Electronic Signature vs Digital Signature in Thailand (2026)

"Electronic signature" and "digital signature" are not the same thing, even though most people use the terms interchangeably. Electronic signature is the broad term, covering nearly every method of confirming digital consent, under Section 9 of the Electronic Transactions Act B.E. 2544 (2001) (ETA). Digital signature, on the other hand, is just one specific technique within that broader category, one that uses encryption and electronic certificates under Sections 26 and 28.

This mix-up is one of the most common questions in Thailand's online document-signing market, because many people worry that if they don't use the more complex-sounding "digital signature," their document won't be legally valid. This article clears it up in 2 minutes, with no unexplained jargon.

TL;DR: "Electronic signature" is the broad term covering every method of confirming digital consent, and it's binding under Section 9 of the Electronic Transactions Act B.E. 2544 (2001) (ETA). "Digital signature" is one specific type of electronic signature that uses encryption technology and electronic certificates under Sections 26-28. Most SMEs get by with a standard electronic signature paired with OTP and an audit trail; that's enough for the vast majority of contracts.

Key Takeaways

• Electronic signature (Section 9) is the broad term, covering nearly every format that can identify the signer.
• Digital signature (Sections 26-28) is a specific technique that uses encryption and electronic certificates.
• Both are legally binding; the difference is in the level of evidentiary weight, not legal validity.
• Most SMEs don't need a certified digital signature; a standard electronic signature combined with OTP and an audit trail is enough.
• The government's D-Sign platform is a separate matter from both of the above, reserved for government agencies.

If you'd like to read the full overview of electronic signature law in Thailand before diving into the difference between these two types, you can find it in that article.

The Basics: What Is an Electronic Signature? What Is a Digital Signature?

What Is an Electronic Signature?

Electronic signature is the broadest definition under Thai law, covering any letter, character, number, sound, or electronic symbol used to identify the person signing. Under Section 9 of the Electronic Transactions Act B.E. 2544 (2001), this definition ranges from typing your name at the end of an email, to ticking an "I agree" checkbox, to drawing a signature with your finger on a phone screen.

The core condition for something to count as a "signature" under the law is that it must be able to identify the signer and show that they actually accepted the content of that electronic record. The law doesn't mandate any specific technology; it only sets the outcome that must be achieved.

What Is a Digital Signature?

Digital signature is a specific type of electronic signature that uses public-key encryption technology (PKI, Public Key Infrastructure) to verify the signer's identity and prevent the data from being altered after signing. This is set out in Sections 26 and 28 of the same Act.

The key difference is that a digital signature usually involves an electronic certificate issuer, a Certification Authority (CA), acting as a third party to confirm that the encryption key genuinely belongs to the signer. That makes the process more complex than a standard electronic signature, but it also delivers a higher level of technical trust.

The Difference: Comparison Table

The main difference between these two types lies in the level of technical process used to build the evidence, not legal validity. Both a standard electronic signature and a digital signature are equally binding under the law. What differs is the weight of the evidence if a dispute arises.

An important point to understand clearly: the common misconception that electronic documents carry weaker evidentiary weight isn't always accurate. A document signed with a standard electronic signature can still be used as evidence; it's just that its evidentiary weight may be lower than a signature backed by a more rigorous identity-verification process. If a dispute arises and the other party denies signing, having OTP and an audit trail attached makes it far easier to prove identity.

Which One for What: Real-World Use Cases

The choice of signature level should depend on the risk and value of the transaction, not on chasing the most complex-sounding technology. Most businesses do just fine with a standard electronic signature paired with supplementary identity verification.

Lease Agreements, Employment Contracts, NDAs

For this category of documents, a standard electronic signature paired with OTP by email or phone and an audit trail is enough in practice, because the risk exposure for the parties involved is manageable, and this level of identity verification already adds enough evidentiary weight for this type of contract.

See an example of an electronically signed condo lease agreement to see how this works in practice.

