Electronic signatures in Thailand 2025 for foreign SMEs: what you can e-sign, what you cannot, and how to handle e-Stamp Duty

Electronic signatures in Thailand 2025 for foreign SMEs: what you can e-sign, what you cannot, and how to handle e-Stamp Duty

Introduction

Moving contracts online can speed up deal cycles and audit trails, but only if your workflows follow Thai law. This guide explains electronic signatures in Thailand 2025 for foreign SMEs: when e-signatures have legal effect, reliability requirements, key exclusions, documents that still require land office registration, and how to pay e-Stamp Duty correctly for electronic instruments. All rules are tied to the Electronic Transactions Act, the Royal Decree on exclusions, the Civil and Commercial Code, and Revenue Department guidance.

The legal foundation you must know

• E-documents cannot be denied legal effect just because they are electronic. Section 7 of the Electronic Transactions Act B.E. 2544 (ETA) says information shall not be denied legal effect solely because it is in the form of a data message.

• Writing and signature requirements can be satisfied electronically if reliability conditions are met. Sections 8 to 10 and 9 set the rules for “in writing,” “original,” and “signature” via data messages, including the need for a method that identifies the signatory and is reliable and appropriate for the purpose.

• Reliable electronic signature standard. Section 26 lists criteria for a “reliable electronic signature,” including exclusive control of signature-creation data and detectability of changes after signing. Use solutions that meet these properties and maintain evidence logs.

• Admissibility in court. Section 11 confirms data messages are admissible as evidence; courts assess weight based on reliability of generation, storage, transmission, and identity proofing.

What you cannot e-sign under Thai law

The Royal Decree Prescribing Civil and Commercial Electronic Transactions Excluded from the Application of the Law on Electronic Transactions B.E. 2549 (2006) removes two categories from ETA coverage: family and succession transactions. Do not use e-signatures for wills, marriage, divorce, or similar family law instruments.

Practical implication: an electronic will or other succession instrument is not valid under current Thai law.

Electronic signatures in Thailand 2025 for foreign SMEs: contracts that still need registration

Some transactions are valid only if made in writing and registered with the competent official, which means an e-signature alone will not complete the legal effect because you must still register at the relevant authority. Example: sale of immovable property must be in writing and registered to be valid.

Workflows: it is acceptable to e-sign a draft for commercial alignment, but title to land transfers only on registration at the Land Office. Keep a wet-ink or authority-approved instrument ready for registration day.

Building a reliable e-signature stack

• Identity and intent. Your signing method must identify the signatory and show approval of the document. Multi-factor authentication plus a clear “I agree” action meets ETA Section 9 principles when implemented well.

• Integrity and originals. Preserve tamper-evident hashes and an immutable audit trail so the electronic record qualifies as an “original” under Section 10.

• Policy and evidence. Maintain logs showing signature creation data control, certificate details if used, IP, time stamps, and post-signature document integrity for Section 26 reliability.

When e-signing triggers e-Stamp Duty

Thailand levies stamp duty on certain instruments. For electronic instruments, the Revenue Department’s e-Stamp Duty system allows payment online using Form Or.Sor.9, either before execution or within 15 days from the date of execution, with specific late-payment rules handled at area revenue offices.

Common electronic instruments subject to e-Stamp Duty include: hire of work, loan/overdraft agreements, power of attorney, proxy for company meetings, and guarantees. The list was expanded by Director-General Notifications to cover additional e-instruments.

Compliance pattern: upload Or.Sor.9, pay via the Revenue Department channel, and keep the receipt or payment code with your contract file. Where late, expect surcharges under Revenue Department practice.

Quick decision tree

1. Is the transaction about family or succession such as wills or marriage documents? If yes, do not e-sign.

2. Does the transaction require registration to be legally effective, for example sale of immovable property? E-sign for commercial intent if desired, but plan for formal registration to complete validity.

3. Is the instrument stamp-dutiable as an e-instrument such as loan, guarantee, or hire of work? If yes, submit Or.Sor.9 and pay within 15 days online.

4. For all other business contracts, implement a reliable e-signature flow that meets ETA Sections 9, 10, 11, and 26.

Compliance checklist for legal and finance teams

• Map your contract types and mark which are excluded by the Royal Decree or require registration.

• Standardize your e-signature platform settings to meet ETA reliability factors and maintain court-ready evidence.

• Build an e-Stamp Duty calendar and operating procedure for Or.Sor.9 submissions and receipts within 15 days for e-instruments.

• Train approvers to recognize when a contract needs separate government registration in addition to e-signature.

How GENTLE LAW IBL helps

We design enforceable e-signature workflows for Thai and cross-border deals, prepare clause sets aligned with ETA reliability standards, implement e-Stamp Duty controls for electronic instruments, and coordinate Land Office or other authority registrations where required.

Conclusion and call to action

Adopting electronic signatures in Thailand 2025 for foreign SMEs is safe and efficient when you confirm the legal basis, handle exclusions, and integrate e-Stamp Duty. For a one-stop rollout that covers policy, templates, audit trails, and tax stamping, contact GENTLE LAW IBL.

📩 Book a consultation: https://gentlelawibl.com