The best price found from United States to Chiang Mai is on May 9th, 2018, travelling with Etihad Airways. See more options, compare prices and book: search flights.
Domestic and international flights arrive and depart from Chiang Mai International Airport, 3km southwest of the old city.
Schedules vary with the seasons and tourist demand. Tickets to Bangkok start at around 1200B. Heading south, expect to pay from 2400B to Phuket, 1650B to Surat Thani. The bulk of the domestic routes are handled by the following airlines:
Direct flights linking Chiang Mai to neighbouring nations are also expanding fast, with regular flights to Kuala Lumpur (Malaysia), Yangon (Myanmar) and destinations around China. Lao Airlines has direct flights to Luang Prabang and Vientiane. Less frequent services include Dong Hoi (Vietnam, transfer to Ho Chi Minh City). To reach Cambodia, you'll have to go via Bangkok.
The airport has luggage storage (7am to 9pm, 200B per day), a post-office branch (8.30am to 8pm), banks, souvenir shops and a tourist assistance centre. If you have time to kill, you could just stroll back down the highway to the large Central Airport Plaza.
SM Travel in the old city is a good place to book flights.