Affidavits and Sworn Statements in Thailand for Use Abroad

When an affidavit is used

Foreign courts, immigration departments, registries and insurers ask for sworn statements to establish facts: identity and name differences, single status where a specific declaration is accepted, residence, lost documents, support for family members or evidence in proceedings abroad.

What the attorney confirms

The attorney confirms your identity, that you understood you were making the statement under oath or affirmation, and that you signed it in their presence. The attorney does not investigate or vouch for the facts. Making a false statement can carry serious legal consequences in Thailand and abroad.

Preparing a statement that will be accepted

Most refusals come from format, not content:

• Use the receiving authority's template or required headings.
• Write in the first person, with full names and passport numbers matching your passport.
• Number exhibits and refer to them in the statement; bring originals for any copies to be certified.
• Check whether the authority wants an oath (religious) or an affirmation.
• Confirm the language; a certified translation may be needed.

Where an embassy document is required instead

Some statements, such as an affirmation of freedom to marry for a marriage registration in Thailand, are issued by the foreign national's embassy and cannot be replaced by a notarial affidavit. We tell you before the appointment if your purpose needs an embassy or Thai government document.

Thailand acceded to the Apostille Convention on 30 June 2026 and the Convention enters into force for Thailand on 28 February 2027. Until then, documents normally follow the consular legalisation chain; from that date, an apostille may replace it for covered public documents where the Convention applies between Thailand and the destination country.

How are discrepancies in names, dates, or civil status addressed through a sworn statement?

Foreign courts, immigration authorities, and financial institutions frequently require sworn statements to clarify contradictory administrative records. Thai civil documents, including house registrations (Tabien Baan), birth records, marriage certificates, and name change certificates (Form Chor 3), often display English transliterations that diverge from spellings on foreign passports, national identity cards, driving licences, or overseas bank accounts. In probate matters, visa applications, property transactions, or pension entitlement claims abroad, even minor variations in letter sequencing, omitted middle names, or distinct maternal surnames can trigger formal evidentiary objections. An affidavit of identity or one and the same person allows the deponent to declare formally under penalty of perjury that disparate identity records refer to a single individual. The statement establishes a coherent chronological timeline accounting for historical name modifications, marital status alterations, or inconsistent administrative transliterations across jurisdictions.

Under Regulation B.E. 2551 of the Lawyers Council of Thailand, a registered Notarial Services Attorney must verify your identity in person using original, unexpired passports or official identification cards. While the attorney validates your identity, administers the oath, and attests that you executed the document in their physical presence, the attorney does not independently verify the substantive truth of your personal history. The draft must precisely itemise each name variant, cite official registration numbers, and identify the issuing municipal or district offices (Amphoe or Khet). Receiving authorities in foreign jurisdictions maintain sole discretion regarding whether an affidavit alone cures an evidentiary conflict or if supplemental certified records, official translations, or civil status extracts issued by the Thai Department of Provincial Administration must accompany the filing.

What procedural safeguards govern the swearing of an oath versus an affirmation across multiple languages?

Destination jurisdictions maintain strict procedural rules governing how a deponent pledges truthfulness in written testimony. A traditional affidavit requires swearing a religious oath invoking a deity or holy text, whereas an affirmation provides a legally equivalent secular declaration for individuals who hold non-theistic beliefs or whose personal convictions preclude religious oaths. Deponents must ascertain the precise formula required by the overseas court, government ministry, or commercial entity before attending an appointment at Thai Legal & Immigration Consulting Service Co., Ltd. Because Thailand has no civil-law notaries, notarial functions are performed by certified Notarial Services Attorneys under Lawyers Council Regulation B.E. 2551. The attorney administers the formal jurat or affirmation clause, ensuring the deponent understands that making a false statement carries severe legal penalties under Thai law as well as in the foreign jurisdiction.

Language comprehension is an essential legal prerequisite during notarial execution. When an overseas authority requires an English-language statement, a deponent who lacks fluency in written or spoken English cannot lawfully execute it without an established translation safeguard. In such scenarios, the declaration should be drafted in a dual-column bilingual format or interpreted line-by-line by a qualified translator prior to signing. The Notarial Services Attorney then incorporates an interpreter's declaration directly into the notarial certificate, identifying the interpreter, confirming their competence, and certifying that the entire text was translated orally in the presence of the attorney before the deponent affixed their signature. This procedural record helps protect the affidavit against future procedural challenges regarding informed consent, mental capacity, or lack of linguistic comprehension before foreign judicial or administrative tribunals.

How must physical exhibits and supporting evidence be marked, annexed, and endorsed?

Sworn statements frequently incorporate documentary evidence to substantiate the deponent's factual claims, such as foreign vital statistics, corporate records, financial statements, residential leases, or Thai police clearance certificates. Simply stapling supporting paperwork to a signed jurat page does not satisfy foreign evidentiary standards and routinely leads to document rejection. Every supporting document cited within the affidavit must be designated systematically, such as Exhibit A or Annexure 1. The sworn text must refer explicitly to each marked item, establishing what the document represents, how the deponent acquired lawful custody of it, and whether the attached reproduction is a true, complete, and unalterated copy of an original record examined during execution.

During the appointment, the Notarial Services Attorney inspects the primary physical documents to verify that all appended copies are complete and accurate reproductions. The attorney then marks each exhibit with an endorsement stamp or attaches a separate exhibit endorsement slip, certifying that the item is the specific exhibit identified and sworn to within the deponent's statement. The attorney signs, dates, and impresses their official notarial seal upon every individual exhibit endorsement. For extensive filings, documents are often bound using eyelets or archival ribbons secured with legal wafers to prevent the removal or substitution of pages after signing. Receiving authorities decide acceptance, and applicants must verify in advance whether their destination court imposes specific mechanical binding, margin, or pagination rules.

What legalisation or apostille procedures must follow notarial execution in Thailand?

Executing a sworn statement before a Notarial Services Attorney completes the formal witnessing and oath-taking, but foreign courts, national immigration departments, and public registries often require subsequent authentication of the attorney's official status. In many instances, the document must undergo the traditional consular legalisation chain. Under this procedure, the Notarial Services Attorney's signature and active standing are first certified by the Lawyers Council of Thailand, followed by official legalisation at the Legalization Division of the Department of Consular Affairs under the Ministry of Foreign Affairs of Thailand, and concluded by diplomatic legalisation at the destination country's embassy or consulate in Bangkok. Receiving authorities determine whether this full authentication chain is mandatory before they will admit a Thai-notarised affidavit into evidence or administrative consideration.

Significant procedural changes will modernize this international document pathway in the near future. Thailand acceded to the Apostille Convention on 30 June 2026, and the Convention enters into force for Thailand on 28 February 2027. Consular legalisation remains fully applicable and strictly necessary until 28 February 2027. Once the Apostille Convention takes effect, eligible public documents and certified notarial acts destined for other contracting states can obtain an apostille from Thailand's designated competent authority, eliminating foreign embassy legalisation entirely. The team of 7 Notarial Services Attorneys at Thai Legal & Immigration Consulting Service Co., Ltd., based in Bangkok (Lat Phrao Soi 95) and Khon Kaen, assists deponents with compliant document preparation, with execution and authentication logistics coordinated via LINE @Thailegal.

Related services

• Notarial Services Attorney
• Marriage & Dependent Visa (Non-O)

Frequently asked

Sources & references

1. Lawyers Council of Thailand — checked 2026-11-04
2. Department of Consular Affairs – Legalization — checked 2026-11-04
3. HCCH – Apostille Convention status table — checked 2026-11-04