SIM Card and eSIM in Chiang Mai: AIS and True Compared
Buy an AIS tourist SIM at the airport, or an AIS or True shop at Central Festival, with your passport. The 8-day plan costs 499 Baht at AIS and 499 THB at True. Tourist SIM validity stops at 60 days. After that AIS reconfirms identity by SMS to 4444161, and True re-identifies you with a passport at a shop.
The terminal hall at Chiang Mai International Airport.
Tourist SIM prices at AIS and True
You land with a flat phone, and the AIS 8-day plan card says 499 Baht. Have your passport in your hand before you reach the counter. True registers every SIM with a valid passport.
Prices below are as listed on each operator’s own page. True prices include VAT.
The AIS 30-day plan gives unlimited data at max speed on 5G or 4G. AIS cards also include free calls within the AIS network and a 100 Baht bonus for calls to all networks in Thailand and international calls via 00300.
The True 8-day plan includes unlimited 5G internet at max speed, unlimited Wi-Fi and unlimited calls to all networks in Thailand. The same card adds 100 THB of calling credit for international calls. For 349 THB you get unlimited 5G internet and unlimited Wi-Fi on the True 10-day plan.
Which length to pick
Match the plan to your stay. The 30-day plan costs 1,199 Baht at AIS and 1,199 THB at True. True also sells a 10-day plan at 349 THB.
For a long weekend, the AIS 5-day plan costs 399 Baht. For two weeks, the 15-day plans cost 699 Baht at AIS and 699 THB at True.
A 60-day AIS plan costs 1,599 Baht. Tourist SIM validity stops at 60 days on True and dtac.
Buy a SIM at Chiang Mai International Airport
Buy an AIS tourist SIM on the 1st floor at Exit 2, Exit 6, Exit 11 or at Baggage Claim No. 5.
True and dtac sell at service centres nationwide and at airport locations, 24/7. Ask at the counter if you want True.
The arrivals baggage hall, where an AIS tourist SIM point sits at baggage claim.Chiang Mai International Airport 60 ถนน มหิดล Suthep, Mueang Chiang Mai District, Chiang Mai 50200, Thailand · Open in Google Maps (opens in a new tab)
AIS sells tourist SIMs at all AIS Shops and all Telewiz Shops nationwide. The Central Festival shop is at 99/3 Lampang - Chiang Mai Superhighway, Fa Ham, Mueang Chiang Mai District, Chiang Mai 50000.
Opening hours are 11 AM-7 PM Monday to Thursday, 11 AM-8 PM Friday and Saturday, and 10 AM-7 PM Sunday. The AIS Call Center is 1175.
The AIS shop at Central Festival.Inside the AIS shop, where tourist SIMs are sold over the counter.AIS 99/3 Lampang - Chiang Mai Superhighway, Fa Ham, Mueang Chiang Mai District, Chiang Mai 50000, Thailand · Open in Google Maps (opens in a new tab)
The True and dtac terms require the SIM to be registered with a valid passport, with a maximum of 3 SIMs per person per brand. AIS asks tourists to register the SIM before use in Thailand.
Take your passport, the SIM card and your phone to the counter.
If you register yourself, SMS the passport number to 4444161 and follow the instructions in the reply.
Keep the SIM for use soon after registration. A number registered in an individual’s name must be activated within 60 days of registration.
If registration is incomplete, you get warnings by SMS, MMS and a voice notification on outgoing calls, and service may be interrupted.
You can buy a local eSIM on the AIS network online and use it immediately. A new eSIM is available at any AIS shop, or through the AIS online store where you activate it on the phone yourself. The AIS eSIM service has no service fee.
Load the AIS eSIM one of two ways: a QR code or the myAIS app. Scan the whole QR code, or the cellular plan will not be added.
True sorts its Infinite packages into an eSIM tab and a SIM Card tab. True and dtac also sell through the True/dtac Online Store. True limits the service to devices supporting 5G, 4G or 3G on its designated frequencies.
