VSME Calculator — EFRAG Voluntary SME Sustainability Reporting Standard

What VSME covers

VSME is a voluntary reporting standard for non-listed small and medium-sized undertakings. It is not a carbon accounting standard, not an assurance framework, and not a subset of ESRS. It is a fixed, closed list of sustainability disclosures — twenty in total, across two modules — designed so that an SME can prepare them once a year and hand the same document to every party that asks.

Who VSME is for

The standard addresses non-listed micro, small, and medium-sized undertakings. EFRAG's own framing is that a micro-undertaking may reasonably restrict itself to the Basic Module, and that small and medium undertakings will find the Comprehensive Module relevant where a lender, investor, or value-chain partner requests information beyond the Basic set. There is no size threshold that compels use of either module, because there is no compulsion in VSME at all. The standard is voluntary in the strict sense: no undertaking is required by law to apply it, and no undertaking that applies it is required to apply all of it.

What VSME does have is a shape that regulation recognises. That recognition is the whole point, and it is discussed in the next section.

Basic Module and Comprehensive Module

• 20 disclosure requirements in total — 11 Basic, 9 Comprehensive.
• 87 datapoints in this calculator's truth-set — 54 Basic, 33 Comprehensive. This is a build-side granularity, reflecting how the disclosures decompose into discrete fields; it is not an EFRAG-published count.
• 25 datapoints are computed by the engine; 62 are captured as a readiness ledger you author.

The value-chain cap — VSME as relief, not burden

The most consequential thing about VSME is not what it asks an SME to disclose. It is what it stops other parties from asking. Under the Corporate Sustainability Reporting Directive, an undertaking inside the reporting perimeter must gather information from its value chain — which means from its SME suppliers. The directive constrains what those large undertakings may demand: information from value-chain SMEs is capped, in substance, at the content of the voluntary SME standard. An SME that has prepared a VSME report has, in the ordinary case, already answered everything a CSRD reporter is entitled to ask of it.

VSME defines twenty disclosure requirements. ESRS Set 1 defines roughly eighty-four across twelve standards. The gap between those two numbers is not a gap in ambition — it is the mechanism by which a small supplier is protected from being asked to report as though it were a large one.

Counts at the datapoint level are less settled than counts at the disclosure-requirement level: secondary reproductions of EFRAG's implementation guidance disagree on the ESRS total, with figures between roughly 913 and 1,178 depending on whether voluntary and minimum-disclosure-requirement points are included. The disclosure-requirement comparison — twenty against approximately eighty-four — is drawn directly from the standards themselves and is the more defensible framing. Either way, the direction is unambiguous.

What VSME is not

Why you are being asked for this

No law obliges a non-listed SME to publish a VSME report. Yet the requests arrive, and they arrive from three directions at once. Understanding which direction a given request comes from tells you what it is safe to answer with, and where the request exceeds what the requester is entitled to.

The trickle-down mechanism

Large undertakings inside the CSRD perimeter must describe their value chain. Financial institutions must report the emissions they finance, which means the emissions of their borrowers. Public buyers increasingly attach environmental criteria to tenders. In each case, the reporting obligation sits with someone other than the SME — but the data sits with the SME, and so the request travels downward. This is not a regulatory obligation on the SME. It is a commercial one, mediated by a contract, a facility agreement, or a tender specification.

The practical consequence is that an SME faces a large number of requests, each shaped by the requester's own reporting framework rather than by any standard the SME has adopted. A bank asks for the figures its financed-emissions methodology needs. A customer asks for the figures its ESRS E1 disclosure needs. A tender asks for whatever the buying authority's procurement policy specifies. VSME's function is to be a single answer to all three.

The CSRD value-chain cap in practice

The directive limits the information a CSRD reporter may require from an SME in its value chain to the content of the voluntary standard adopted for that purpose. In practice this means an SME can respond to an over-broad request with a completed VSME report and a statement that this is the extent of the information the requester is entitled to require. Whether the requester accepts that response is a commercial question rather than a legal one — a customer may always ask for more, and an SME may always choose to provide it — but the standard gives the SME a defensible floor and a defensible ceiling in the same document.

The cap is a feature of the CSRD, not of VSME. The distinction matters because the CSRD is moving and VSME is not.

