On 18 September 2026 the Securities and Exchange Commission announced that two new kinds of sustainable debt are now permitted in Thailand: transition bonds และ Thailand amber bonds. In the same package it tightened the rules for every green, social, sustainability and sustainability-linked bond. Issuers must now publish a bond framework and appoint an independent external review provider to give an opinion or assurance on it.
The rules sit in nine notifications dated 8 September 2026. They were published in the Royal Gazette and have been in force since 16 September 2026. For energy, cement, chemicals, aviation and other high-emitting companies, this is the first domestic bond label built for financing a transition rather than projects that are already green. For any company that already has an ESG bond, it changes what has to be written down, and who has to sign it off.
What the SEC changed on 16 September
The SEC’s release, No. 203/2026, does three things:
Proceeds go to projects aligned with the issuer’s own transition strategy or transition plan. The bond must reference ICMA’s Climate Transition Bond Guidelines or the Climate Bonds Initiative’s Climate Bonds Standard.
Proceeds go to activities classed as amber under the Thailand Taxonomy, with reference to an international green bond or sustainability bond standard.
For all ESG bond types, the issuer discloses a bond framework and appoints an independent external review provider to give an opinion or assurance on it.
The existing waiver of application and filing fees for ESG bonds now also covers the two new types, until 31 May 2028.
These regulatory amendments will help enhance the competitiveness of Thai businesses by enabling them to access funding sources to support their adaptation to environmental changes, which will help attract investment from both domestic and foreign investors.
SEC Thailand, News No. 203/2026, 18 September 2026The rules went through two rounds of consultation: on the principles, from 10 April to 11 May 2026 (SEC News No. 76/2026), and on the draft regulations, which closed on 21 August 2026. The SEC says most respondents agreed with its approach. The consultation paper explains the gap they fill. Thai ESG bond issuance had grown steadily, to 46 issuers and about ฿1.15 trillion in offerings from 2019 to January 2026, a figure the SEC notes includes issues it does not regulate, such as Ministry of Finance sustainability bonds. But the rules had no place for companies that cannot yet finance green projects and need money to get there. Our guide to green bond frameworks in Thailand covers the labels that already existed.
Transition bonds and amber bonds, side by side
| Transition bond | Thailand amber bond | |
|---|---|---|
| กลยุทธ์การใช้เงินที่ระดมได้ | Projects aligned with the issuer’s transition strategy or plan | Activities classed as amber under the Thailand Taxonomy |
| Standard referenced | ICMA Climate Transition Bond Guidelines, or CBI Climate Bonds Standard | An international green bond or sustainability bond standard, plus the Thailand Taxonomy |
| What has to be credible | กระบวนการรับรองนิติกรณ์เอกสาร ของบริษัท transition plan | กระบวนการรับรองนิติกรณ์เอกสาร activity’s emissions against taxonomy thresholds, plus do-no-significant-harm and minimum social safeguards |
| Changing the use of proceeds | Only to activities named in the framework, using the bondholder-rights procedure | Only to amber activities named in the framework, using the bondholder-rights procedure |
| If the rules tighten | ไม่สามารถใช้ได้ | A revised filing, updated framework and new reviewer report if taxonomy criteria change |
Labels and standards: SEC News No. 203/2026. Safeguards, change rules and taxonomy-revision rule: SEC consultation paper, April 2026. The final notifications may differ in detail from the consultation.
The difference matters. An amber bond is judged activity by activity. The consultation paper’s example is gas-fired power, where the amber emissions ceiling falls from 381 gCO2e/kWh for 2022–2025 to 225 for 2026–2030, 191 for 2031–2035 and 148 for 2036–2040. A transition bond is judged at the level of the company. Its example is an airline with a 2050 net-zero target financing engine efficiency and sustainable aviation fuel. That puts the issuer’s whole transition plan under review, not just the project. Our Thailand Taxonomy guide explains the green, amber and red tiers.
The amber label also carries a built-in risk. The paper proposes that bond factsheets warn investors that taxonomy criteria may get stricter, and that an activity could fall out of alignment during the bond’s life. If the criteria change, the issuer must file a supplement with a revised framework and a fresh reviewer report.