Top up an AIS SIM through the myAIS app, online top-up, an AIS shop or WeChat Pay. For True, go to a True Shop, 7-Eleven or another selected top-up point, tell the staff the amount and give your phone number. Press *123# on a True SIM to check balance and validity.
Tourist SIM validity cannot be extended by top-up after expiry on True and dtac.
Staying longer than 60 days
You have three routes, and the first two are sourced.
Keep the tourist SIM. A tourist keeping an AIS tourist SIM beyond 60 days from activation must reconfirm identity. Send the passport number by SMS to 4444161, free of charge, and finish verification through the link in the reply. Or visit an AIS Shop.
On True and dtac, top-up cannot extend an expired tourist SIM. To continue, re-identify with a passport at any True dtac Shop or call 1242 for True or 1678 for dtac.
Move to a regular prepaid number. AIS NET SIM plans start at 299 baht per month for 1 GB, 499 baht for 3 GB and 1099 baht for 14 GB. A True prepaid or postpaid SIM registers through its app, ending with identity verification.
AIS runs its eSIM convert and transfer service for all individual prepaid and postpaid customers. Foreign customers give the passport number registered with AIS.
Both operators word the tourist product for tourists. It is not stated whether a long-stay visa holder can keep reconfirming, or what a postpaid contract requires. Ask AIS on 1175 or True on 1242 with your visa type before day 60.
1Pick the lengthAIS sells 5, 8, 15, 30 and 60 days. True sells 8, 10, 15 and 30 days.
2Bring your passportThe SIM must be registered with a valid passport under NBTC regulations.
3Buy at the airport or a shopAIS has points at Chiang Mai Airport on the 1st floor. Both operators have shops at Central Festival.
4Finish registrationOn AIS, foreign nationals SMS the passport number to 4444161 and follow the reply.
5Watch the 60-day limitTourist SIM validity must not exceed 60 days on True and dtac; AIS asks for reconfirmation beyond 60 days. Plan the next step before day 60.
Not confirmed: Postpaid: AIS and True publish no document list for foreigners, so ask AIS on 1175 or True on 1242 with your visa type. Tourist terms: both operators word the tourist product for tourists. True at the airport: airport locations are mentioned but not listed.
True and dtac register the SIM with a valid passport under NBTC rules, with a maximum of 3 SIMs per person per brand. AIS asks you to prepare a Thai ID card or passport, the SIM card and the phone.
Which AIS tourist SIM is cheapest for one week?
The AIS 8-day plan costs 499 Baht and the 5-day plan 399 Baht. A 1-day plan costs 49 Baht for 1 GB of data.
How long can a tourist SIM stay active?
True and dtac say validity must not exceed 60 days. On AIS, a tourist who wants to continue beyond 60 days from activation must reconfirm identity.
Can I buy an eSIM before I land in Thailand?
Yes. A visitor can buy a local AIS eSIM online and use it immediately. True sells its Infinite packages under an eSIM tab.
Where do I top up an AIS tourist SIM?
Top up through the myAIS app, online top-up, an AIS shop or WeChat Pay.
Where do I top up a True SIM?
Go to a True Shop, 7-Eleven or another selected top-up point and tell the staff the amount and your phone number. Dial *123# to check balance and validity.
Does the True tourist SIM work on iPhone and Android?
It works with every phone model. The service is limited to devices supporting 5G, 4G or 3G on True's designated frequencies. Ask the counter to test the SIM in your phone before you leave.
What can I do after 60 days on a tourist SIM?
On AIS, reconfirm identity by SMS to 4444161 or at an AIS shop. On True and dtac, re-identify with a passport at a True dtac shop. AIS also sells regular prepaid plans such as a 299 baht NET SIM with 1 GB.
Who do I call if the SIM stops working?
The AIS Call Center is 1175. True is 1242 and dtac is 1678.
General information checked against the sources listed above, not legal advice for your situation. Rules and office practice change; confirm with the immigration office or a licensed adviser before you act. See how guides are checked.