Due diligence as the second vector

Alongside reporting, the Corporate Sustainability Due Diligence Directive imposes a conduct duty on large undertakings with respect to their chains of activity. Due diligence is a different obligation from reporting: it concerns identifying, preventing, and mitigating adverse impacts rather than disclosing them. It nevertheless generates supplier information requests, and it generates them from undertakings that may not be CSRD reporters at all. An SME's VSME disclosures — particularly B2 practices and policies, B10 remuneration and training, and the Comprehensive Module's human-rights disclosures — are the natural material with which to answer them.

How the calculation works

The quantitative core of VSME is B3: energy and greenhouse gas emissions. Everything the calculator computes with an emission factor lives here. The other computed datapoints — water consumption, waste diversion, employee turnover, accident rate, gender pay gap, collective-bargaining coverage, average training hours — are arithmetic on figures you already hold, requiring no factor and no external data.

B3 energy — the four cells

Energy consumption is disclosed in megawatt-hours across four cells: renewable electricity, non-renewable electricity, renewable fuels, and non-renewable fuels. The calculator sums them to a total and derives the renewable share. These cells are an energy disclosure, not an emissions input — the engine does not multiply MWh by a factor to produce emissions. Emissions come from the separate Scope 1 and Scope 2 portfolios described below, and an undertaking will ordinarily enter the same underlying consumption twice, once as energy in MWh and once as activity data in the emissions portfolios.

B3 Scope 1 — combustion, fugitive, process

Scope 1 (tCO₂e) = Σ(stationary fuel quantity × factor) + Σ(mobile fuel quantity × factor) + Σ(refrigerant charge kg × leak fraction × GWP-100 ÷ 1,000) + manual process tCO₂e

Stationary combustion reads DEFRA fuel factors at fuels.gbr.<slug>.<unit>; mobile combustion reads mobile_combustion.<slug>.<unit>. Each line carries its own unit — kWh, litres, tonnes, cubic metres — and the factor is selected to match. Refrigerant leakage takes a charge in kilograms and a leak percentage, and multiplies by the gas's hundred-year global warming potential from gwp.<gas>.ar6_100. Process emissions that arise from chemical or physical transformation rather than combustion are entered directly as a manual tonnage, because no general factor exists for them.

B3 Scope 2 — location-based, and only location-based

Scope 2 (tCO₂e) = Σ(country electricity kWh × grid factor) ÷ 1,000 + manual district-heat tCO₂e

Each electricity line carries a country and a kilowatt-hour quantity. The engine crosswalks the two-letter country code to a three-letter one and reads grid.<iso3>.electricity.location_based. Purchased heat, steam, and cooling are entered as a manual tonnage, because district-heating factors are network-specific and no national average is meaningful.

GHG intensity — one metric, against turnover

GHG intensity = (Scope 1 + Scope 2 in kgCO₂e) ÷ turnover in EUR × 1,000, reported as kgCO₂e per €1,000

VSME §31 defines emissions intensity against turnover and defines no other intensity. The calculator emits exactly this one. Turnover in a non-euro currency is converted to euro at a rate you supply; the calculator performs no rate lookup and stamps no conversion date. Where a counterparty asks for emissions per employee or per unit of production, that number is a derivation of your own — it is neither an engine output nor a VSME datapoint, and it should be presented as such rather than implied to carry the standard's authority.

Scope 3 is out of the Basic Module

The single most common misconception about VSME is that its greenhouse gas disclosure resembles a conventional corporate inventory. It does not. VSME §50–53 place value-chain emissions outside the Basic Module, treating them as contextual information and, where an undertaking elects to disclose them, a matter for the Comprehensive Module. This calculator computes no Scope 3 figure by any method. B3's greenhouse gas total is the sum of Scope 1 and Scope 2, and the number the calculator reports as its headline result is that sum.

An SME asked separately for a value-chain figure — by a bank applying a financed-emissions methodology, for instance, or by a customer building its own Category 1 inventory — is being asked for something VSME does not contain. That is a legitimate ask, but it is a different ask, and it should be answered with a different tool: the Scope 3 Category 1 spend-based calculator is the usual starting point. Do not enter a Scope 3 estimate into this calculator's Scope 1 or Scope 2 fields to make it appear.

