Getting a Thai SIM card is one of the first things you should do on arrival. It takes 5 minutes at any network counter, costs a few hundred baht, and gives you a reliable local number and data connection immediately. The only decision is which network and which plan.
The Three Main Networks Compared
AIS
Best for: Nationwide coverage, rural travel, most consistent speeds. Slightly more expensive than competitors. Widest roaming agreements. Recommended for those travelling outside major cities frequently.
TrueMove H
Best for: City users and those wanting competitive pricing. True and DTAC merged in 2023, creating the second-largest network. Strong in Bangkok and major tourist areas. Good unlimited data plans.
DTAC (now True)
Best for: Budget-conscious users. DTAC brand continues alongside TrueMove H on the merged network. Popular prepaid plans at very competitive prices. Good urban coverage.
Tourist SIM vs Long-Stay Monthly Plan
| Tourist SIM | Long-stay monthly plan | |
|---|---|---|
| Best for | Stays up to 30 days | Stays of 1 month or more |
| Typical cost | 299–599 THB for 7–30 days | 299–599 THB/month |
| Data | Unlimited (throttled after limit) or high-volume | Unlimited (throttled after 30–60GB) |
| Calls | Limited or unlimited to Thai numbers | Unlimited to Thai numbers included |
| Number | New Thai number assigned | Keep the same number month-to-month |
| Setup | Instant at point of purchase | Requires more documentation sometimes |
For long-term expats, a monthly postpaid or prepaid plan is better value than a tourist SIM. The cost is similar per month but you keep the same number, which matters once you start using it for banking, delivery apps, and other services that link to your mobile number.
Where to Buy: Airport vs City vs Online
Airport (Suvarnabhumi / Don Mueang): All three networks have staffed counters in the arrivals hall. The selection covers tourist packages and basic monthly plans. Prices are the same as in-city there is no airport premium. Buying here is convenient and saves you being without data on your first day. Staff speak English.
Network stores in city: The widest plan selection, including postpaid contracts and higher-end monthly plans. Most major shopping malls have all three network stores (Central World, Siam Paragon, Central Festival). Staff in main branches speak English.
7-Eleven and FamilyMart: Stock tourist SIMs and top-up cards for prepaid plans. More convenient than a network store for a basic tourist package but the staff cannot assist with account setup or plan questions.
Online (before departure): International eSIM providers like Airalo and Holafly sell Thailand data eSIMs that can be activated on your phone before you board. Useful for data on arrival. Not a substitute for a local Thai number if you need one for banking or registrations.
eSIM Options for Thailand
eSIM is supported by all three Thai networks and by most modern smartphones (iPhone XS and later, most Android flagships from 2019+). Options:
- AIS eSIM: Activated at an AIS store or via the AIS app. Good coverage, available as tourist and monthly plans.
- TrueMove H eSIM: Activated via the True Move H app or in-store. Competitive monthly plans.
- International eSIM providers (Airalo, Holafly, Ubigi): Data-only plans that can be set up entirely before you leave home. Useful for data on arrival, but these do not give you a Thai phone number you get data only.
Documents Required to Buy a Thai SIM
Thailand requires passport registration for all SIM card purchases. Without a passport, you cannot buy a SIM not even from a 7-Eleven. Bring your actual passport, not just a copy. The staff scan it or enter the passport number into the registration system at the point of purchase. The SIM is activated to your passport number.
For postpaid monthly plans, some networks additionally require proof of Thai address (TM30 receipt or rental contract). Tourist SIMs and prepaid plans require only a passport.
Plans and Costs (2026)
| Plan type | Network | Indicative cost | Data |
|---|---|---|---|
| Tourist 7-day | AIS/True/DTAC | 299 THB | Unlimited (throttled after 1.5GB/day) |
| Tourist 30-day | AIS/True/DTAC | 499–599 THB | Unlimited (throttled after 30GB) |
| Monthly prepaid unlimited | AIS | 499–599 THB/month | Unlimited, throttled after 50–60GB |
| Monthly prepaid unlimited | True/DTAC | 299–499 THB/month | Unlimited, throttled after 30–60GB |
| International eSIM (data only) | Airalo/Holafly | USD 10–25/month | Varies by plan |
Prices are indicative and change regularly. Check network websites directly for current plans.
How to Top Up Your Thai SIM
Prepaid SIMs are topped up by purchasing a top-up voucher at 7-Eleven or FamilyMart (scratch-card style vouchers are available in 50, 100, 200, 300, and 500 THB denominations), or directly through the network's app (AIS app, True Move H app) using a credit or debit card. Auto-renewal for monthly plans is set up through the app.