thThai League 1

Club from Ayutthaya, the historic former capital of the Siamese kingdom.

Club from Pathum Thani province in the Bangkok metropolitan area, competing under the name True Bangkok United.

Club from Pathum Thani province, playing at True BG Stadium and associated with the Bangkok Glass company.

Club from Buriram, by far the most dominant team in Thai football in recent years, playing at the Chang Arena.

Club from the northern Thai city of Chiang Rai near the borders with Myanmar and Laos, competing as Singha Chiangrai United.

Club from the coastal city of Chonburi on the Gulf of Thailand, nicknamed the Sharks.

Club from the northern Thai province of Lamphun, promoted to the top flight in 2022.

Club from the southern Thai province of Pattani — a 2026/27 Thai League 1 newcomer, in the top flight for the first time in its history.

Club from the Khlong Toei port district of Bangkok, a traditional name in Thailand's top flight.

Club from the coastal town of Prachuap Khiri Khan on the Gulf of Thailand.

Club from the Rasi Salai district of Sisaket province — a newcomer, promoted to the top flight for the first time as second-tier champions.

Club from Ratchaburi province, nicknamed the Dragons, playing at Dragon Solar Park.

Club from the industrial province of Rayong on Thailand's eastern seaboard.

Club from Sisaket province, promoted to Thai League 1 after a 14-year wait since its founding.

Club from Sukhothai, the historic capital of the first Thai kingdom.

Club from Uthai Thani province, founded in 1937 and one of the oldest clubs in the country.