Expat in Thailand: A Comprehensive Legal Guide for Expats with Benoit & Partners

Understanding the Legal Framework for Expat in Thailand

The Thai Legal System and Civil Law Tradition

Thailand’s legal structure is rooted in the civil law tradition, heavily influenced by European codified systems. It does not follow case-law precedent as in common law countries; instead, it is governed primarily by written statutes. These include the Civil and Commercial Code, the Penal Code, the Revenue Code, and a wide array of administrative laws and ministerial regulations.

The Civil and Commercial Code (CCC) is divided into six books and governs essential aspects of private law: persons, family, succession, property, obligations, and specific contracts. Foreigners residing in Thailand become subject to its provisions, particularly in matters of leases (Section 537 et seq.), contracts (Section 369 et seq.), family matters (Section 1435 et seq.), and inheritance (Section 1599 et seq.).

The Thai Constitution does not afford foreign nationals the same guarantees as Thai citizens, especially in areas of property rights and business ownership. As such, many legal pathways available to Thai nationals are restricted or modified for expat in Thailand. This legal asymmetry must be carefully accounted for when planning long-term residence or commercial activity.

Immigration Law: The Legal Basis for Entry and Stay 

The Immigration Act B.E. 2522 (1979) is the cornerstone of Thai immigration law. It grants broad powers to the Immigration Bureau, including discretion to approve or deny entry, set visa categories, and impose conditions on stay. Foreigners who wish to enter the country must apply for a visa in accordance with Ministerial Regulations issued under this Act.

The most common categories for expatriates include the Non-Immigrant B visa (for employment or business), the Non-Immigrant O visa (for marriage, retirement, or family dependency), and the increasingly popular SMART Visa, launched under the Ministry of Labour and BOI framework to attract investors and skilled professionals. Each category carries its own legal implications regarding rights of residence, employment, and renewal conditions.

Visa overstays, failure to report address changes (Section 38), or performing work without a proper permit (Section 37) can lead to deportation or blacklisting. Legal compliance is not optional: it is monitored and enforced, often through spot inspections and reporting obligations.

Benoit & Partners advises expat in Thailand from the beginning of their relocation project, selecting the optimal visa type, preparing required documentation, and following up with immigration authorities. For high-level professionals, retirees, and digital workers, the firm’s familiarity with recent reforms (such as the LTR Visa and updates to tax remittance rules) provides critical legal clarity.

Restrictions on Foreign Ownership and Business Activities

The Foreign Business Act B.E. 2542 (1999) defines three categories of restricted business activities. List One is strictly prohibited to foreigners; Lists Two and Three require a Foreign Business License (FBL) or promotional privileges from the Board of Investment. The definition of a “foreign company” under Section 4 of the Act is also crucial: a company with over 50% foreign shareholding is considered foreign even if registered in Thailand.

Operating without a license in a restricted sector may lead to imprisonment up to three years and fines up to THB 1 million, under Section 36. This is why many expatriates opt to apply for BOI promotion or restructure ownership using legal tools such as preferential share classes or joint venture agreements—measures which must be carefully drafted to avoid sham structures or nominee arrangements.

Benoit & Partners provides due diligence and strategic structuring to ensure that foreign clients are fully compliant with these ownership regulations while preserving control over their business.

Tax Law: Becoming a Thai Tax Resident

Thailand’s Revenue Code determines tax residency based on physical presence. According to Section 41, any individual who stays in Thailand for 180 days or more in a calendar year is subject to Thai income tax on worldwide income. This provision applies regardless of whether the income is earned or remitted during the same year.

The remittance principle—particularly controversial among expats—was clarified in Revenue Department Order No. Por. 161/2566 issued in 2023, which exempts foreign income earned in previous years and remitted after one year. For expat in Thailand with foreign investments, pensions, or remote work income, this rule is critical and often misunderstood.

The tax rates are progressive, ranging from 5% to 35%, and foreign taxpayers are required to file annual returns using the PND 90 or PND 91 form, depending on income type. Failure to file may trigger penalties of up to 100% of unpaid tax plus surcharges.

Benoit & Partners assists expat in Thailand in evaluating their tax residency, planning income remittances, and accessing double taxation treaties (DTTs), especially with France, the United States, Germany, and other major jurisdictions.

Visa and Immigration Regulations for Expat in Thailand

Entering the Kingdom as Expat in Thailand: Legal Entry Conditions for Foreign Nationals

For every Expat in Thailand, legal entry into the country begins with a valid visa. Under the Immigration Act B.E. 2522 (1979), foreign nationals must possess a passport or travel document and obtain the appropriate visa before arrival, unless exempted by bilateral agreements or visa-on-arrival policies.

The Immigration Act grants broad discretion to the immigration authorities. In particular, Section 12 empowers officers to deny entry to individuals deemed threats to national security, health, or morality, or to those unable to demonstrate sufficient financial means. Additionally, Section 18 authorizes the Director-General to set the type, duration, and conditions of stay for each visa.

