Best eSIM in Thailand: how to buy, activate and top up

Once you are in the country, official prepaid options can usually be topped up through apps, websites, shops, or convenience stores.

Landing in Bangkok without data is a headache when you need Grab, maps, hotel messages, or a one-time passcode. The good news is that Thailand makes eSIM setup easy, whether you buy before you arrive, or choose a tourist plan after you land.

You’ll generally choose between an official Thai network, which is easier for local calls and top-ups, or a reseller eSIM, which is easier to buy before travel.

This guide helps you compare AIS, True and dtac options. It also details how to set up your phone, manage top-ups, and pay eligible providers in THB with Wise card where card payments are accepted.

Wise eSIM

Eligible Wise personal and business customers in Singapore can buy a Wise eSIM that covers 150+ countries and regions. To see destinations and plans, open the Wise app.

• Plan: Depends on your route, destinations, stay length and data needs.
• Activation: Data starts when your eSIM connects to a local network, not at installation.
• Device: Must support eSIM and be carrier-unlocked.
• Payment: Wise balance only. No external cards or bank accounts.

Get Wise eSIM

Key takeaways

• Buy before arrival, install on Wi-Fi, and switch on the eSIM when you land.
• AIS is often the safer pick for wider country coverage, while True and dtac are easy to find in cities and airports.
• Passport registration is usually required for local tourist plans, so check with the provider before you pay.
• Official top-ups are simplest through myAIS, provider sites, shops, or 7-Eleven for eligible lines.
• Where cards are accepted, you can pay in THB with Wise card and review any provider, merchant, or conversion fees at checkout.

Can you buy a Thailand eSIM before you arrive?

Yes. In most cases, you can buy a Thailand eSIM online before arrival, either from an official local operator such as AIS or True, or from a travel eSIM store. This is the fastest route if you want data working as soon as you land.

If you want a local number and easy top-ups, official Thai operator plans are usually better. Reseller eSIMs are often easier to buy before travel, but many are data-only or manage top-ups inside their own app. If you are still weighing getting an eSIM against airport counters, our Thailand SIM guide covers this.

Insider’s Tip: Many of the so-called ‘Unlimited’ local SIMs you buy at the airport can block or severely throttle personal hotspots for laptops. If you plan on working remotely, check the details carefully before purchasing.

What to check before you buy

Most failed activations come back to the handset, not the package. Your phone must support eSIM and it must be carrier-unlocked, otherwise the plan may not work as expected.

Check this before you pay, especially if you want Grab, LINE, maps, and OTP texts working as soon as you arrive. If you plan on an extended stay in Thailand, mobile setup is one of several jobs to sort out in your first week in Thailand.

• Open your phone settings and look for Add eSIM, Add Cellular Plan, or SIM Manager.
• Confirm the phone is unlocked.
• Decide whether to keep your home SIM active for calls, banking codes, or WhatsApp.
• Check whether you need a Thai number for calls, deliveries, or sign-ups.
• Verify hotspot rules and compatibility on the provider page or Apple Support.

Compare the main eSIM options in Thailand

Official Thai operator eSIMs usually mean a Thai number, clearer topup routes, and better control if staying longer than a week. International stores are more plug-and-play, but the rules depend on the reseller.

AIS suits wider routes better than city-only stays. True and dtac, now under the same broader group, are highly visible at airports and in tourist areas. Island and rural performance can still vary by location and weather.

For everyday arrivals, the top must-have apps in Thailand show why data use can feel bigger than you planned.

AIS tourist eSIM

For wider routes beyond the main cities, AIS is often the first network travellers check. On its official tourist plan page, AIS listed examples from ฿699 for 15 days to ฿1,599 for 60 days on 3rd September 2026. Check the latest validity, local call credit, and your top-up route before you buy.

True and dtac tourist eSIM

True and dtac offers are highly visible at airports and online, which suits travellers who want to get connected fast. The shared tourist page shows 8, 15 and 30 day Infinite SIM options, plus a 10-day data-only format.

The page notes that passport registration is required for tourist SIMs. Verify whether the offer is the True or dtac version, how call credit works, and whether you will top up on the app, online or in a shopsuch as 7-Eleven.

International eSIM stores

International stores such as Airalo, Holafly, MobiMatter, Sim Local are handy if you want to buy before flying and avoid queues at the airport. The catch is that some plans are data-only, some slow down after fair use, and top-ups may work only inside the seller’s app.

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How to install and activate your eSIM

Install the eSIM at home on strong Wi-Fi, leave it off for mobile data, then switch it on after landing.

If the signal is weak, check that the eSIM is switched on, the right plan is set for data, and roaming is enabled when prompted. If the QR code fails, some providers limit reuse. A reboot and a fresh Wi-Fi connection often fix the first attempt.

How to top up or extend your Thai data plan

When the first package runs out, you can top up credit, buy an add-on data pack, or replace the plan. Official Thai prepaid plans are easier because the number stays in the local system, while many reseller plans ask you to buy more data in their app.

AIS gives a clear example. On its tourist page, the myAIS flow is log in, tap Top Up, and follow the steps. AIS also lists online top-up, shops, and add-on data packs. True’s tourist FAQ points travellers to True Shop, 7-Eleven, and other selected top-up points, which is handy if you prefer cash.

Writer

Steve

Insider tip

Airport counters are great for getting connected fast, but managing add-ons in the provider app is usually easier once you know your number.

For longer stays, local payment habits matter more. Once you have a Thai account, many residents manage bills through apps from Bangkok Bank, Kasikornbank, or Krungthai Bank. Our guides to opening a bank account in Thailand and mobile banking in Thailand explain that next stage.

How to pay your local phone bill in Thai Baht

This matters most when you buy online before arrival, top up in an app, or pay a reseller that bills in baht. 

Where card payments are accepted, you can pay in THB with a Wise card, or a Wise digital card if that feature is available to you. If you do not already hold THB, Wise can auto-convert at the mid-market rate with a conversion fee.

Wise does not add a foreign transaction markup, but provider charges, reseller markups, merchant fees, and card availability rules can still apply. It should be noted that Wise will only work when that checkout accepts international cards.

If a checkout offers to switch the price into pounds or euros, decline that option and pay in THB instead. That helps you avoid dynamic currency conversion. If you want a card for Thai mobile top-ups and other baht spending, compare the Wise travel money card for Thailand and check country availability before relying on it.

When a physical SIM or local prepaid plan may be better

An eSIM is not the right answer for everyone. A physical SIM can be better if your phone is locked, does not support eSIM, or you want a simple cash top-up route. It is also easier if you prefer in-person help at an airport counter, mall kiosk, or provider shop.

For a longer stay, a standard local prepaid plan can feel more practical than a tourist package. You may want support that fits home internet, local banking, and recurring bills. In that case, our guide to setting up internet, TV, and home phone in Thailand helps you think beyond your arrival SIM.

Writer

Steve

Insider tip

There is an AIS shop just after immigration at Suvarnabhumi Airport where you can purchase a SIM. If the shop accepts Visa/Mastercard you can pay with your Wise card. There is also a 24-hour kiosk by the baggage reclaim area in case you have a late arrival.