1. Nok Air is a budget carrier under Nok Airlines Public Company Limited and a part of the New Value Alliance. Air was established in February 2004 under the name Sky Asia Limited which changed to Nok due to its entry preparation to the Stock Exchange of Thailand. Nok Air started operations on 23 July 2004 and began its first international service on 31 May 2007. All Nok Air flights operate from Bangkok's Don Mueang International Airport.
The word Nok means bird in Thai which symbolizes freedom, air travel, and friendliness. In the World Airline Awards 2018 based on Skytrax, Nok Air won 1st place in Best Low-Cost Airline out of 4 Low-cost Airlines in Thailand. Nok Air also ranked 20th place in the World’s Best Low-Cost Airlines out of 335 airlines covered in the survey results.
2. Bangkok Airways, formerly known as Sahakol Air, was found in 1984 by Dr. Prasert Prasarttong-Osoth and began services in 1986. It became the first privately owned domestic airline in Thailand and eventually became Bangkok Airways in 1989. In the same year, opened its own airport in Koh Samui, its second airport in Sukhothai in 1996, and its third in Trat in March 2003.
Bangkok Airways has been awarded World's Best Regional Airline Award and Best Regional Airline in Award in World Airline Awards 2018 by . It offers a higher level of service than most other airlines — and often with a higher price as well. Bangkok Airways operates scheduled services to destinations in , , , Hong Kong, , , , , , , and with Airport as its main base.
3. Thai is a lower-cost airline managed by Thai Airways servicing many destinations throughout Asia and is a member of Star Alliance.
Thai Smile started on 20 May 2011 when the board of Thai Airways announced plans to create a new low-cost carrier, which at the time was called Thai . Thai Smile began its operation in 2012. Thai Smile is intended to serve the market gap between low-cost carriers and full-service airlines.
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