While tourist visas remain widely used for short-term stays, they do not permit employment or business activities. Engaging in such activities without the appropriate visa and work permit constitutes a criminal offense under the Alien Employment Act B.E. 2521 (1978).

Non-Immigrant Visas: Categories and Conditions for expats in Thailand 

The most common visa type for expatriates is the Non-Immigrant Visa, divided into several subcategories, each governed by ministerial regulations and administrative practice. The main subcategories relevant to expatriates include:

Non-Immigrant B (Business) – This visa is required for employment or business activity. It typically requires a sponsorship letter from a Thai company and evidence that the company is properly registered and operating. After arrival, the visa must be followed by an application for a work permit, in accordance with the Alien Employment Act.

Non-Immigrant O (Other Purposes) – This category includes spouses of Thai nationals, dependents, retirees, and volunteers. While it allows long-term residence, it does not always permit work. Spouses of Thai nationals may work only if they hold a valid work permit under a Non-B visa or if they are granted permission under special exemptions.

Non-Immigrant O-A and O-X (Retirement Visas) – Designed for retirees over 50 years old, these visas require minimum financial thresholds: THB 800,000 in a Thai bank account, or a monthly income of THB 65,000, or a combination. The O-A visa is valid for one year, while the O-X is valid for ten years, subject to reporting obligations and annual renewals. Retirees must also obtain private health insurance with minimum coverage amounts set by the Ministry of Public Health.

Non-Immigrant ED (Education) – While typically reserved for students, this visa has been used by expatriates enrolled in Thai language schools. However, authorities have tightened the rules to combat abuse, requiring real attendance and certification.

LTR Visa (Long-Term Resident) – Announced in 2022 and governed by BOI Notification No. 9/2565, this visa targets four categories: wealthy global citizens, retirees, professionals working remotely from Thailand, and highly-skilled professionals. The LTR Visa grants up to ten years of residence and includes tax benefits and simplified reporting obligations. However, strict income and asset thresholds apply, along with a health insurance requirement.

The Destination Thailand Visa (DTV), introduced in 2024 under Ministerial Regulation No. 405, offers a legal framework for remote workers and digital nomads wishing to reside in Thailand while working for foreign companies. Issued under the Immigration Act B.E. 2522 (1979), it grants a 5-year multi-entry visa, with the possibility of extension up to 10 years, and allows stays of 180 days per visit.

Applicants must be 20 to 55 years old, show an income of USD 80,000 per year (or USD 40,000 with advanced qualifications), hold health insurance of at least USD 50,000, and prove remote employment or ownership of a foreign company.

Crucially, the DTV Visa does not permit work for Thai employers or participation in restricted business activities under the Foreign Business Act B.E. 2542 (1999). Violating these conditions may constitute unlawful employment under Section 8 of the Alien Employment Act B.E. 2521 (1978).

Benoit & Partners regularly advises clients on visa selection, depending on their professional goals, income, and family status. The firm also coordinates with BOI and immigration officers to structure applications that reflect both the letter and the spirit of the law.

Work Permits: The Legal Right to Work for an Expat in Thailand

Foreign nationals cannot engage in any employment in Thailand without a valid work permit, as stated under Section 8 of the Alien Employment Act B.E. 2521 (1978). “Work” is broadly defined to include both paid and unpaid activity. Even volunteer work or participation in business meetings may, in some cases, be considered “work” under Thai law.

Employers must demonstrate that the position could not be filled by a Thai national, and must meet minimum requirements including paid-up capital and proper registration with the Ministry of Labour. For each foreign employee, the company must have:

• At least THB 2 million in registered capital;
  
• At least four Thai employees per foreigner hired;
• A business license and tax filings up to date.
  

Exemptions exist for BOI-promoted companies, foreign press, treaty nationals (e.g., under the U.S.-Thailand Treaty of Amity), and certain experts. However, these are granted case-by-case and require careful compliance.

Work permits are issued for one year and tied to the employer. A change in employment requires a new permit. Violating permit conditions, such as working for a different entity or outside the permitted role, can result in imprisonment (Section 51) and fines up to THB 100,000.

Benoit & Partners ensures that expatriates and their employers comply with the Alien Employment Act. The firm handles work permit filings, employment contract preparation, and liaises with the Labour Office during inspections or renewals.

90-Day Reporting and Address Compliance 

Under Section 37(5) of the Immigration Act, every foreigner residing in Thailand for more than 90 consecutive days must report their address to the Immigration Bureau. This is known as “90-day reporting.” Failure to comply results in fines and may complicate future visa renewals.

In addition, Section 38 requires landlords (or hotel managers) to report the presence of foreign tenants within 24 hours of their arrival. Many landlords are unaware of this requirement, placing the burden on the tenant to ensure legal compliance.

Benoit & Partners educates expatriates on these obligations and helps set up compliant rental agreements or corporate leases to avoid exposure during immigration audits.