What To Know About Branch Office in the context of company, tax, legal and expat services in Thailand?

Branch Office: what matters in practice

This question sits inside company, tax, legal and expat services in Thailand, where company formation, accounting and tax, legal advisory and expat support is assessed purely from documents. Establish the receiving authority's requirement first, then build the file in the order that authority expects.

Where a stage is handled by a different office, the earlier certification has to be visible on the document itself. Officers verify a chain, not an assurance.

How company, tax, legal and expat services in Thailand works

Any foreign-issued corporate document (certificate of incorporation, board resolution, power of attorney, passport copy) must normally be notarised abroad, legalised or apostilled, then translated into Thai and certified before a Thai registrar will accept it.

Corporate filings in Thailand are split across several regulators. Incorporation and registered-object changes sit with the Department of Business Development, tax registration and filings with the Revenue Department, investment privileges with the Board of Investment, and work authorisation with the Department of Employment. A document accepted by one of them is not automatically accepted by another.

Foreign shareholding is governed by the Foreign Business Act, with separate treatment for BOI-promoted companies and for US nationals under the Treaty of Amity. Structure decisions therefore have to be made before incorporation, because changing them later means re-registering objects, capital and sometimes the work-permit quota.

Where Branch Office fits in the document chain

Documents connected with Branch Office move through a fixed chain: issuance, translation, certification and acceptance. Each link is verified against the previous one, which is why a missing intermediate stamp cannot be repaired at the final counter.

Because company formation, accounting and tax, legal advisory and expat support is assessed on paper, the safest working method is to prepare the complete set before approaching any office, then submit once with everything attached.

Evidence the reviewing officer looks for

An officer checks four things: that the original is authentic and current, that the translation is complete, that the certifications appear in the correct order, and that the person submitting is entitled to do so.

None of those four is a formality. A file that satisfies three of them is still returned, and the queue restarts from the beginning.

Working with IVC

IVC has handled company formation, accounting and tax, legal advisory and expat support since 2011 - more than fourteen years of files across translation, notarisation, consular certification and submission support. We prepare, check and track the chain; the decision always remains with the authority, and we never promise an outcome.

Fees depend on document type, language pair, volume and urgency, so they are quoted by our staff rather than published. Contact us by phone, LINE or email with a scan of the document and the destination, and you will get a written scope before anything starts.

Pre-submission checklist

• Keep the certification order: issuer, translator, consular authority, embassy
• Check validity dates on every supporting document on the day of submission
• Carry identity documents for every named party and for the representative
• Keep receipts and reference numbers for each stage
• Scan the complete file exactly as submitted
• Allow for public holidays at each office in the plan
• Confirm in writing what the receiving authority accepts today

Common pitfalls

• Relying on an outdated checklist instead of the issuing authority's own page
• Submitting through a representative whose authority has expired
• Letting a passport change break the match with an issued document
• Splitting a document set between offices and losing an intermediate stamp
• Treating one authority's acceptance as binding on another

Official sources

• Department of Business Development — Company registration
• The Revenue Department — Tax registration and filing
• Thailand Board of Investment — Investment promotion
• Department of Consular Affairs, Ministry of Foreign Affairs (Thailand) — Legalisation and Apostille services
• HCCH — Apostille Convention status table

Information reviewed as of August 2026.