Airport exchange rates in Thailand
Exchange counters at Thai airports compared with city rates: Suvarnabhumi, Don Mueang, Phuket, Chiang Mai, U-Tapao and more.
The exchange counters inside Thai airports are the worst place in the country to change a large amount, and the most convenient place to change a small one. Most quote several percent below the counters in the city they serve, on top of a wider spread for anything other than dollars and euros. The pages here put each airport's published counters next to the best rate in its city, so the cost of convenience is a number rather than a feeling.
The practical answer is the same at every airport: change enough for the taxi or train and a first meal, roughly three to five thousand baht, and change the rest in town. The one exception is Suvarnabhumi, where the Superrich Thailand counter on the lower floor by the Airport Rail Link quotes the same rates as its city branches; a reader who lands there can change the whole amount before leaving the building.
Where no counter inside a terminal publishes its rates, the page says so and shows the city benchmark instead, so you can judge the board you are standing in front of.