2, the SBTi’s criteria, or a contract.
Plain-English definitions of each scope, with examples, are on our scope 1, 2 and 3 emissions page.
The Corporate Standard “should not be used to quantify the reductions associated with GHG mitigation projects for use as offsets or credits”.
The suite, document by document
Which GHG Protocol documents are in force
The GHG Protocol’s standards and guidance list mixes standards, amendments and guidance. This register labels each one.
Filter by family or search.
GHG Protocol documents
Showing 8 of 8
| Document | Edition | Status on 1 October 2026 | What it does |
|---|---|---|---|
| Corporate Accounting and Reporting Standard | Revised Edition, March 2004 | In force | Scopes 1 and 2 required; scope 3 optional under this standard alone |
| Required gases and GWP values (amendment) | February 2013 | In force | Adds nitrogen trifluoride: seven gases |
| Scope 2 Guidance (amendment to the Corporate Standard) | 2015 | In force | Location-based and market-based methods; dual reporting where instruments exist |
| Corporate Value Chain (Scope 3) Standard | 2011, corrected 2013 | In force | All fifteen categories; exclusions disclosed and justified |
| Technical Guidance for Calculating Scope 3 Emissions | 2013 (category 4 October 2013) | Guidance | Calculation methods by category; creates no requirements |
| Product Life Cycle Accounting and Reporting Standard | Developed alongside the Scope 3 Standard | In force; joint ISO working group named February 2026 | Emissions of a single product across its life cycle |
| Land Sector and Removals Standard and Guidance | 2026 | Published | Land emissions and CO2 removals |
| Consolidated corporate standard (with ISO 14064-1) | Draft estimated Q2 2027; publication estimated Q4 2028 | In development | Will replace the corporate suite; title not yet fixed |
Sources: GHG Protocol Corporate Standard, Scope 3 Standard, Scope 3 calculation guidance and Product Standard pages; SDP v2.0 (29 July 2026).
The trap is treating the Corporate Standard as one 2004 document.
The 2004 PDF lists six gases; the GHG Protocol’s own page now says seven, because nitrogen trifluoride was added by the 2013 amendment, and it says the standard “was updated in 2015 with the Scope 2 Guidance”.
So the operative text is the 2004 standard plus its amendments, and a citation should name both.
The scope 3 calculation guidance is a companion: it describes methods and can point at the standard’s requirements, but it cannot create new ones.
The Product Standard works at product level, which our page on life cycle assessment and product standards sets beside ISO 14067 and PAS 2050.
Chapter 1
The five principles of GHG accounting
| Principle | Corporate Standard, chapter 1 |
|---|---|
| Relevance | “Ensure the GHG inventory appropriately reflects the GHG emissions of the company and serves the decision-making needs of users – both internal and external to the company.” |
| Completeness | “Account for and report on all GHG emission sources and activities within the chosen inventory boundary. Disclose and justify any specific exclusions.” |
| Consistency | “Use consistent methodologies to allow for meaningful comparisons of emissions over time. Transparently document any changes to the data, inventory boundary, methods, or any other relevant factors in the time series.” |
| Transparency | “Address all relevant issues in a factual and coherent manner, based on a clear audit trail. Disclose any relevant assumptions and make appropriate references to the accounting and calculation methodologies and data sources used.” |
| Accuracy | “Ensure that the quantification of GHG emissions is systematically neither over nor under actual emissions, as far as can be judged, and that uncertainties are reduced as far as practicable.” |
Chapter 1 says GHG accounting and reporting “shall be based on” these principles, and their main job is to settle questions the detailed rules leave open.
Completeness does the most practical work: the chapter says a minimum accounting threshold that lets small sources drop out is not compatible with it, because quantifying a source to prove it is small removes most of the benefit of the threshold.
The SBTi takes the same line, refusing “negligible” as a reason to leave a source out, in footnote 9 to its near-term criteria.
