Short answer: companies listed on the Stock Exchange of Thailand (SET) and mai must file the Form 56-1 One Report within three months of their fiscal year-end. For most Thai listed companies, whose financial year ends on 31 December, the 2026 filing deadline therefore falls at the end of March 2026 for FY2025. The filing itself is made in Thai; an English edition is not a general SEC filing requirement, but it is the version international investors and ESG raters actually read. Always confirm the exact date for your fiscal year with the SEC and SET.
- What is the Form 56-1 One Report?
- When is the 56-1 One Report deadline in 2026?
- Is an English version mandatory?
- What’s inside the One Report that needs translating
- What’s new for 2026: IFRS S1/S2 and FTSE Russell
- How to hit the deadline with a clean bilingual report
- Frequently asked questions
- Related ESG guides
What is the Form 56-1 One Report?
The 56-1 One Report consolidated the old annual registration statement (Form 56-1) and annual report (Form 56-2) into a single disclosure document. It took effect for fiscal years beginning in 2021, so listed companies have filed in the One Report format since 2022. It brings a company’s financial statements, management discussion and analysis (MD&A), corporate governance, risk factors and sustainability information together in one filing for regulators and investors.
Short answer: companies listed on the Stock Exchange of Thailand (SET) and mai must file the Form 56-1 One Report within three months of their fiscal year-end.
56-1 One Report Deadline 2026 | Thailand Filing GuideWhen is the 56-1 One Report deadline in 2026?
The filing window is three months from the end of the fiscal year. Because the large majority of SET-listed companies use a 31 December year-end, their FY2025 One Report is due by approximately 31 March 2026. If your company uses a different fiscal year-end, your deadline shifts accordingly — three months after your own year-end. These are statutory timelines, so confirm the precise date with the SEC and SET for your filing.
Thailand’s integrated annual + sustainability filing to the SEC.
Where FTSE/ISSB-relevant disclosure lives — read in English by raters.
A compliant Thai One Report satisfies the SEC; the English edition earns the score.
Is an English version mandatory?
No — not as a general filing rule. The 56-1 One Report is filed with the SEC in Thai, and there is no blanket SEC or SET regulation requiring every listed company to publish an English edition. The language obligations that do exist are narrow and specific: under SET regulation Bor.Jor./Por. 11-00, a listed company with foreign shareholders must send them the notice calling a general meeting, with supporting documents, translated into English; and SET’s periodic disclosure rulebook flags the report on use of funds from a capital increase as a Thai-and-English item.
The real reason the English edition matters is commercial, not statutory. From 2026 the SET assesses listed companies under FTSE Russell ESG Scores, and FTSE Russell scores publicly disclosed information with no questionnaire to fall back on. Its ESG Scores and Indices FAQ (v1.5, December 2025, section 1.8) names the key languages its research covers as English, French, Spanish, German, Japanese and Chinese — Thai is not among them. Disclosure that exists only in Thai is therefore not the disclosure your score is built from. There is also one place where bilingual publication is an explicit condition: companies applying voluntarily for the 2026 FTSE Russell assessment must download their SET ESG Data Platform submission as a PDF and publish it on the company website in both Thai and English by 6 May 2026.
In practice this means the entire One Report — not just the headline numbers — benefits from an accurate, consistent English version delivered on the same timeline as the Thai filing. See our annual report & 56-1 One Report translation service for how this is handled end-to-end.
What’s inside the One Report that needs translating
- Audited financial statements and the notes to the accounts
- The independent auditor’s report
- Management discussion & analysis (MD&A)
- Corporate governance and board structure
- Risk factors and internal control
- The sustainability / ESG section
What’s new for 2026: IFRS S1/S2 and FTSE Russell
Two shifts make high-quality English disclosure more important than ever. First, Thailand is phasing in IFRS S1 and S2 sustainability disclosures, beginning with SET50 companies from 2027 and SET100 from 2028. Second, from 2026 the SET is transitioning from its own SET ESG Ratings to FTSE Russell ESG Scores — and FTSE Russell assesses companies using publicly disclosed information only, in the languages its research covers — English, French, Spanish, German, Japanese and Chinese (FAQ v1.5, s1.8). Thai is not on that list. A weak or late English translation of your sustainability section can directly cost you points.
How to hit the deadline with a clean bilingual report
Start the translation workstream in parallel with drafting, not after sign-off. Lock a financial terminology glossary up front so figures, account names and governance terms stay consistent. Use an ISO 17100 process (translation plus independent review) for accuracy on numbers and disclosures, and put confidentiality (an NDA, secure handling) in place from the first email, since the report is price-sensitive before release. Talk to Othello International for a quote on your One Report.
Frequently asked questions
When exactly is the 56-1 One Report due?
Within three months of your fiscal year-end. For a 31 December year-end that is around 31 March the following year.
Do I need an English version of the 56-1 One Report?
Not as a general SEC filing requirement — the One Report is filed in Thai. Most SET- and mai-listed companies publish an English edition anyway, because that is the version international investors read and the version FTSE Russell can score: Thai is not among the six languages FTSE Russell states its research covers.
Does the sustainability section need translating too?
Yes. With IFRS S1/S2 phasing in and FTSE Russell scoring from public English disclosure, the ESG section is increasingly important to translate accurately.
Related ESG guides
- Carbon Credits in Thailand 2026: T-VER, Premium T-VER and What Corporates Need to Know
- What Is ESG? A Practical Guide for Thai Companies (2026)
- CSRD After the Omnibus: What Thai Suppliers to EU Companies Actually Need to Provide (2026)
- CBAM in 2026: What Thai Exporters Must Do as the Definitive Phase Begins
- The 56-1 One Report ESG Section: What SET-Listed Companies Must Include (2026)
Related Othello services
📘 Free resource: Explore The FTSE 2026 Playbook Library — Othello’s ESG disclosure playbook plus focused editions for Thai banks, energy, property, healthcare, technology and more.
Related services from Othello International
Othello International is a Bangkok-based bilingual (EN↔TH) technical translation and ESG advisory firm. Related specialist services:
- 56-1 One Report translation — the SET integrated disclosure
- ESG disclosure translation — IFRS S2, GRI, FTSE-ready
- capital markets translation — 56-1, prospectus, filings
See what your English disclosure is scoring
From 2026 FTSE Russell scores SET-listed companies from public English disclosure — no questionnaire. Run the free Gap Audit and find the points you are leaving on the table.
Run the free Gap AuditSee where your English edition is losing FTSE points.
A free Gap Audit maps your published English disclosure against FTSE Russell’s 14 themes — and shows exactly which gaps are quietly costing you points, index inclusion and investor attention.
