By destination

How to choose an eSIM for Vietnam & Thailand (SEA)

5 min read · Updated September 15, 2026

For a Southeast Asia eSIM, you can consider a single-country product if you're visiting just one country, or a Southeast Asia regional (multi-country) product if you're moving between several. Compare the total cost of both approaches for the same itinerary, and check the network the product supports and the official service area for the places you're visiting.

Single-country vs Southeast Asia regional product

For a trip to one country (e.g., Vietnam only), compare the total cost of that country's single-country product against a regional product. If you're moving between several countries — Thailand → Laos → Vietnam — you can use one Southeast Asia regional (multi-country) product that supports all the countries you visit. Note, though, that a regional product may attach to a different network in each country.

Main carriers by country (for reference)

Country	Main carriers
Vietnam	Viettel · VinaPhone · MobiFone
Thailand	AIS · TrueMove H · dtac (TrueMove H and dtac merged into True Corp in 2023; networks being integrated)
Indonesia	Telkomsel · Indosat · XL
Philippines	Globe · Smart · DITO

How much you'll need

Multiply your trip days by your expected daily use. For example, a 4–5 day trip where you expect about 500MB–1GB a day, mostly for maps, messaging, and social media, works out to roughly 3–5GB plus a little buffer (a sample calculation). Also check whether data is provided fresh when you move to a new country, or drawn down together across the whole itinerary.

What to check when choosing

Whether all the countries you visit are covered (for a regional product)
Whether the local network it connects to is stated
Whether tethering is allowed
When it activates (right after install vs on connecting locally)

FAQ

I'm going to both Thailand and Vietnam — do I need to buy separate products?

A single Southeast Asia regional product covering both countries can handle it. That said, if you're spending most of your time in one country, buying that country's single-country product is often cheaper.

How many GB is right for Southeast Asia?

Multiply your trip days by your expected daily use. If you expect about 500MB–1GB a day, mostly for maps, messaging, and social media, that's roughly 3–5GB for 4–5 days (a sample calculation). If you often use hotel Wi-Fi, you can go lower.

Is the signal good on islands and in remote areas?

A country being on the supported list alone doesn't guarantee a connection everywhere. Separately check whether the islands, accommodations, and routes you'll visit fall within the official service area of the network the product lists.

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