Transparency is what makes an inventory verifiable, which is the subject of our page on GHG verification standards.
The GHG Protocol’s December 2025 progress update shows working-draft revisions to the principles’ guidance; those are proposals, and the 2004 text above is what applies.
Organisational boundary
Equity share or control, and what it brings in
Before any scope is counted, the Corporate Standard asks a company to choose how it consolidates emissions from operations it does not wholly own.
It offers three approaches: equity share, financial control and operational control.
The choice decides which joint ventures, leased assets and franchises fall in scopes 1 and 2 and which drop to scope 3.
The SBTi requires targets at parent or group level, including every subsidiary inside the chosen approach, and treats a change of approach as a recalculation trigger.
The choice also has to be held steady: the Corporate Standard’s consistency principle asks for any change to the inventory boundary to be documented and justified.
The checker applies the standard’s chapter 3 to one relationship at a time; how carbon software handles the same choice is on our carbon accounting software guide.
Boundary checker · Chapter 3 and ¶29(a)(iv)
Scope 2
Location-based, market-based, and the UK difference
The 2015 Scope 2 Guidance gives two methods: location-based, using average grid factors, and market-based, using the contractual instruments a company holds.
Where a company operates in markets that offer such instruments, the guidance requires it to report both.
The guidance warns that the two totals “should not be viewed as ‘gross/net’”, because a net figure implies offsets have been applied.
UK SRS S2 goes another way: ¶29(a)(v) and ¶B30 require location-based scope 2 and information about contractual instruments where it informs users, and ¶B31 makes market-based figures optional.
So a company can comply with UK SRS S2 with a single location-based figure, and a company following the GHG Protocol in full reports both.
The SBTi’s V2.0 standard also sets targets on the location-based inventory; the methods are compared on our scope 2 emissions page.
The scope 2 revision is in progress: its public consultation drew low support for hourly matching as proposed, and the GHG Protocol’s board called for further work, according to the July 2026 feedback summary; nothing has changed for reporters yet.
Scope 3, three ways
Three instruments, three answers on scope 3
| Instrument | Scope 3 status | Provision |
|---|---|---|
| GHG Protocol Corporate Standard (2004) alone | Optional | Chapter 4: “an optional reporting category”; chapter 9 requires scope 1 and 2 at minimum |
| Plus the Scope 3 Standard (2011) | All fifteen categories; exclusions disclosed and justified | §6.2: “Companies shall account for all scope 3 emissions … and disclose and justify any exclusions” |
| UK SRS S2 | Gross scope 3 required; all fifteen categories considered; the included ones disclosed | ¶29(a)(i)(3), ¶B32, ¶B33; ¶C4 relief has no time limit |
No scope 3 category is optional under the Scope 3 Standard: the word “optional” in §6.2 attaches to activities beyond a category’s minimum boundary.
A category that does not apply is reported as zero or not applicable.
UK SRS S2 asks an entity to consider all fifteen and disclose which it includes, which is not the same as reporting all fifteen.
Under the FCA’s final rules, listed companies have a one-year relief from disclosing scope 3 under UK SRS S2, during which they state that they are using it.
The categories are explained on our scope 3 emissions page, the UK SRS rules on UK SRS scope 3 reporting, and a category-by-category implementation guide on srsreport.co.uk.
UK reporting
How the GHG Protocol threads into UK SRS S2
UK SRS S1 and S2 were published by the Department for Business and Trade on 25 February 2026, as the government’s publication page records.
UK SRS S2 ¶29(a)(ii) names the 2004 Corporate Standard, a fixed edition rather than “the current GHG Protocol”.
Whether that reference carries the 2013 gases amendment and the 2015 Scope 2 Guidance is not addressed in the standard, and we do not assert either reading.
The same sentence carries a carve-out: a jurisdictional authority or exchange can require a different method.
