An eSIM works well in Thailand and costs less than most people expect: a 10 GB plan for 30 days is around $15 to $20, and a 1 GB week is about $4 to $5. Plans run on AIS or True. Buy before you fly, skip the airport SIM queue, and keep your home SIM active for calls and verification texts.
Thailand is one of the easiest countries for travel data. Tourist SIMs are cheap, coverage in cities is good, and the airport counters are efficient, which is exactly why the queue is long at midnight.
An eSIM removes that stop. You land with data already installed, order a car, and deal with the SIM question never. The trade-off is a data-only plan with no Thai number, which matters only if you need local calls or SMS.
Will your phone work?
The same hardware rule applies everywhere: an eSIM slot, and no carrier lock on that slot.
Phones bought under a US carrier contract are the most common problem. If Settings shows no EID, the phone cannot take an eSIM, whatever the marketing page says.
Which network you will be on
Two operators carry most travel eSIM traffic in Thailand. Both are good in Bangkok and the main tourist islands, with differences in the north and on smaller islands.
| Network | Type | What it means for you |
|---|---|---|
| AIS | National operator | The widest coverage overall. The safer pick for the north, national parks and smaller islands. |
| True | National operator | Strong in Bangkok, Phuket, Samui and other resort areas. Fast in cities. |
Bangkok, Chiang Mai, Phuket, Krabi and Koh Samui are well covered by both. On smaller islands, AIS is usually the more reliable of the two. Speeds are good enough for maps, calls and video, though beach areas can slow down in high season.
How much data you need
Thailand is not data-hungry by nature, but long bus and boat days add up. A normal two-week trip looks like this:
| What you do | Per day | 10-day trip |
|---|---|---|
| Maps and transport apps | 60 to 120 MB | 1 to 1.5 GB |
| Messaging and browsing | 100 to 200 MB | 1.5 to 2.5 GB |
| Photos and social uploads | 150 to 350 MB | 2 to 4 GB |
| Video calls | 200 to 500 MB | 2 to 5 GB |
| Streaming | 300 MB to 1 GB | 3 to 10 GB |
For a two-week trip with normal use, 10 GB is plenty. A one-week beach trip fits in 3 to 5 GB. Unlimited plans are cheap in Thailand, but many slow down after a daily cap, so read the small print.
What plans cost
Thai plans are short and cheap. These are the shapes worth comparing:
Enough for a short stopover or a light week.
The comfortable default for two weeks.
Convenient, but check the daily throttle threshold.
A local tourist SIM at the airport is often cheaper per gigabyte than an eSIM, at around 300 to 600 baht for a week or two. The eSIM buys you time and no queue, not the lowest price.
Buy, install, activate
Install on wifi before you leave. Thai airports have wifi, but it usually wants a code from a local number, which is the wrong moment to need one.
- Before you buyConfirm the phone has an EID under Settings and is not carrier-locked.
- T-3 daysBuy the plan and save the QR code and activation details offline.
- T-1 day, on wifiInstall the eSIM and label it Thailand. Leave it off as the primary line.
- On landingSet the Thai eSIM as mobile data, enable data roaming for it, keep your home SIM for calls.
- First 5 minutesOpen a map. If nothing loads, toggle airplane mode and check the data line again.
What the plan does not include
- A Thai phone number, so no local SMS or calls from a Thai number.
- Unlimited hotspot. Tethering rules vary by plan and provider.
- Coverage on remote islands and in national parks. AIS is the better bet there.
- Speed guarantees in beach areas during high season.
eSIM, local SIM or roaming?
The three options, priced for a two-week trip:
| Option | Cost for a 10-day trip | Setup | Phone number | Best for |
|---|---|---|---|---|
| Travel eSIM | $15 to $20 for 10 GB | 10 minutes before the flight | No | Most travellers who want to skip the airport queue |
| Local tourist SIM | $10 to $18 for a week or two | Airport or 7-Eleven, passport needed | Yes, a Thai number | Long stays, local calls, the cheapest data |
| Roaming with your home plan | $8 to $15 per day | None | Your own number | Short stopovers only |
When it does not work
No service at the airport. Data roaming is usually off for the new line. Turn it on, set the eSIM as the data line, and restart.
Slow data on an island. Switch to AIS manually, or move to a higher floor or the beach edge. Congestion is seasonal.
Unlimited plan slows down after a few hours. You hit the daily throttle cap. Check the plan details, or buy a top-up with a fixed data amount.
Bank or airline SMS does not arrive. The eSIM has no number. Keep your home SIM active for SMS, and check roaming charges with your carrier.
Before you fly
Frequently asked questions
Does an eSIM work in Thailand?
Yes. Travel eSIMs run on AIS or True, and coverage in Bangkok, Chiang Mai, Phuket, Krabi and Samui is good. You need an unlocked, eSIM-compatible phone.
Is an eSIM cheaper than a Thai tourist SIM?
Usually not per gigabyte. A local tourist SIM can be cheaper, especially for long stays. The eSIM saves the airport queue and the passport registration, which is worth more to some travellers than the price difference.
Can I get a Thai phone number on an eSIM?
Not on a travel eSIM. Those are data-only. If you need a Thai number, buy a local tourist SIM at the airport or a 7-Eleven.
How much data do I need for two weeks in Thailand?
10 GB covers maps, messaging, photos and some video. A beach week fits in 3 to 5 GB.
Does the eSIM work on the islands?
On the main islands yes, with AIS the safer choice on smaller ones. Expect slower speeds in beach areas during high season.