The Normas de Información de Sostenibilidad are the sustainability reporting standards issued by CINIF, the same council that issues Mexico's financial reporting standards, the NIF. The first two, NIS A-1 with the conceptual framework and NIS B-1 with the basic indicators, were published on May 13, 2024 and came into force on January 1, 2025.

Who do the NIS apply to?

Entities that prepare their financial statements under the Mexican NIF, whatever their size and whether or not they are listed. The indicators are disclosed in the notes to the financial statements, with comparative figures for the previous period.

What does the CNBV require from issuers?

Since the reform published in the Diario Oficial de la Federación on January 28, 2025, issuers registered in the Registro Nacional de Valores must file a sustainability report aligned with the ISSB's IFRS S1 and IFRS S2. The first covers fiscal year 2025 and is filed in 2026.

Does the sustainability report need assurance?

Yes, on a schedule. The 2026 report, with 2025 data, may be filed without assurance. The 2027 report, with 2026 data, needs at least limited assurance. From then on, reasonable assurance by an external auditor.

Do I have to report scope 3 from the first year?

No. Both NIS B-1 and IFRS S2 give a year of grace: in the first fiscal year you may omit scope 3 emissions, and no comparative information for the previous period is required.

Do financial institutions report too?

Not under this rule yet. Article 82 Bis sends financial entities that are issuers to the sustainability rules their own regulators issue, which the CNBV described as a gradual incorporation.

NIS and CNBV: sustainability reporting in Mexico

Mexican issuers filed their first sustainability report in 2026, with 2025 data. They could do it without an auditor, because the transitional provisions allow it for that report only. The 2027 report does not: it needs at least limited assurance, and the ones after it, reasonable assurance.

That means the greenhouse gas inventory for fiscal year 2026, the one being built right now, is the first an auditor will review. This guide explains the two standards behind it, CINIF's NIS and the CNBV rule, and where they overlap and where they do not.

Two standards, two audiences

It helps to separate them from the start, because they get mixed up.

	CINIF's NIS	CNBV article 82 Bis
Who issues it	CINIF, the council that issues the NIF	The CNBV, by amending the issuer regulations
Who it applies to	Entities preparing financial statements under NIF	Issuers registered in the Registro Nacional de Valores
What it asks for	30 basic sustainability indicators in the notes	A sustainability report aligned with IFRS S1 and S2
From when	Fiscal years starting January 1, 2025	2026 report with fiscal year 2025 data
Assurance	Not required by the standard	None in 2026, limited in 2027, reasonable after that

A mid-sized company that is not listed falls in the first column. An issuer falls in both: it discloses the NIS B-1 indicators in its notes and also files the full report the CNBV asks for.

The NIS: what they contain

CINIF published the first two standards on May 13, 2024. They came into force on January 1, 2025, so the first period reported under them is fiscal year 2025, in the financial statements filed in 2026.

NIS A-1 is the conceptual framework. It defines what sustainability information is, what its qualitative characteristics are and how it relates to the NIF. It is always applied together with a specific standard.

NIS B-1 is that specific standard. It sets 30 Basic Sustainability Indicators, the IBSO: 21 quantitative and 9 qualitative, all of which are disclosed. The quantitative ones are presented in absolute and relative terms, and all of them with comparative figures for the previous period.

The environmental indicators cover energy and water consumption, waste and greenhouse gas emissions by scope. Scope 3 is the only one with an explicit relief: the standard allows omitting it in the year following January 1, 2025. Comparatives are not required in the first year of application either.

CINIF says the NIS were developed in line with the first international sustainability standards, but they are not a copy of the IFRS S standards. They are anchored in the Mexican NIF and ask for a fixed set of indicators, while the ISSB standards ask for whatever is material to the investor. For an entity that only prepares NIF, the practical difference is that the list of what to measure is already written.

For small and mid-sized companies, CINIF released a free greenhouse gas calculator in July 2025, developed with support from GIZ. It walks the user through energy and fuel consumption and produces a report aligned with the Basic Sustainability Indicators.