Twenty-five computed, sixty-two captured

The calculator holds all 87 datapoints, but it does arithmetic on only 25 of them. Four require MasterBrain factors — Scope 1 stationary combustion, Scope 1 mobile combustion, Scope 1 fugitive refrigerant, and Scope 2 electricity. Fifteen are derived key performance indicators computed from figures you enter directly: greenhouse gas intensity, employee turnover rate, accident rate, gender pay gap, collective-bargaining coverage, average training hours, target progress, management and governance gender ratios, water consumption, and waste diversion. The remainder are sums and shares. Everything else — every narrative disclosure, every policy description, every geolocation and certification list — is captured as a status ledger, marked Draft, Ready, or Not Applicable, and authored by you.

This division is the honest description of what a calculator can do for a sustainability report. Roughly three in ten datapoints are arithmetic, and a tool can settle them. Seven in ten are judgement, description, and disclosure of practice, and no tool can write them for you. The readiness score exists to tell you how far through the second group you have travelled.

Basic Module — the disclosure inventory

Eleven disclosure requirements, decomposing into 54 datapoints. The table below states, for each, what the disclosure asks and whether the calculator computes it or holds it in the readiness ledger.

Conditional datapoints and the readiness denominator

VSME §13 distinguishes datapoints that always apply from those that apply only if a condition is met. B4 pollution applies where the undertaking is legally required to report emissions to a pollutant register. B6 discharge applies where the undertaking is water-intensive. B5 land use applies where the undertaking holds sites in or near sensitive areas. The readiness score counts a conditional datapoint in its denominator only once the triggering condition is present. An undertaking that is not water-intensive is not penalised for leaving the discharge field empty, and its readiness percentage is not depressed by a disclosure it was never required to make.

Comprehensive Module — what changes

Nine disclosure requirements, thirty-three datapoints. The Comprehensive Module adds to the Basic Module rather than deepening it: an undertaking electing the Comprehensive Module completes the Basic Module in full and then completes C1 to C9 on top. The calculator exposes both through a segmented control, and computes three of the nine.

When to volunteer the Comprehensive Module

The Basic Module answers the value-chain request. The Comprehensive Module answers the financing request. Lenders assessing transition risk want C3 targets and C4 climate risk; investors want C1 strategy and C8 sector revenues; large customers running human-rights due diligence want C6 and C7. The practical rule is to complete the Basic Module annually as a matter of course, and to add Comprehensive disclosures when a named counterparty has asked for something specific — rather than pre-emptively, in the hope of anticipating what somebody might one day want.

Emission factors and the data path

Four datapoints in VSME require an emission factor. Every other computed figure is arithmetic on data the undertaking already holds. This is a small factor surface by the standards of corporate carbon accounting, and it is small deliberately: VSME asks for the emissions an SME can actually measure from its own meters, invoices, and maintenance records.

The four MasterBrain reads

DEFRA 2026 for fuels and UK grid; Ember 2025 for non-UK grid; IPCC AR6 for refrigerants

Fuel factors, stationary and mobile, come from the UK Department for Environment, Food and Rural Affairs conversion factors, 2026 vintage. United Kingdom electricity uses the DEFRA 2026 grid average, currently 0.13096 kg CO₂e per kilowatt-hour. United States electricity uses the EPA eGRID 2023 national average, 0.349667 kg CO₂e per kilowatt-hour. Every other country resolves against Ember's Yearly Electricity Data, 2025 release. Refrigerant global warming potentials are IPCC AR6 hundred-year values.

Calculated and estimated — the confidence tier

Every computed emissions value carries an automatically derived confidence tier. A value reached by multiplying activity data by a factor is marked calculated. A value entered directly as a tonnage — process emissions, district heat, or any figure an undertaking has taken from elsewhere — is marked estimated. The tier is not a judgement about accuracy; a well-sourced manual tonnage may be more accurate than a poorly-metered activity figure. It is a statement about provenance, and it is what a reviewer will trace.

Readiness score — mandatory, triggered, and the §13 denominator

The readiness score is the number of mandatory datapoints marked Ready divided by the number of mandatory datapoints triggered. Computed datapoints become Ready automatically once their inputs are complete. Ledger datapoints are marked by you. Conditional datapoints — those VSME §13 makes applicable only where a condition holds — enter the denominator only when the condition is present. A readiness score is therefore a measure of progress against the disclosures this undertaking must actually make, not against an abstract maximum.

