The new ESG reporting standard: What’s changing and what does it mean for Mexican issuers?

Starting in 2025, sustainability reporting in Mexico will enter a new phase. The CNBV amended the Circular Única de Emisoras to make the IFRS Sustainability Disclosure Standards—IFRS S1 and S2, issued by the International Sustainability Standards Board (ISSB)—mandatory for listed companies. This change aligns Mexican reporting requirements with leading international ESG standards. 

What’s changing and why is it relevant? 

Until now, the Global Reporting Initiative (GRI) has been the most widely used framework in Mexico, with a different focus than the one proposed by ISSB:  

• GRI: focused on the company’s external impact across its various stakeholders, analyzing economic, environmental, social, and governance-related issues. 

• ISSB: centered on double materiality, integrating both sustainability factors and financial material information. 

As a result, the ISSB requires companies to identify and quantify how ESG-related risks and opportunities affect their profitability and overall business resilience. 

What are S1 and S2 about? 

These are general guidelines for disclosing sustainability-related risks and opportunities: 

• S1: requires companies to connect sustainability with its impact on cash flows, cost of capital, and business strategy. 

• S2: focuses on climate-related disclosures and may be more complex to implement, as it requires climate scenarios and other types of data that many companies are not yet measuring. 

Who will find it easier to adapt? 

• Companies that already have reporting processes in place, especially those familiar with working through different climate scenarios. 

• S2, in particular, will be easier to adopt for companies already aligned with the Task Force on Climate-related Financial Disclosures (TCFD) recommendations. 

Who will face more challenges? 

• Companies that haven’t started identifying their sustainability-related risks and opportunities. 

• Companies without systems to manage and report quantitative ESG information. 

What does the CNBV require? 

1. Standalone annual sustainability report: mandatory starting with FY2025 (to be published in 2026), aligned with IFRS S1 and S2. 
2. Independent assurance of the report: 

• • FY2025 (published in 2026): not required 

• • FY2026 (published in 2027): limited assurance 

• • FY2027 (published in 2028): reasonable assurance (higher level) 

   3. Identification of Key Sustainability Indicators to be measured across environmental, social, and governance topics.

     4. Exceptions: 

• • Regulated financial institutions will follow a gradual implementation process (details still to be defined). 

• • Foreign issuers listed in Mexico may report using their home-country standards if they demonstrate equivalency with IFRS S1 and S2. 

How to start preparing? 

1. Strategy diagnosis: Evaluate whether the current materiality analysis aligns with the concept of double materiality. If it does not, revise it accordingly. If no materiality analysis has been conducted yet, this should be the first step. 

1. Reporting diagnosis: Review current reporting practices against ISSB standards to identify gaps and areas needing improvement. 

1. Quantify impacts: Work with multidisciplinary teams to begin measuring the impacts of material sustainability issues. 

1. Strengthen corporate governance: ensure ESG strategy is supervised by the Board and executive leadership. Create or update relevant committees if needed. 

1. Training (including the IR team): Equip teams with the knowledge and tools to address questions regarding disclosures under the new standards. 

1. Monitor regulatory updates: Stay up to date with any additional guidance from the CNBV to ensure timely adjustments to your implementation plan. 

This change goes beyond compliance. Use the process to identify business opportunities, develop more resilient internal processes, and attract long-term, responsible investors. If you need support to get started, at Miranda Partners, through our Miranda ESG division, we’ll be happy to help. 

Is your company ready? 

If you’d like to learn more, here are some related blogs you may find useful: 

https://miranda-partners.com/es/issb-vs-gri-our-take-on-how-to-prepare-for-a-new-phase-in-sustainability-reporting/ 

https://miranda-partners.com/es/gri-vs-issb-s2/ 

https://miranda-partners.com/gri-vs-issb-topics-and-governance/#:~:text=For%20example%2C%20ISSB%20focuses%20on,and%20other%20commitments%20of%20members. 

https://miranda-partners.com/gri-vs-issb-risk-management-and-stakeholder-engagement/ 

https://miranda-partners.com/gri-vs-issb-strategy/