The FCA’s final rules, PS26/19, have listed companies in UKLR 6, 14, 15, 16 and 22 report against UK SRS on a comply-or-explain basis for periods beginning on or after 1 January 2027, so for them ¶29 is the text they comply with or explain against.
What comply or explain requires is set out on UK SRS compliance; how the old TCFD-aligned rules map across is on TCFD and UK SRS.
Targets disclosed under ¶¶33–36 sit on the same inventory, and the UK SRS position on climate plans covers what a listed company says about a plan.
| UK SRS S2 | What it says |
|---|---|
| ¶29(a)(i) | Absolute gross scope 1, 2 and 3 emissions in tonnes CO2e |
| ¶29(a)(ii) | Measured under the GHG Protocol Corporate Standard (2004), unless an authority or exchange requires another method |
| ¶C3 | Another method allowed in the first reporting period only |
| ¶C4 | Scope 3 need not be disclosed; no time limit in the standard |
| ¶29A | Category 15 may be limited to financed emissions; derivatives may be excluded |
UK conversion factors
Turning activity data into emissions: the DESNZ factors
The GHG Protocol tells a company what to count; in the UK most companies turn litres and kilowatt-hours into tonnes with the government’s GHG conversion factors, published each year by DESNZ.
DESNZ frames the factors as relevant to the Environmental Reporting Guidelines, including SECR, and says other uses are at the user’s own risk.
The rule people miss is the year: the 2026 methodology paper says the 2026 factors are for activity data that falls entirely or mostly within 2026.
The 2026 set also changed how the electricity factor is calculated, cutting the lag in its data from two years to one, so there is no 2024 data year and the 2025-to-2026 fall mixes grid change with method change, as the major changes report records.
A year-on-year scope 2 comparison spanning 2025 and 2026 should say so, and a comparison with an older year should use that year’s set, such as the 2024 factors.
SECR reports name the methodology too, as the Environmental Reporting Guidelines explain; our pages on UK carbon reporting and carbon reporting software cover the disclosure and the systems that hold each year’s set.
| Rule | Source |
|---|---|
| Match the factor year to the activity-data year, not the publication or filing year | Methodology paper ¶1.10 |
| FY2026 reported in 2027 uses the 2026 set | ¶1.10 |
| 2026 electricity factor reflects a method change; no 2024 data year | ¶1.13; Table 7 footnote |
| Scope 2 on the generated factor; T&D losses in scope 3 category 3 | ¶3.1 |
| CH4 and N2O on IPCC AR5 GWPs | ¶1.9 |
The revision
What is changing, and when
The GHG Protocol is revising its whole corporate suite, and since 29 July 2026 the plan is a single standard rather than four revised documents.
The standard development plan brings the Scope 1, 2 and 3 standards and the actions and market instruments work together with ISO 14064-1, and expects to publish in parts, with guidance to follow later.
Its estimates are a consolidated draft for public consultation in the second quarter of 2027 and a published revised standard in the fourth quarter of 2028, and it says the timeline may change.
The second quarter of 2027 is a consultation date, not a publication date.
The partnership with ISO dates from 9 September 2025, and the partnership FAQ is clear that both bodies keep full authority over their own standards and governance.
The GHG Protocol’s July 2026 announcement and the earlier scope 2 board decision of August 2025 set out how the consultations fed the plan.
Until GHG Protocol communicates otherwise, its update-process page says, the existing standards and guidance stay in effect, and UK SRS S2’s 2004 reference stays where it is.
ISO’s own organisation-level standard, ISO 14064-1:2018, is also flagged for revision, which is part of the same consolidation.
- 9 Sep 2025GHG Protocol–ISO partnership announced
- 20 Oct 2025 – 31 Jan 2026Two public consultations
Scope 2 Guidance updates and consequential methods; nearly 1,100 responses.
- 31 Mar – 31 May 2026Actions and market instruments
Request for information and feedback.
- 29 Jul 2026Consolidated plan published
One co-branded standard with ISO.