Activity data, not spend

There is no spend-based estimation path in this calculator, and there is none in VSME. Emissions are computed from physical activity — kilowatt-hours, litres, kilograms of refrigerant — or not at all. Where an undertaking cannot supply activity data for a source, the source is either entered as a manual tonnage from an external estimate, marked estimated, or omitted and disclosed as omitted. Spend-based factors are a value-chain tool, applied to Scope 3 categories that VSME's Basic Module does not contain. Their absence here is a consequence of the standard's boundary, not a limitation of the engine.

Countries with no MasterBrain grid row

Every country the calculator is likely to encounter — the United Kingdom, the United States, the twenty-seven member states, and the major economies covered by Ember — resolves to a live, cited grid factor. A small number of countries have no MasterBrain row. For these, the engine falls back to a hardcoded constant and surfaces a warning reading "no factor in MasterBrain — approximate". A figure carrying that warning is a screening estimate. Disclose it as such, or source a national factor and enter the resulting emissions as a manual tonnage.

Worked example — a 40-employee manufacturer

This example is the calculator's built-in default. Load the page, click calculate, and these figures appear without entering anything. Reporting currency is euro. The undertaking is a forty-employee manufacturer with a single United Kingdom site, a gas-fired process, and grid-supplied electricity. It elects the Basic Module.

Inputs

Outputs

Reading the result

Two features of this portfolio are worth drawing out. The first is that Scope 1 dominates — natural gas combustion contributes seventy per cent of the total, against thirty per cent from purchased electricity. This is characteristic of a manufacturer with a thermal process on a decarbonising grid: the United Kingdom grid factor has fallen far enough that an undertaking's own boiler now outweighs its meter. An SME reading its own result and finding this pattern has learned where its abatement lies.

The second is the readiness score. Sixty-three per cent, nineteen of thirty mandatory datapoints Ready, is what a complete quantitative entry with no narrative authoring looks like. Every figure the calculator computes is present. Every disclosure requiring a sentence — B2 practices and policies, B11 convictions and fines, the B1 subsidiary and certification lists — is still Draft. The remaining thirty-seven per cent is not arithmetic. It is writing, and it is the work the tool cannot do.

VSME against ESRS, the GHG Protocol, and SECR

VSME borrows the scope architecture of corporate carbon accounting without adopting its full machinery, and it borrows the disclosure logic of ESRS without adopting its extent. Understanding what it has taken from each — and what it has left behind — prevents the two most common category errors: treating a VSME report as an ESRS-equivalent, and treating it as a GHG inventory.

The comparison that matters commercially is the first row. VSME's authority does not come from a mandate; it comes from the fact that a large undertaking with a mandate is constrained, when it turns to its suppliers, to ask for no more than VSME contains. An SME's leverage is not that it must report. It is that its customer must, and that VSME is the boundary of what the customer may extract.

Undertakings that fall inside the United Kingdom's Streamlined Energy and Carbon Reporting regime face a statutory obligation of their own, computed on a different boundary; the UK SECR calculator is the appropriate tool there. VSME and SECR are not substitutes, and an undertaking subject to SECR that also wishes to answer value-chain requests will produce both.

Filling a bank or customer questionnaire from VSME output

The output of this calculator is a set of figures, not a document. Turning those figures into an answer requires knowing which of them the requester actually needs, and — more usefully — which of their questions VSME does not answer, so that you can say so rather than guess.

Common errors

Regulatory context — EFRAG, the Commission, and Omnibus

VSME was published by EFRAG in December 2024 as the Voluntary Sustainability Reporting Standard for non-listed small and medium-sized undertakings. The European Commission adopted it as a Recommendation on 30 July 2025. A Recommendation is not binding; its legal effect is to establish VSME as the standard the Commission intends parties to use when a voluntary SME disclosure is called for. That is the entirety of VSME's legal status, and it is enough.

What the calculator does and does not track

The calculator implements the December 2024 VSME standard. It does not model the CSRD value-chain cap, does not track the Omnibus amendments, and does not determine whether any particular request from any particular counterparty falls inside or outside what that counterparty may require. The Omnibus package changes the directive; it does not change the standard. An SME preparing a VSME report today prepares the same report it would have prepared before Omnibus, and the regulatory material in this article should be read as a review-dated snapshot rather than as current legal advice.

