Treaty of Amity in Thailand.
Under the 1966 Treaty of Amity and Economic Relations, US citizens and US-majority entities can own 100% of a Thai company in most sectors — without BOI promotion or a Foreign Business License.
What is the Treaty of Amity?
The Treaty of Amity and Economic Relations between the United States and Thailand, signed in 1966 and still in force, gives qualifying US businesses a status no other foreign nationality enjoys in Thailand.
Under it, a company majority- or wholly-owned by US citizens or US entities is treated, in most commercial sectors, much like a Thai company — and is exempt from most of the restrictions of the Foreign Business Act. That means American investors can hold full control without a Thai partner, without BOI promotion, and without the discretionary Foreign Business License other foreigners need. In place of that license, a Treaty company is issued a Foreign Business Certificate confirming its protection.
What the Treaty does — and doesn't do.
The Treaty is powerful, but bounded. These are the three things worth fixing in your mind before you plan around it.
What it grants
Majority or 100% US ownership across most commercial sectors with no Thai partner, treatment broadly equal to a Thai company, protection against nationalisation and expropriation, and access to dispute-resolution mechanisms.
What setting up requires
A unique company name and a Thai registered address, at least two shareholders (US-majority at every tier), a board where the majority of directors with signing authority are US and/or Thai citizens, around THB 3 million in capital for a restricted activity, US Commercial Service certification, and the Foreign Business Certificate from the Ministry of Commerce.
Where it doesn't reach
Land ownership and several reserved sectors stay off-limits — communications, transport, fiduciary functions, deposit-taking banking, exploitation of land and natural resources, and domestic trade in indigenous agricultural products. The Treaty also carries no tax holiday — for that, BOI promotion is the route.
Why US investors use it — and what it takes to set up.
The benefits are real, and so is the checklist. Here is both side by side.
Advantages
- Up to 100% US ownership with no Thai partner required
- Treatment broadly equal to a Thai company across most sectors
- Protection against nationalisation and expropriation, plus access to dispute resolution
- A simpler, faster path than the discretionary Foreign Business License other foreigners face
What you need to register
- A unique company name and a local registered address
- At least two shareholders, US-majority at every ownership tier
- A majority of the directors with authority to bind the company must be US and/or Thai citizens — in practice we recommend planning around US-citizen signing directors, the reading the registrar applies most strictly
- Around THB 3 million in capital for a restricted activity
- The Foreign Business Certificate, with activities set out in the articles of association
Who qualifies — and where the check is strict.
The Treaty's protection turns entirely on ownership and control being genuinely American. The US Commercial Service at the embassy verifies this before the Ministry of Commerce will issue the certificate.
- US citizens, and entities majority-owned by US citizens or US-incorporated companies, qualify; US majority must hold at every tier up to the ultimate parent.
- A majority of the company's directors must be US or Thai nationals.
- Mixed-nationality founders need careful structuring to keep the US majority intact.
- Treaty vs BOI: BOI adds tax holidays the Treaty does not; where the activity fits a BOI category, BOI is often the stronger choice, while the Treaty is faster and broader in sector coverage.
Setting up a Treaty company, step by step.
From incorporation through US-side certification to switching on visas — the sequence a Treaty company follows.
Incorporate the company
The name, memorandum and articles are registered and the DBD issues the certificate of incorporation with the Treaty-compliant ownership structure in place.
US Commercial Service certification
Proof of US ownership is notarised and certified through the US Commercial Service at the US Embassy in Bangkok — individual shareholders via passport documents, corporate owners via certified corporate records.
Foreign Business Certificate
With the embassy letter in hand, the FBC is filed with the Ministry of Commerce; the company cannot trade as a foreign-majority business until it issues.
Bank account & VAT
A corporate bank account is opened, and VAT is registered with the Revenue Department where turnover exceeds THB 1.8 million.
Staff, social security & permits
Employees are enrolled with the Social Security Office, and visas and work permits are arranged for foreign directors and staff.
How we help you set up a Treaty company.
The Treaty of Amity gives US citizens and US-owned companies a status no other foreign nationality enjoys: the right to incorporate a Thai company they majority-own, in most commercial sectors, without applying for BOI promotion or an FBL.
But the qualification check is strict. The core requirement is US-majority ownership and control: US citizens or US-incorporated entities must hold the majority of shares at every tier up to the ultimate parent, and a majority of the directors must be US or Thai nationals. We prepare the supporting documentation, have it certified by the US Commercial Service at the US Embassy in Bangkok, and then file with the Ministry of Commerce for the Foreign Business Certificate that confirms Treaty protection.
There are sector exceptions — communications, transport, fiduciary functions, deposit-taking banking, land and natural resources, and domestic agricultural trade are excluded from the Treaty even with US ownership. We confirm fit before starting.
What we do
- US-ownership eligibility review
- US Embassy notarisation and certification of shareholding documents
- Foreign Business Certificate (FBC) application at the Ministry of Commerce
- Coordinated Thai-company incorporation
- Tax, VAT, and work-permit setup
- Annual Treaty compliance review
What you get
- End-to-end from US-side certification through Thai filing
- Coordinated with US-side counsel if your US parent company is involved
- A one-off certification — no ongoing commitment required
How we work
Eligibility review
Confirm US citizenship of shareholders and directors, and that the proposed activity is within Treaty-protected sectors.
US Embassy certification
Notarised proof of US nationality through the US Embassy in Bangkok.
Company incorporation
Standard Thai company incorporation with the Treaty-compliant ownership structure.
FBC application
Foreign Business Certificate filed with the Ministry of Commerce to formalise Treaty protection.
Post-grant setup
Tax registrations, VAT, work permits, and bank account introductions.
Speak with our team
Send a message — typical response within one hour during office hours.
WhatsApp +66 95 332 2447 Send an Enquiry Call +66 2 026 0600Frequently asked
Who qualifies for the Treaty of Amity?
US citizens and entities majority-owned and managed by US citizens or US-incorporated companies. Mixed-nationality founders need careful structuring.
Which activities are excluded?
Communications, transport, fiduciary functions, banking involving deposit-taking, exploitation of land or natural resources, and trade in indigenous agricultural products.
How long does the Treaty process take?
Allow 6–10 weeks total from start to FBC issuance — most of which is the US Embassy and Ministry processing time. The Thai incorporation itself is quick.
Treaty vs BOI for US citizens — which is better?
BOI gives tax holidays and other benefits the Treaty doesn't. If your activity fits a BOI category, BOI is often the stronger choice. Treaty is faster and broader in sector coverage but doesn't provide tax incentives.
Reviewed by the Khonsu Legal team · 1 July 2026
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