How to get mobile data in Thailand

Thailand is one of the few countries where buying a SIM at the airport is genuinely competitive. The catch is passport registration, a 60-day ceiling, and an hour of your first day.

Daniel de NieuweOct 23, 20265 minute read

Thailand is one of the few countries where buying a local SIM at the airport is genuinely competitive. Tourist SIMs are cheap, sold around the clock at arrivals, and come with unlimited data. The catch is passport registration, a 60-day ceiling that cannot be extended, and an hour of your first day. For most trips a travel plan for Thailand installed at home still wins, but the margin here is narrower than almost anywhere else.

The honest comparison

	Local tourist SIM	Travel eSIM
Price	Cheap, roughly 499 to 1,199 baht depending on duration	Comparable, often slightly more
Where you get it	Airport counter on arrival	Your sofa, before you fly
Time cost	20 to 60 minutes, depending on the queue	Five minutes
Passport required	Yes, mandatory registration	No
Your own number	Lost, unless your phone runs two lines	Kept
Maximum duration	60 days, no extension	Whatever you bought
Covers other countries	No	Regional plans do

Thailand is the one destination where "just buy a SIM when you land" is a real answer rather than a thing people say.

Which makes it worth being specific about when it is the better answer and when it is not.

What a local SIM involves

Registration is mandatory. Every SIM must be registered against your passport. Counter staff do it in a few minutes. You may hold up to three numbers per operator.

Since August 2025, tourist SIMs expire at 60 days and cannot be extended by topping up. For a long stay this matters: at the two-month mark you start again.

Buy it at the airport, not at 7-Eleven. Convenience stores sell top-up credit, not the tourist SIM itself.

Where the counters are:

Airport	Where
Suvarnabhumi (BKK)	Arrivals, 2nd floor, near gates 4, 5, 6 and 10. True counters open around the clock, AIS in the same hall
Don Mueang (DMK)	International arrivals, exits 3, 4 and 6
Phuket (HKT)	Terminal 2, next to exit 3
Chiang Mai (CNX)	Near exit 10

Which network, if you go local

Two operators matter. True merged with dtac in 2023 and the two now run one network, so the practical choice is AIS or True.

	Strength
AIS	Better coverage and consistency, particularly on the islands, in Khao Sok and in the northern mountains
True	Faster average download speeds and wider 5G in the cities. Strong in Bangkok, Chiang Mai, Phuket

The split follows the itinerary. Island-hopping and national parks point to AIS. A city-based trip points to True. If you are doing both, AIS is the safer default, because a slow connection on Ko Lanta beats no connection.

Indicative tourist pricing, both operators: around 499 baht for 8 days, 699 for 15, 1,199 for 30, with unlimited data. AIS also sells a 1-day option and a 60-day one; True sells a 10-day data-only SIM. Prices move and operator pages contradict their own FAQs, so treat these as the shape rather than the quote.

When the local SIM is right, and when it is not

Go local if: you are staying three weeks or more, you are mostly in one country, and an hour on arrival does not bother you. The economics genuinely favour it.

Go with a travel plan if: your trip is under two weeks, you are landing late at night, you are continuing to Vietnam, Cambodia or Japan afterwards, or you want your own number live the moment you switch the phone on. Thailand's airport counters are good, but they are still a queue after a long-haul flight, and a 60-day ceiling plus registration is friction a plan does not have.

Go with a regional plan if Thailand is one stop in a Southeast Asia itinerary. The trade-offs between the two are set out in regional vs local. A Thai SIM stops at the border, and the border is a few hours from most places you will be.

What you will actually use data for

Thailand is a high-usage destination compared with somewhere like Japan, for three reasons.

Ride-hailing constantly. Grab is the default for getting around cities and it needs a live connection for the whole journey, not just the booking.

Maps in places with no street addresses. Pins rather than addresses is the norm. You will be navigating by map far more than by name.

Messaging with everyone. Hotels, tour operators, boat transfers and drivers all run on messaging apps. Confirmations arrive there, not by email.

Add the beach photos, and a standard week here uses more than a standard week in Europe. Size up rather than down.

Coverage, honestly

Cities and main tourist areas are well covered on either network. Beyond that:

Islands vary. The big ones are fine. Smaller ones and the boat rides between them have gaps, and AIS handles these better.
National parks and the northern mountains have real dead zones. Download offline maps before you go in.
Long-tail boat transfers will drop you entirely. Screenshot your booking rather than planning to open it.

What to do

Decide by trip length. Under two weeks, or multi-country, use a travel plan. Three weeks or more in Thailand alone, price a local SIM.
If using a plan, install it at home and let it start when you arrive.
If going local, bring your passport to the counter and expect to lose your own number for the trip unless your phone takes two lines.
Download offline maps for the islands and any national park on the itinerary.
Size the plan up. Grab, maps and messaging run all day here.

Key facts

Passport registration is mandatory for a local SIM. Up to three numbers per operator.
Since August 2025, tourist SIMs last a maximum of 60 days and cannot be extended.
Buy at an airport counter, not a convenience store. 7-Eleven sells top-ups only.
AIS for islands and the north. True for city speed and 5G.
Around 499 baht for 8 days to 1,199 for 30, unlimited data, on either operator.
Thailand is a high-usage destination. Ride-hailing and maps run all day.
A Thai SIM stops at the border. For a Southeast Asia loop, go regional.

Sources

Baht prices and validity periods move, and operator pages sometimes contradict their own FAQs. Check the current terms before you buy.