Notary Public Document Certification

Thailand does not operate a separate notary profession as some countries do. It uses Notarial Services Attorneys — lawyers who have completed the training and are registered with the Lawyers Council of Thailand. Typical acts are certifying a signature executed in the attorney’s presence, certifying that a copy matches the original examined, administering an oath or affirmation, and certifying facts personally witnessed, all within the scope the law and the Council’s regulations allow.

The receiving authority decides, not the sender. Read the instruction letter, application form or website of the university, embassy, bank, registrar or counterparty and note the exact wording: notarised, certified true copy, sworn statement or legalised. Then work backwards to sequence the steps, because each of those terms refers to a different act. Starting from the actual written requirement avoids duplicated work and rejected documents.

Certifying a copy confirms that the attached copy matches the original the attorney examined, so the original must be produced. Certifying a signature confirms that the named person signed in the attorney’s presence after producing identification, so the signatory must attend and must not have signed in advance. Neither act certifies that the content of the document is true or legally valid — that distinction matters when an authority asks for one and not the other.

Bring the original document to be certified, valid photo identification such as an ID card or passport, and — if signing for a company — the current company affidavit plus evidence of signing authority. Bring the receiving authority’s instruction letter if you have one, because some bodies prescribe specific wording for the certificate. If a translation is needed, say which target language in advance so the steps can be sequenced correctly.

Thailand acceded to the Apostille Convention on 30 June 2026, and the Convention enters into force for Thailand on 28 February 2027. Until that date, Thai documents for overseas use still follow the existing route: legalisation by the Department of Consular Affairs of the Ministry of Foreign Affairs, followed by the destination country’s embassy or consulate where required. Once it is in force, confirm with the receiving authority whether it accepts an Apostille or still asks for the previous chain.

The order depends on the receiving authority. Some require the Thai original to be certified first and the translation certified afterwards; some require the translation attached to the original and certified together as one bundle; some accept translations only from specified translators. Getting the order wrong usually means repeating the whole chain, so confirm both the sequence and the required binding format with the receiving authority before the first step.

The signatory must be a director with signing authority as shown on the current company affidavit, or an attorney-in-fact holding a power of attorney with a clearly defined scope, with identification for both grantor and grantee. If the affidavit requires joint signatures and a company seal, all of those conditions must be met. Otherwise the receiving authority may reject the document even though the signature certification itself was performed correctly.

It depends on the act. Preliminary document review and drafting the certificate wording can be done from copies sent in advance. Signature certification, by its nature, requires signing in the attorney’s presence with identification produced, and copy certification requires the original to be examined. Plan which steps can be handled remotely and which need attendance, then arrange a single appointment that covers all the in-person steps at once.

Common causes: the wrong type of certification for what the authority specified, certificate wording that does not match a prescribed form, names or document numbers that differ from the passport or civil registry, a missing onward legalisation step, a translation that omits pages or seals, a document older than the recipient’s validity window, or a bundle separated after certification. Checking the written requirement before starting removes most of these failures.

The certificate itself carries no built-in expiry, but many receiving authorities accept only documents issued within a set window, commonly three or six months. Certain source documents — a company affidavit or a civil registry extract, for example — carry their own freshness requirement. Check the recipient’s rule first, then schedule the certification dates so the bundle is still within the window on the day you actually file.