The CNBV rule

The reform was published in the Diario Oficial de la Federación on January 28, 2025 and came into force the next day. It added article 82 Bis to the general provisions applicable to securities issuers.

The article requires issuers to prepare a sustainability report in accordance with the ISSB's sustainability disclosure standards: IFRS S1, on general requirements, and IFRS S2, on climate-related disclosures, plus whatever the ISSB issues later.

Three scope rules:

Financial entities that are issuers, and issuers whose subsidiaries are mainly financial, follow the sustainability rules the financial authorities issue for each type of entity. The CNBV described this as a gradual incorporation.
States and municipalities are excluded.
Foreign issuers may use their home country's standards. If they do, they must state that the report does not follow the IFRS S standards, or explain its interoperability or equivalence.

The report is part of the annual information already listed in articles 33 and 37 of the same provisions.

The assurance timeline

The reform's transitional provisions set three steps:

Report	Data from	Assurance
2026	Fiscal year 2025	May be filed without external auditor assurance
2027	Fiscal year 2026	At least limited
2028 onwards	Fiscal year 2027 and later	Reasonable

Reasonable assurance is the same level as a financial statement audit. For the emissions inventory, that means the auditor will ask for the activity data, the emission factor and the document behind each figure, and will recalculate a sample.

What IFRS S2 asks about emissions

IFRS S2 requires disclosing gross scope 1, 2 and 3 emissions, measured with the GHG Protocol unless an authority requires another method. Scope 3 is broken down by the standard's fifteen categories. Scope 2 is reported with the location-based method, and any contractual instrument, such as renewable energy certificates, is explained.

In December 2025 the ISSB published amendments to IFRS S2 that simplify these disclosures: they allow limiting scope 3 category 15 to financed emissions, widen the use of methods and warming potentials required by a local authority and relax the industry classification. They apply to periods beginning on January 1, 2027, with early adoption permitted.

The standard itself grants reliefs for the first period it is applied: no comparatives and no scope 3 emissions. For a Mexican issuer, that first period is the 2026 report, so scope 3 comes in with the 2027 one.

If your inventory already follows the GHG Protocol, the work is presentation. If you built it under ISO 14064-1, the GHG Protocol and ISO 14064 guide shows how categories map to scopes.

The other pieces on the board

The sustainability report is not the only emissions obligation in Mexico. Plants above 25,000 tonnes of CO2 equivalent report every year to the RENE through the COA, and several states levy carbon taxes with far lower thresholds. The RENE and COA guide explains who is required and when.

The useful part is that all three use the same data: tonnes of CO2 equivalent by source, with the fuel and electricity behind them. A well-documented inventory serves all three reports.

What we would do in your place

If you are an issuer, treat fiscal year 2026 as the first audited one, because it is. Close the organizational boundary, choose the base year and keep the invoice behind every activity figure. Limited assurance is earned with a tidy inventory; reasonable assurance, with a traceable one.

If you prepare NIF and are not listed, NIS B-1 already applies to you. The 30 indicators are disclosed in the notes with comparatives, so fiscal year 2026 needs the 2025 figure next to it. If you did not measure 2025, measure 2026 properly and document why the comparative is missing.

If you are a financial entity, your report follows the rules of your own regulator, which the CNBV announced as gradual. Check your circular before assuming the issuers' timeline, and start with the scope 3 of your lending, which is where IFRS S2 puts the focus for the sector.

Grumbic calculates emissions from your fuel and electricity invoices, classifies them by scope under the GHG Protocol and ISO 14064-1 and keeps every figure linked to the document it came from. That backing is what an auditor reviews in a reasonable assurance engagement.

See the platform or talk to us.

Sources

Information reviewed on October 17, 2026 in the Diario Oficial de la Federación and in documents from CINIF, the CNBV and the firms that analysed the reform. This guide is informative and does not replace legal or accounting advice.