Thai Airways Company was the domestic flag carrier of Thailand. Its main base was the domestic terminal at Don Mueang International Airport, then known as Bangkok International Airport. In 1988 Thai Airways merged to become Thai Airways International.
Siamese Airways was the domestic flag carrier of Thailand in 1947. The Government of Thailand had a resolution in 1951, merged with Pacific Overseas Airline (Siam) (POAS), and changed name to Thai Airways Company Limited (TAC). It also called Thai Airways. Thai Airways established the international flag carrier in 1960, Thai Airways International Company. In 1988, Thai Airways Company Limited (TAC) merged with Thai Airways International.