The quieter change: a framework and a reviewer
Before these rules, the SEC required an external reviewer only for sustainability-linked bonds sold to the public, to high-net-worth investors, or through crowdfunding with retail investors. Green, social and sustainability bonds had no such requirement. The consultation proposed extending it to all of them, and to the two new types, on the same offerings. The release confirms the framework-and-reviewer requirement now applies across ESG bonds.
The consultation paper set out what that means:
- Who may review. A provider with experience, expertise or a methodology for assessing ESG bonds or the sustainability issues of the funded projects. The paper’s examples are taxonomy assessment, science-based target setting, and verification of greenhouse-gas reductions.
- What they review. Whether the framework meets the standard, handbook or taxonomy it references.
- What the investor sees. The reviewer’s qualifications, the scope of the review, and the report itself, such as a second-party opinion.
- What the framework must contain. The four core components of the international standards: use of proceeds, project evaluation and selection, management of proceeds, and reporting.
One honest point: this formalises what the market already does. The SEC’s own paper says every Thai ESG bond issuer to date has appointed an external reviewer. The change is that the reviewer and framework are now part of the regulated filing, so investors and the SEC can hold an issuer to them. For sustainability-linked structures specifically, see our SLB guide.
After the bond is sold
Why this lands on your annual disclosure too
A transition bond does not stand on its own. Its framework points to the issuer’s transition plan, and that plan also appears elsewhere: in the 56-1 One Report, the sustainability report, investor presentations and, for SET50 companies from FY2027, in climate disclosures under the SEC’s IFRS S1 and S2 roadmap. IFRS S2 asks companies to disclose information about any climate-related transition plan they have. A reviewer checking a transition bond framework and an analyst reading the One Report will then be looking at the same targets, base years and capital plans. If the two documents disagree, both readers will notice.
The documents may also be in different languages. The One Report filed with the SEC is in Thai, and only the Thai text has legal force. The SEC says it wants these bonds to attract foreign investors as well as domestic ones, and foreign investors read the English editions. FTSE Russell scores from public disclosure only, with no questionnaire, and Thai is not among the research languages named in its FAQ (v1.5 §1.8). SET recommends English disclosure for that reason. So the transition targets in the Thai filing, the English sustainability report and the bond framework need to say the same thing in both languages, with the same figures and the same boundaries. Owning the accuracy of the English version is risk control. The SET50 climate-disclosure guide and our note on bilingual IFRS S1 and S2 disclosure set out the wider obligation.
Where the evidence runs out
- We read the release and the consultation papers, not all nine notifications. Detail on reviewer qualifications, post-issuance reporting and the taxonomy-revision rule comes from the April 2026 principles paper. A second hearing on the draft text followed, so the final wording may differ.
- Scope of the reviewer rule. The consultation applied it to public offerings, high-net-worth placements and retail crowdfunding. Whether placements only to institutional investors are covered should be checked against the final notifications.
- No language rule. Nothing in the release or the consultation says which language a framework or reviewer report must be in. The case for consistent Thai and English versions is about investor readership and accuracy, not a regulatory requirement.
- Little demand data yet. The rules are two weeks old. We found no Thai transition or amber bond issued under them so far.
- No evidence that language moves a rating. We know of no primary source showing a Thai-language disclosure scores lower. Thai companies’ FTSE Russell ESG Scores have been rising, according to SET’s own data.
What an issuer should do now
One transition story, in both languages
Othello prepares the English edition of your One Report, sustainability report and bond framework under ISO 17100 Translate-Edit-Proofread, together with the ESG advisory and TGO CFO carbon inventory behind your transition targets.
ทดลองใช้ Gap Audit ฟรีThe new labels give Thailand’s highest emitters a domestic route to transition finance. They also mean an issuer’s transition plan will be read in more places and by more readers. Start with a TGO-certified organisational footprint, keep the English edition as accurate as the Thai one (see our note on ESG translation risk and our bond framework translation service), and follow the final rules on our regulatory tracker →
Sources, read 2 October 2026: SEC Thailand, News No. 203/2026 (18 September 2026), including its list of nine notifications dated 8 September 2026; SEC Thailand, News No. 76/2026 (10 April 2026) and the Thai-language consultation paper on transition bonds, Thailand amber bonds and ESG bond disclosure; SEC hearing summary on the draft regulations (hearing 42/2569, closed 21 August 2026); FTSE Russell ESG Scores FAQ v1.5 §1.8. Quotations from Thai are our translations.
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