- Est. Q2 2027Consultation draft
- Est. Q4 2028Revised standard published
Is it mandatory?
Where the GHG Protocol becomes a requirement
| Regime | Does it require the GHG Protocol? | Status of the regime |
|---|---|---|
| UK SRS S2 | Yes: the 2004 Corporate Standard, unless an authority or exchange requires another method (¶29(a)(ii)) | Voluntary; comply or explain for listed companies in five categories from 2027 |
| SBTi near-term and net-zero criteria | Yes: Corporate Standard, Scope 2 Guidance and Scope 3 Standard | Voluntary |
| SECR | No method prescribed; the report must state the methodologies used (Sch 7 ¶16, ¶20F) | Mandatory for companies in scope |
| PPN 006 carbon reduction plans | Built on the GHG Protocol scopes, with a five-category subset of scope 3 | A procurement condition |
| Customer and lender requests | Usually, by contract | Contractual |
The wider picture of which UK regimes ask for emissions at all is on our UK sustainability reporting overview.
Where a figure must be checked by someone else, the standard is not the GHG Protocol: the Corporate Standard says it does not provide a standard for how verification should be conducted, and our sustainability assurance guide covers the assurance side.
Test yourself
Six GHG Protocol claims, true or false
The errors that recur in UK reports are about editions and words.
The 2004 edition is not “the latest”, “optional” in the Scope 3 Standard does not mean a whole category, and market-based scope 2 is not a net figure.
Each answer names the paragraph that settles it.
GHG Protocol: true or false?
UK SRS S2 points at whatever the latest GHG Protocol Corporate Standard is.
Under the Scope 3 Standard some categories are optional.
Location-based and market-based scope 2 are gross and net figures.
A company reporting FY2026 in spring 2027 should use the 2026 DESNZ factors.
ISO has taken over the GHG Protocol.
A completeness threshold that omits small sources is compatible with the Corporate Standard.
0 of 6 answered.
Nothing you choose is stored or sent.
Frequently asked
GHG Protocol questions, answered
What is the GHG Protocol?
The Greenhouse Gas Protocol is a set of standards for measuring and reporting greenhouse gas emissions, developed by the World Resources Institute and the World Business Council for Sustainable Development.
Its Corporate Accounting and Reporting Standard, revised in March 2004, defines scopes 1, 2 and 3 and is the basis for the SBTi, UK SRS S2 and most corporate inventories.
Is the GHG Protocol mandatory in the UK?
Not in itself: it is a voluntary standard. It becomes the measurement basis where another instrument points at it.
UK SRS S2 paragraph 29(a)(ii) requires measurement in accordance with the 2004 Corporate Standard unless a jurisdictional authority or exchange requires another method, and listed companies in five UK Listing Rules categories report against UK SRS on a comply-or-explain basis from 2027.
The SBTi also requires it.
What are scope 1, 2 and 3 emissions in the GHG Protocol?
Scope 1 is direct emissions from sources a company owns or controls.
Scope 2 is indirect emissions from the generation of purchased electricity, steam, heat and cooling it consumes.
Scope 3 is all other indirect emissions across the value chain, in fifteen categories under the 2011 Scope 3 Standard.
What are the seven greenhouse gases?
Carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride and nitrogen trifluoride.
The 2004 Corporate Standard listed the first six Kyoto gases; nitrogen trifluoride was added by a 2013 amendment, and the GHG Protocol’s own page now describes the standard as covering seven.
What are the five principles of GHG accounting?
Relevance, completeness, consistency, transparency and accuracy.
Chapter 1 of the Corporate Standard says GHG accounting and reporting shall be based on them, for example completeness: account for and report on all emission sources and activities within the chosen inventory boundary, and disclose and justify any specific exclusions.
Does UK SRS require the GHG Protocol?
UK SRS S2 paragraph 29(a)(ii) requires an entity to measure its emissions in accordance with the GHG Protocol Corporate Standard (2004), unless a jurisdictional authority or an exchange on which it is listed requires a different method.
