The following is a guest post by foreign law intern, Yuri Rattanaboonsen. Yuri works with Foreign Law Specialist, Sayuri Umeda, in the Global Legal Research Directorate in the Law Library of Congress.
In Thailand, surnames are generally unique to family lines, and more often than not, we rarely meet a stranger who has the same surname if he or she is not a distant relative.
Before the enactment of the Thai Nationality Act in 1913, which is also known as the Surname Act, surnames were uncommon for the general public. This law required all Thai citizens and permanent residents to register a family surname for the first time. As a result, many families had to create a new surname. One important feature of the law was that each family’s surname had to be unique. (Thai Nationality Act sec.12(5).) If a name was already registered, the family would have to register a different one.
Currently, the Person’s Name Act B.E. 2505 (1962), as amended by the Person’s Name Act (No. 3), B.E. 2548 (2005), governs the rules for personal names in Thailand. It still states “[t]he surname shall not repeat … a registered surname.” (sec. 8(3).)
Thai Surnames
Originally, Thai surnames often reflected a person’s ancestry, place of origin, or occupation, and usually consisted of two to three syllables. They can relate to information about religion, social class, or even links to royalty or heritage.
Thai immigrant families’ surnames are often long. For example, because many Chinese families’ surnames were the same and were already in use, many immigrant families had to modify or expand them to register unique surnames under the 1913 law. Some families chose Thai words that sounded similar to their original Chinese surname. Others created longer surnames by adding extra syllables or translating the original name’s meaning into Thai. As a result, many names and surnames today are long and complex.
The Person’s Name Act limits the length of a surname. It states “[t]he surname shall … not be comprised of more than 10 alphabetical letters….” (Id. sec. 8(5).) This only applies to the Thai alphabet. Therefore, a romanized Thai surname often has more than 10 Roman characters.
It is rare, but some overlap of Thai surnames exists because technology was not advanced enough to detect all registered surnames nationwide at the time the registry was created. The Department of Provincial Administration’s system, which can check the population registration going back to 1984, came online to link data nationwide in 1993. It was then discovered that many people are not relatives but have the same last names.
Name Change
When a surname is changed to a new one, it often becomes quite long. In Thailand, people can change their names for any reason. (Id. sec. 17) Many individuals choose to change their names for personal, cultural, or spiritual reasons.
Some people change names based on astrological beliefs, selecting letters that are thought to be compatible with the individual’s birthday. In these naming calculations, each letter and vowel has a specific meaning. People try to make the total value of their name and surname lucky or strong. To do this, they often need to use more letters, which results in longer names and surnames. However, many people who do not hold these beliefs still have short surnames.
Permission to Use Another Person’s Surname
A Thai person who is not a spouse or relative of another person and who has a different surname can have the person’s surname upon permission of the person who registered the surname. The act states that the permission “can be made by filing an application to the local Registrar in the area where he or she has his or her name on the household registry …The permission … shall be valid only upon the local Registrar’s issuance of a letter showing the permission to use such surname to” a particular person. (Id. sec. 11.)
Romanization of surnames
The same Thai names might be spelled differently in Roman characters on passports or national identity cards due to the different practices in different registrars’ offices. In addition, the registrar’s consideration and opinion affected the registration process. (Id. sec. 18.)
In July 2023, Bangkok Metropolitan sent a letter to the Department of Provincial Administration to discuss the practice of using Roman characters for first and last names on national identity cards. The Department of Provincial Administration responded by stating that a person’s name must be romanized through transliteration based on phonetic principles, as written in the Prime Minister’s Office Announcement of English transliteration criteria on August 26, 1989, and the Royal Institute criteria for transliteration of Thai into Roman letters by phonetic means on January 11, 1999. The Department of Provincial Administration also forwarded this response to all provincial governors to study and practice in the same way. No other specific regulation was made apart from what the Person’s Name Act B.E. 2505 (1962) provides.
Nickname of Thai People
Although it is not officially registered or recognized under Thai law, nicknames are widely used in everyday life. Most Thai individuals receive a nickname at birth. Thai people do not usually change their nicknames; some do, but fewer compared to changes in their first names and surnames. Thais’ nicknames have changed over time. In the past, most nicknames were in Thai, which were short and simple. usually named after animals, fruits, colors, and nature, such as Khao (Rice), Kai (Chicken), Fah (Sky/Blue), and Ploy (Gemstone). Nowadays, the number of syllables increases, and the use of foreign languages in nicknames has increased. Nicknames can be random English words, such as Donut, Golf, or New Year, brand names, such as Porsche, Benz, or Pepsi, or even be an alphabet letter, such as A, B, S, or X.
A person may go by their nickname socially and professionally for their entire life, but only their official given name will appear in legal contracts, government records, and academic certifications. In daily life, individuals are more commonly known by their nickname than their full legal name.
Further Reading
If you would like to know how other countries regulate names, do not forget to check out our other blog posts on that topic, among them, Jenny’s post on naming laws in Germany, Kelly’s post on banning baby names in New Zealand, Laney’s on how many times you can change a name in Taiwan, or Elin’s post on Icelandic name laws.
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