Bank Documents and High-Value Government Filings

Documents in this category usually require a higher level of trust, and in many cases use a CA-certified digital signature, because the risk value of the transaction is very high, and these institutions typically have their own internal processes that set their own technical standards.

Powers of Attorney and Executive-Level Documents

A power of attorney is often an example of a document where many parties choose a stricter-than-usual level of identity verification, even if it doesn't reach a full digital signature, because the legal consequences of this type of document are greater than those of an ordinary contract.

Legal Backing: Section 9 vs. Sections 26/28 Summarized

Both Section 9 and Sections 26-28 fall under the same law, the Electronic Transactions Act B.E. 2544 (2001), as amended in B.E. 2551 (2008), which means both levels are legally binding. The difference isn't about "legal or not"; it's about the weight of the evidence if a dispute arises.

OTP and an audit trail that records the time, device, and IP address of the signer significantly strengthen the evidentiary weight of the record, but that strengthens evidentiary weight, not a guarantee of the outcome of a case in court. Every case has its own context; the court weighs all the evidence together.

For the full legal picture supporting electronic signatures in Thailand, including the exceptions and the new draft legislation for 2026, read more at the full law behind electronic signatures in Thailand and evidentiary weight in court

Frequently Asked Questions

Does a digital signature always need a certificate from a CA?

Yes. Under the definition in Section 28, a digital signature certified by a Certification Authority (CA) requires a third party to confirm the validity of the encryption key. Without a CA certificate, it falls instead into the category of a standard electronic signature or a reliable electronic signature.

Is D-Sign the same as a digital signature?

Not entirely. D-Sign is a digital signature system developed by the Digital Government Development Agency (DGA), designed for use within government agencies and official government dealings only; it isn't a service private businesses can sign up for directly. Private businesses should use a private-sector electronic document-signing platform instead.

Do SMEs need to use a digital signature?

In practice, most SMEs don't. A standard electronic signature with OTP identity verification and an audit trail logging activity is enough for lease agreements, employment contracts, and most business documents. A CA-certified digital signature is usually reserved for very high-value transactions or specialized government documents.

Does OTP turn an electronic signature into a digital signature?

No. OTP is an identity-verification mechanism that strengthens the trustworthiness of a standard electronic signature, but it doesn't turn it into a digital signature under Sections 26-28, which requires PKI encryption technology and usually a CA certificate as well. The two are separate mechanisms that can work alongside each other.

Which documents should lean toward a digital signature?

Documents carrying very high risk value, or transactions with institutions that set their own specific technical standards, such as certain banking transactions or certain government documents, usually use a CA-certified digital signature. For an SME's ordinary business contracts, a reliable electronic signature is enough.

Can a standard electronic signature be used in court?

Yes. A document signed with a standard electronic signature can be used as evidence in court; it's just that its evidentiary weight may differ from a signature backed by more rigorous identity verification. Adding OTP and an audit trail strengthens the evidentiary weight, but it isn't a guarantee of the case's outcome.

Conclusion

Electronic signature and digital signature are two related concepts, but they are not the same term. Electronic signature is the broad term covering every method of confirming digital consent under Section 9. Digital signature is a specific technique using encryption under Sections 26-28. Both are legally binding; the difference lies in the level of evidentiary weight, not legal validity.

For SMEs, real estate agents, or clinics, a standard electronic signature with OTP and an audit trail is enough for most contracts.

Start your free trial to see whether Jabmue's bilingual Thai legal document templates with OTP and an audit trail fit your business workflow.

Further Reading

• The full law behind electronic signatures in Thailand
• Evidentiary weight in court
• An example of an electronically signed lease agreement
• Powers of attorney that usually need a higher level of trust
• Data protection when signing documents online

This content is general information for educational purposes, not legal advice for a specific case. Before making an important business decision, consult your legal advisor to assess your business's specific situation. Article prepared by the Jabmue team.