Which carriers matter, what buying a SIM involves, and when an eSIM is the smarter move.
Reliable mobile internet at better prices than most travel eSIMs, with polished iOS and Android apps and support for making and receiving phone calls.
One of the biggest travel eSIM brands, with a very large destination catalog.
Known for unlimited-data plans in many destinations, at a higher price per gigabyte.
The 60-day identity re-confirmation is the main trap for longer stays: miss it and the line stops working. Data-only tourist SIM variants have voice disabled entirely, and there is a 3-SIM-per-brand cap. No VoIP blocking, device registration or tethering restrictions to worry about.
Largest operator with the best-marketed tourist plans and reliable nationwide coverage. Advertised unlimited speeds can fluctuate in practice.
Excellent coverage and particularly strong on the islands: Phuket, Koh Samui, Koh Phangan and Koh Lanta.
Merged into True Corporation in 2023, so it is now the same company and network as TrueMove H.
A passport is required at the point of purchase, and each person can buy at most 3 SIMs per brand. If you keep using a tourist SIM beyond 60 days from activation, you must re-confirm your identity, either by texting your passport number to 4444161 and following the reply link, or in person at a carrier shop, or the line stops working.
Real: AIS's 30-day unlimited costs 1,199 THB (about $38) at the airport against roughly 299 to 599 THB for an AIS Tourist SIM at 7-Eleven or in the city, so buying in town can save 30 to 50 percent or more.
Guac eSIM covers Thailand with data plans starting from $1.50 per GB and instant activation, so your phone is online the moment you land. Airalo and Holafly are popular alternatives.
SIM cards and eSIM in Thailand