Thailand SIM Card and Internet Guide — Stay Connected from Landing
Getting online in Thailand is easy and cheap — a tourist SIM card costs less than a airport coffee and gives you fast 4G/5G across most of the country. Here's the quick guide.
At the Airport
All three major Thai carriers have booths in the arrivals hall at Suvarnabhumi and Don Mueang airports. They're open 24/7 and the process takes 5 minutes.
The Three Carriers
AIS — Best overall coverage, especially on islands and in rural areas. The premium choice.
DTAC (now merged with TRUE as TRUE-DTAC) — Good urban coverage, competitive tourist packages. Sometimes slightly cheaper.
TRUE — Largest 5G network in Bangkok. Merged with DTAC.
Tourist SIM Packages (Typical 2026 Pricing)
| Duration | Data | Price (THB) |
|---|---|---|
| 8 days | 15 GB | 299 |
| 15 days | 30 GB | 499 |
| 30 days | 50 GB (AIS) | 599 |
| 30 days | Unlimited (throttled after cap) | 799 |
All tourist SIMs include some calling credit. Passport required for activation (regulation).
Which Provider Should You Choose?
AIS if: You're visiting islands (Koh Lipe, Koh Mak, Koh Jum), national parks, or rural areas. AIS consistently has the widest coverage outside cities.
TRUE-DTAC if: You're staying mainly in cities and tourist areas. Coverage is comparable to AIS in popular destinations.
For most tourists: AIS 30-day, 50 GB SIM (599 THB) is the safest bet. You'll rarely run out of data or coverage.
Buying After the Airport
If you skip the airport booths, SIM cards are available at: - 7-Eleven — Every 7-Eleven in Thailand sells top-up SIMs and data packages. Staff can help activate. - Carrier shops — In every shopping mall and most towns. - Phone shops — Independent shops near tourist areas.
Connectivity by Location
| Location | 4G/5G Coverage | WiFi Availability |
|---|---|---|
| Bangkok | Excellent (5G available) | Widespread |
| Chiang Mai | Excellent | Widespread |
| Phuket | Excellent | Widespread |
| Koh Samui | Good | Most hotels/cafes |
| Koh Tao | Good | Variable |
| Koh Lipe | Moderate (AIS best) | Limited |
| Koh Mak/Koh Kood | Moderate | Hotel only |
| National Parks | Variable | Usually none |
eSIM Alternative
If your phone supports eSIM, you can buy a Thai eSIM online before arrival: - Airalo — Thai data eSIMs from $5 USD for 1 GB / 7 days - Holafly — Unlimited data eSIMs from $19 USD for 5 days - AIS eSIM — Available through the AIS app
Advantages: No physical SIM swap, keep your home number active. Disadvantage: No local Thai phone number for calling.
Tips
- Bring an unlocked phone — If your phone is carrier-locked, a Thai SIM won't work. Most modern phones are unlocked.
- Download offline maps — Google Maps and Maps.me work offline. Essential for motorbike exploring on islands with spotty signal.
- WiFi calling — If your home carrier supports it, keep WiFi calling enabled for free calls home over hotel WiFi.
- Charge before islands — Remote islands can have limited electricity. Charge your phone and power bank before heading to less-developed destinations.
FAQ
Do I need a Thai SIM card or can I use roaming?
A Thai SIM card is dramatically cheaper. International roaming from most Western carriers costs $5-15 USD per day. A Thai SIM gives you 30 days of fast data for $17 USD. Unless your carrier offers included roaming (like some unlimited plans), buy a Thai SIM.
How fast is mobile internet in Thailand?
In cities: 20-100 Mbps on 4G, up to 500 Mbps on 5G. More than enough for video calls, streaming, and remote work. On islands: 5-30 Mbps typically. National parks and remote areas: 1-10 Mbps or no signal.
Can I keep my Thai SIM after leaving Thailand?
Yes — tourist SIMs remain active for 30-90 days after the last top-up. If you're returning to Thailand, you can reactivate by adding credit within the validity period. AIS and TRUE-DTAC apps allow top-up from overseas.