Applying for Thai Citizenship: Key Considerations and Legal Guidance 

Applying for Thai citizenship involves meeting a set of stringent criteria designed to ensure applicants’ good integration into Thai society.  

The Nationality Act BE 2551 (2008) mainly governs Thai citizenship and provides three main routes to acquire it:  

  1. By birth (ius sanguinis),  
  2. through naturalization based on residence, employment, marriage to a Thai citizen, having children with a Thai citizen, or academic ties (like graduating from a Thai educational institution), and  
  3. by reacquisition after renouncing it. 

The following will focus on the second route, naturalization, and explain its requirements: 

A. General Criteria for Naturalization

To qualify for naturalization, applicants generally need to: 

  • Be at least 20 years old.
  • Have clean conduct records.
  • Demonstrate five years of domicile in Thailand or hold a non-immigrant visa for the same period.
  • Show proficiency in the Thai language. 

B. Specific Criteria Depending on Grounds for Naturalization

Additional requirements apply based on specific circumstances, such as 

  • Employment: Applicants must demonstrate a monthly income of at least 100.000 THB, have held an uninterrupted work permit for three years, and provide proof of personal tax income payments; or 
  • Marriage: Applicants must have had an uninterrupted stay extension in Thailand for three years, and their monthly income should be at least 50,000 THB. A marriage with children must have lasted for one year, without children for three years at the time of application; or 
  • Other relations to Thailand: Applicants who have a child with a Thai citizen or have graduated from a Thai educational facility must provide proof of personal tax income for the past three years and have a monthly income of at least 50.000 THB.

In all cases, it is necessary to provide evidence of a certain monthly or annual income, as well as tax payments, along with a certain time span of uninterrupted residence and/or holding a work permit. The amount of these sums varies depending on the application’s starting point.

C. Formal Application Requirements

Each application type has specific forms and documentation requirements, including personal tax income proof, employment certification, and copies of relevant certificates and documents depending on the grounds of the application. 

Applicants must present all original documents in person, along with an application fee of 5,000 THB. Bangkok residents should visit the Special Branch Bureau, residents outside of Bangkok should apply to the Provincial Police, and people outside of Thailand should go to their Thai embassy or Royal Thai consulate.  

The documents will be sent to the relevant authorities for checking and presented to higher-ranking officers. The Interior Minister has the final authority to make the decision. 

There is no exact timetable for consideration as it depends on the length of the official review process, which can take approximately 2-3 years. Few applications are received, and even fewer are accepted. In 2020, 44 received approval from the Minister of Interior. In 2021, 54 women were granted Thai citizenship based on marriage to a Thai citizen. 

Male applicants should be aware of the potential for military conscription in Thailand following their nationalization.

D. Dual Citizenship

Dual citizenship is allowed in Thailand, but only in certain cases. Depending on the case, applicants may need to provide a letter of intent to renounce their former citizenship.

It is important to note that in some cases, the citizenship in their home country expires automatically. More and more countries allow dual citizenship, but the legal implications of a new citizenship application for the original citizenship should always be considered very carefully.

Contact us today, and let our professional team guide you through the process of obtaining Thai citizenship.

About the Writer

Fabian Doppler

Fabian is a founding partner of FRANK Legal & Tax. He focuses his practice on corporate / commercial and real estate law, as well as litigation. He is admitted to the Bar of Stuttgart, Germany, where he actively practiced law before coming to Thailand in 2005.

Fabian Doppler