US Treaty of Amity Company Setup

What the Treaty gives an American investor

The Treaty of Amity and Economic Relations between the Kingdom of Thailand and the United States of America was signed on 29 May 1966 and entered into force on 8 June 1968. Its practical effect is that qualifying American nationals and American-owned companies may hold majority or full ownership of a Thai company and operate in most business sectors on substantially the same basis as Thai nationals, rather than being restricted by the Foreign Business Act B.E. 2542 (1999).

The mechanism is certification rather than exemption by declaration. A company seeking Treaty protection obtains a certification of American ownership through the Commercial Service at the United States Embassy in Bangkok, and then applies to the Department of Business Development at the Ministry of Commerce for the foreign business certificate that records the protection. Until that certificate issues, the company is an ordinary foreign-majority company and is subject to the ordinary restrictions.

Treaty protection attaches to ownership and control, and both are examined. American nationals or American-incorporated entities must hold the majority of shares, and the majority of directors must be American or Thai. Layered holding structures where the ultimate American ownership is real but obscured through several intermediate jurisdictions cause more delay at certification than any other single factor.

Sectors the Treaty does not reach

These reservations are the reason Treaty planning starts with the business objectives rather than the corporate form. An American investor whose model touches a reserved sector will need a different structure — a Board of Investment promotion, a foreign business licence, or a restructuring of the activity — and discovering that after incorporation means doing the work twice. Note also that owning land is not something the Treaty confers; land ownership by foreigners is governed by the Land Code and its narrow exceptions regardless of Treaty status.

• Communications, including telecommunications and broadcasting.
• Transport, including domestic land, water and air transport.
• Fiduciary functions.
• Banking involving depository functions.
• Exploitation of land or other natural resources.
• Domestic trade in indigenous agricultural products, and ownership of land.

The certification sequence

1. Confirm the sector is not reserved: Map every revenue line against the Foreign Business Act lists and the Treaty reservations before choosing the structure.
2. Incorporate the Thai company: Registration with the Department of Business Development, with a share register and director composition drafted for Treaty eligibility from day one.
3. Assemble the ownership evidence: For individual shareholders, US passports. For corporate shareholders, certificates of incorporation, good standing and evidence of American ownership up the chain, notarised and legalised.
4. Obtain the US Commercial Service certification: The Embassy's Commercial Service reviews the ownership documentation and issues the certification letter used in the Thai application.
5. Apply to the Department of Business Development: Application for the foreign business certificate under Treaty protection, supported by the Embassy certification and the corporate documents in certified Thai translation.
6. Maintain eligibility: Share transfers, board changes and new business activities can affect protection. Any change in the ownership or control profile should be assessed before it is executed.

Documents from the United States and the legalisation chain

Corporate documents issued in the United States must be authenticated before Thai authorities will rely on them. The conventional chain is notarisation, then authentication by the Secretary of State of the issuing state, then endorsement at the Royal Thai Embassy or Consulate in the United States, followed by certified Thai translation and certification by the Department of Consular Affairs in Bangkok. Thailand's accession to the Apostille Convention takes effect on 28 February 2027; until that date the embassy endorsement step remains necessary rather than replaceable by an apostille.

Translation consistency is not cosmetic here. The company's registered Thai name, its English name, the shareholders' names and the directors' names must be rendered identically across the DBD filings, the Embassy certification bundle and every translated corporate document. A director whose middle name appears in one document and not another is a routine cause of a request for clarification, and each clarification round adds weeks to a certification that otherwise moves predictably.

Common mistakes and how we avoid them

More questions we are asked

Can a US permanent resident who is not a citizen qualify?

Treaty protection turns on American nationality for individuals and American ownership for entities. Permanent residence is not nationality, so a structure relying on it should be reviewed before filing.

Does Treaty status remove the need for work permits?

No. Work permits and visas are governed separately, and the company must still satisfy the applicable capital and employment conditions for the foreign staff it wishes to employ.

How long does certification take?

It depends primarily on how clean the ownership documentation is and on the Embassy and DBD queues. Files with a single-layer American ownership structure and complete legalised documents move fastest.

What happens if American ownership falls below the majority?

Protection depends on continuing eligibility. A transfer that changes the ownership profile should be assessed before completion, because losing protection retrospectively is far harder to manage than planning the transfer.

What do you handle?

Structuring advice against the reservations, incorporation, preparation and legalisation of the US corporate documents, certified Thai translation, the Embassy certification bundle and the DBD application.