Data sources and factor versioning

Fuel and grid factors update annually. DEFRA publishes each June; Ember publishes its Yearly Electricity Data on a rolling basis; EPA publishes eGRID at intervals of eighteen to twenty-four months. IPCC AR6 hundred-year global warming potentials are stable and will not change before AR7. VSME's own versioning is independent of all of these — the December 2024 edition will apply across successive factor vintages until EFRAG revises it.

The calculator stamps each result with the MasterBrain version against which the computation was performed. A figure computed against one vintage and the same figure computed against a later vintage are distinguishable in restatement work, which matters because a VSME intensity reported to a lender in one year and a different intensity reported the next may reflect a change in the grid rather than a change in the undertaking. Disclose the factor vintage alongside the figure.

The greenhouse gas basis, as set out in §6, is mixed. Each factor carries the basis its publisher embedded, and this calculator does not restate any of them onto a common basis. Where a counterparty requires a single stated GWP basis for the whole inventory, that is a restatement exercise conducted outside this tool.

What's next

A completed Basic Module is a VSME report. Most SMEs need nothing further, and the correct next step for most is to publish it, send it to whoever asked, and repeat it next year. For undertakings whose counterparties want more, three paths lead outward.

Frequently asked questions

Methodology notes and limitations

Standard version. Calculator implements the EFRAG Voluntary Sustainability Reporting Standard for non-listed SMEs (VSME), December 2024, adopted by the European Commission as a Recommendation on 30 July 2025. The engine implements that edition's disclosure paragraphs 24–65 and guidance 66–244. Engine version 1.0.1.

Scope boundary. B3 greenhouse gas emissions are gross Scope 1 plus gross Scope 2 only. Scope 2 is location-based only, per §30(b). No Scope 3 figure is computed by any method. There is no spend-based estimation path, no market-based Scope 2 basis, no residual-mix accounting, and no treatment of energy attribute certificates or power purchase agreements.

Intensity. One metric, per §31: total Scope 1 plus Scope 2 in kgCO₂e, divided by turnover in euro, multiplied by one thousand. No per-employee, per-area, or per-output intensity is defined by the standard or emitted by the engine.

Factor reads. Four MasterBrain paths, and only four: fuels.gbr.<slug>.<unit> for stationary combustion; mobile_combustion.<slug>.<unit> for mobile combustion; grid.<iso3>.electricity.location_based for Scope 2 electricity; gwp.<gas>.ar6_100 for refrigerant global warming potentials.

Mixed GWP basis. Refrigerant leakage uses IPCC AR6-100 GWPs. Fuel and grid factors carry the basis embedded by their publishers — DEFRA 2026 is AR5-derived — and are not restated. The result-hero badge's AR6 token is accurate for the refrigerant path only. No figure on this page should be described as inventory-wide AR6.

Grid coverage. United Kingdom electricity uses DEFRA 2026. United States electricity uses EPA eGRID 2023 national average. All other countries use Ember Yearly Electricity 2025. A small number of countries have no MasterBrain grid row; for these the engine falls back to a hardcoded constant and surfaces a "no factor in MasterBrain — approximate" warning. A figure carrying that warning is a screening estimate.

No currency conversion. Turnover must be supplied in euro, or converted to euro before entry at a rate the undertaking supplies. The calculator performs no rate lookup and stamps no conversion date. Document the rate and date in the B1 basis for preparation.

Comprehensive Module coverage. Three of nine disclosures are computed: C3 target progress and implied linear annual reduction; C5 management gender ratio; C9 governance gender ratio. C4 climate risk is held in the readiness ledger and is not computed in this version — no scenario is run, no risk is classified, and no temperature-aligned assessment is produced.

Readiness and confidence are signals, not scores. Readiness measures mandatory datapoints marked Ready against mandatory datapoints triggered, with conditional datapoints excluded from the denominator until their condition holds per §13. The confidence tier records whether a computed value came from activity data (calculated) or a manual tonnage (estimated). Neither is a data quality score in the sense PCAF uses that term, and neither should be reported to a counterparty as a rating.

See the VSME Sustainability Reporting methodology for the full module coverage, the datapoint mapping, and the factor provenance behind each disclosure.

No assurance opinion. Results produced by this calculator are estimates. They do not constitute an assurance opinion, and VSME contemplates none. Review them with a competent person before use in a financing application, a tender response, a customer questionnaire with contractual consequences, or any disclosure on which a third party will rely. The regulatory material in §11 is a review-dated snapshot of a moving directive-level position and is not legal advice.