ESG reporting for Thai listed companies is entering a major transition. What used to be seen as a sustainability disclosure exercise is now becoming a board-level agenda that reflects how well a company manages risk, governance, data quality, and long-term value creation.
With the adoption of ISSB Standards, including IFRS S1 and IFRS S2, ESG Reports will need to go beyond describing sustainability activities. Companies will be expected to explain how sustainability-related risks and opportunities affect their business, how these issues are governed, how risks are managed, and which metrics and targets are used to track performance.
This shift also connects directly with the increasing importance of FTSE Russell ESG Scores, investor expectations, climate-related disclosures, and the quality of information disclosed through the 56-1 One Report, Sustainability Report, and ESG Website.
Under IFRS S1, companies are required to disclose material sustainability-related financial information, including ESG risks and opportunities that may affect cash flows, access to capital, and enterprise value.
IFRS S2 focuses specifically on climate-related disclosures. This includes climate risks and opportunities, physical risks, transition risks, and greenhouse gas emissions across Scope 1, Scope 2, and Scope 3.
In Thailand, the first phase of implementation will follow a “climate-first” approach. This means companies should begin by strengthening climate-related data, greenhouse gas emissions data, governance structures, risk management processes, and disclosure controls.
In practice, a strong ESG Report will no longer be judged only by how well it is written. It will be judged by how credible, traceable, and decision-useful the information is.
The implementation of the FTSE Russell indicators
Sustainable and Responsible Investing Funds, or SRI Funds, will be required to disclose information under the new SRI Fund criteria. These requirements aim to enhance transparency, reduce greenwashing risks, and help investors compare sustainability performance more clearly.
The requirements will begin to apply to companies in the SET50.
The requirements will be expanded to companies in the SET100.
The requirements will apply to all listed companies on the Stock Exchange of Thailand, including companies preparing for IPOs.
The requirements will apply to companies listed on the Market for Alternative Investment, or mai, as well as REITs, Infrastructure Trusts, Property Funds, and Infrastructure Funds.
This timeline gives companies time to prepare, but it should not create a false sense of comfort. ESG data, especially climate-related data and greenhouse gas emissions data, cannot be built properly at the end of the reporting year. Companies need systems, data owners, internal controls, and evidence trails in place early.
Companies should begin preparing information on climate-related risks and opportunities, including Scope 1 and Scope 2 greenhouse gas emissions.
Scope 1 covers direct emissions from company-controlled sources. Scope 2 covers indirect emissions from purchased energy. These data points require reliable calculation methods, clear data sources, supporting evidence, and, in many cases, readiness for external verification.
Although early implementation in Thailand will focus mainly on Scope 1 and Scope 2 emissions, companies should also start preparing for Scope 3 disclosure.
Scope 3 covers greenhouse gas emissions across the value chain, including upstream and downstream activities. This may involve suppliers, contractors, logistics providers, distributors, and product use by customers.
The challenge is that much of this information does not sit within the company. Companies should therefore begin engaging key suppliers, mapping value chain data, and building practical data collection processes as early as possible.
Under the new ESG reporting requirements, companies must clearly disclose how sustainability and climate-related issues are governed.
This includes the roles of the board, executives, committees, and working teams. Companies must also show how ESG risks are assessed, managed, and connected to business strategy.
IFRS S1 and IFRS S2 follow four core disclosure pillars:
This means ESG reporting is no longer the sole responsibility of the Sustainability team. It requires collaboration across risk management, finance, accounting, operations, procurement, human resources, legal, marketing, and the board of directors.
To prepare for ESG Report 2026 and upcoming ISSB-based disclosure requirements, companies should begin with the following actions:
The new ESG reporting requirements may appear to be another compliance burden. However, they also create an important opportunity for companies to strengthen risk management, improve data quality, build investor confidence, and prepare for future expectations from regulators, capital markets, and global sustainability standards.
A strong ESG Report is no longer just a communication document. It is evidence of business readiness.
For Thai listed companies, ESG reporting in 2026 and beyond will be about more than disclosure. It will be about whether the organisation has the governance, systems, data, and accountability needed to manage sustainability risks and opportunities in a credible and future-ready way.
