eSIM for Thailand: Networks, SIM Rules and Island Coverage

Yes — a travel eSIM works across Thailand, on the country’s main networks. Our Thailand eSIM connects to AIS and TrueMove H. The big advantage over an airport SIM is time: since 2025, Thai SIM cards for foreigners must be registered with a passport in person, while an eSIM is bought online and installed before you fly.

Which networks does an eSIM use in Thailand?

Thailand has two big operators: AIS and True. True merged with dtac in March 2023 to form True Corporation, and both brands still run. In Opensignal’s August 2026 report, dtac and True jointly won Best Network while AIS took the most awards overall — in practice, both are strong in cities and tourist areas, and more than 97% of connections are on 4G or 5G. Our Thailand eSIM can use AIS and TrueMove H.

Thailand’s SIM registration rules for tourists

Thailand has tightened SIM rules to fight phone scams. Under rules published in August 2025 and amended in May 2026, a Thai SIM for a foreigner needs your passport, must be registered in person at a shop or authorised dealer, is limited to three SIMs per operator, and tourist SIMs last at most 60 days. Incoming international calls on Thai numbers are also tagged so they can be flagged as possible scams. None of that matters if you buy a travel eSIM online before you go — you skip the shop counter entirely.

eSIM vs an airport tourist SIM

Prices checked 9 October 2026 (AIS tourist plans are also sold for 8, 15 and 60 days; True’s Tourist SIM starts at 449 THB for 8 days). A tourist SIM makes sense if you want a Thai number; for most trips an eSIM is quicker and keeps your home number working.

Coverage: Bangkok, the islands and the north

• Bangkok: excellent across the city. The BTS Skytrain runs above ground, and the MRT’s underground stations have mobile coverage.
• Islands: Phuket, Koh Samui, Koh Phangan and Koh Phi Phi are well covered (Phi Phi can get congested in peak season). Smaller islands such as Koh Lipe can be slower, and signal drops on longtail boat trips.
• The north: Chiang Mai and Chiang Rai are well covered; mountain roads and national parks can be patchier.

Arriving: airports and free Wi-Fi

Bangkok has two airports — Suvarnabhumi (BKK) and Don Mueang (DMK) — and Phuket (HKT) and Chiang Mai (CNX) are the main others. All are run by Airports of Thailand and offer free Wi-Fi, but sessions are time-limited. With an eSIM installed at home, you can book a Grab before you reach the taxi queue.

Apps you’ll want data for

• Grab and Bolt — both officially recognised ride-hailing apps, and usually cheaper and easier than flagging a taxi.
• Maps and translation — download Thai for offline translation.
• Payments — Thailand’s PromptPay QR codes are built for Thai bank accounts, but tourists can pay them through apps such as TAGTHAi Easy Pay; cards work in most hotels and malls.

Set up your Thailand eSIM

1. Buy a Thailand plan — or an Asia plan if you’re also visiting Vietnam, Cambodia or Malaysia.
2. Install it at home on Wi-Fi; validity starts when you first use data.
3. When you land, set the eSIM as your mobile data line and turn on data roaming for it.

How much data do you need in Thailand?