Paragraph C3 lets an entity use another method in its first reporting period only.
UK SRS is voluntary unless the FCA’s rules apply.
Does UK SRS S2 require dual scope 2 reporting?
No. UK SRS S2 requires location-based scope 2 and information about contractual instruments where they inform users; market-based figures are permitted, not required.
The GHG Protocol’s 2015 Scope 2 Guidance requires both methods where a company operates in markets with contractual instruments.
Which UK conversion factors should be used?
Most UK reporters use the government GHG conversion factors published by DESNZ.
The factor year should match the activity-data year: the 2026 methodology paper says the 2026 factors are for activity data that falls entirely or mostly within 2026.
The 2026 electricity factor also reflects a methodology change, so a 2025-to-2026 scope 2 comparison should say so.
Is the GHG Protocol being revised?
Yes.
GHG Protocol and ISO are consolidating the Corporate Standard, Scope 2 Guidance, Scope 3 Standard, the Actions and Market Instruments work and ISO 14064-1 into a single standard.
The development plan of 29 July 2026 estimates a consolidated draft for public consultation in the second quarter of 2027 and a published revised standard in the fourth quarter of 2028.
The existing standards stay in effect until then.
Does the GHG Protocol tell you how to verify an inventory?
No. The Corporate Standard is designed to produce a verifiable inventory, but its own page says it does not provide a standard for how verification should be conducted.
Verification uses other standards, such as ISO 14064-3 for GHG statements.
Sources
Primary sources
Every figure, date and status on this page traces to the instrument’s owner.
Secondary commentary is never the source for a number.
- GHG ProtocolA Corporate Accounting and Reporting Standard, Revised Edition (March 2004)
Scopes, boundaries and required reporting; the seven gases and the 2015 Scope 2 update on the landing page.
- World Resources InstituteGHG Protocol Corporate Standard, chapter 1: GHG accounting and reporting principles
The five principles, quoted.
- GHG ProtocolCorporate Value Chain (Scope 3) Standard (2011), Table 5.4, §6.2
All fifteen categories, exclusions disclosed and justified.
- GHG ProtocolTechnical Guidance for Calculating Scope 3 Emissions
A companion guide: methods, not requirements.
- GHG ProtocolScope 2 Guidance (2015)
Dual reporting where contractual instruments exist.
- GHG ProtocolConsolidated Corporate Standard — Standard Development Plan v2.0 (29 July 2026), §§2, 6, 9
Consultation estimated Q2 2027; revised standard estimated Q4 2028.
- GHG ProtocolCorporate suite of standards and guidance: update process
“Until Greenhouse Gas Protocol communicates otherwise, the existing … standards and guidance stay in effect.”
- GHG ProtocolISO–GHG Protocol partnership: frequently asked questions
Both bodies keep full authority over their own standards.
- GHG ProtocolScope 2 public consultation: executive summary of feedback (29 July 2026)
Low support for hourly matching as proposed; further work called for.
- Department for Business and TradeUK SRS S2 Climate-related Disclosures, ¶¶29(a), 29A, B30–B33, C3–C4
The 2004 edition, gross emissions, location-based scope 2 and the scope 3 rules.
- Financial Conduct AuthorityPS26/19: final rules on UK SRS for listed issuers
Comply or explain for UKLR 6, 14, 15, 16 and 22 from 2027.
- Department for Energy Security and Net Zero2026 GHG conversion factors methodology paper, ¶¶1.9–1.10, 1.13, 3.1
Factor year matches activity year; the 2026 electricity method change.
- Department for Energy Security and Net ZeroGovernment conversion factors for company reporting (collection)
The annual sets; for use with the Environmental Reporting Guidelines including SECR.
- Defra and DESNZEnvironmental Reporting Guidelines including SECR guidance (March 2019)
The SECR methodology statement.