Thailand eSIM and SIM cards: the cheapest data anywhere, if you buy right

The cheapest data on this site

Nomad sells 50 GB of Thai data for $12 over 10 days. That is 24 cents a gigabyte — the cheapest mobile data of any country we cover, by a wide margin, and it is verified: read off Nomad's own site on 17 August 2026.

An earlier version of this page did not believe that price. It carried a warning that the 50 GB row looked too cheap to be true, and it cited a Nomad 20 GB plan costing more than the 50 GB as evidence that the ladder contradicted itself. Both of those were our errors, not Nomad's. We had the 50 GB plan recorded as running 30 days when it actually runs 10, which is what made the rate look impossible, and the 20 GB row does not exist: Nomad's Thai ladder goes 1, 3, 5, 10 and 50 GB, with no 20 GB tier at all. The plan is real, the price is real, and the doubt was ours.

What survives from that warning is the duration, and it is the thing to plan around. Fifty gigabytes in 10 days is a great deal if your trip is 10 days or less, or if you are happy to buy a second one. Over a month, Nomad's own 10 GB at $10 or Airalo's verified 50 GB at $27.50 are the plans that actually fit.

The dearest plan on the Thai board per gigabyte is Nomad's own 1 GB starter at $5.00 for seven days. Against the 24 cents at the top of its ladder, that is a 21-fold spread inside a single provider's price list, between two products doing the same job.

One row in that table is marked not on sale, and it is worth explaining. eSIM Go sells wholesale to resellers and publishes no consumer price at all — checked on esim-go.com on 18 August 2026, where there is no basket, no checkout and no per-country page, only a Contact Sales button. Its $17 for 10 GB is therefore not a price anyone can pay, and it can never be verified. We keep it visible because this site published it as buyable for months, and because the same $17 appears in our eSIM Go rows for eight other countries, which tells you how the old data was made. The full account is on our eSIM Go page.

Airalo's 20 GB at $18 is half again the price of Nomad's 50 GB at $12, for less than half the data — though Airalo gives you 30 days to use it and Nomad gives you 10. Note too how tightly Airalo and Saily track each other — a cent apart at 5 GB, a cent apart at 10 GB — and how closely Nomad joins them at 5 and 10 GB. Nomad's advantage in Thailand is not a general one; it is concentrated almost entirely in that top 50 GB tier.

Nobody roams into Thailand for free

Thailand is not in the EU and there is no equivalent arrangement covering visitors from anywhere else. Whatever your home operator charges for out-of-bundle roaming in Southeast Asia, you are paying it — and the standard advice applies: check the rate before you fly, because the number is usually large and it is usually per megabyte.

A handful of North American plans include limited international data at throttled speeds. If yours does, it is worth knowing whether Thailand is on the list, because throttled-but-included is a perfectly reasonable way to get through a week if all you need is maps and messaging. For everyone else, an eSIM installed before departure at 24 cents a gigabyte is one of the better deals in travel.

AIS versus True, and the thing we cannot tell you

Thailand has three networks that matter. AIS holds the largest geographic coverage in the country, at around 46% market share, and it is the strongest by a clear margin for islands, remote beaches, trekking routes and the northern highlands. True Corporation — formed from the DTAC and TrueMove merger in March 2023 — holds roughly 33% and is good in Bangkok and the major cities, but weaker once you leave them. National Telecom is the third.

Here is the honest problem: not one of the Thai plans in our data names its host network. Every row we hold comes with a blank where the carrier should be. So we can tell you with confidence that AIS is the network you want if your trip goes beyond the cities, and we cannot tell you which eSIM will give it to you.

That is an unsatisfying answer and we would rather give it than manufacture a better one. What it means practically: if your itinerary depends on coverage in genuinely remote places, check the provider's own FAQ or support chat for the host network before purchase, and treat silence as a warning. Providers that ride the strongest network tend to say so.

Where Thai coverage actually decides things

Bangkok is not a test of anything. Every network works, the average national speed is around 40 Mbps, and a $10 plan performs identically to a $27.50 one on the Skytrain.

The decisions get made elsewhere.

The islands and the boats between them. Phuket itself is fine. Phi Phi, the Similans, the longer ferry and speedboat crossings, the smaller Andaman and Gulf islands — that is where AIS's geographic advantage stops being a statistic. Coverage over water is a function of distance from a mast on shore, and the operator with more masts in more remote places wins.

The north. Chiang Mai is a well-connected city with a large remote-working population, which tells you the infrastructure there is solid. The highlands beyond it are a different proposition: valleys, ridgelines, the roads out to Pai and the border districts. Same logic, same conclusion.

Trekking and national parks. No network in any country holds up reliably in forested mountains. Download offline maps before you leave the road.

If your trip is Bangkok, Chiang Mai and Phuket town — which is a large share of first visits to Thailand — none of this applies to you and you should simply buy the cheapest gigabytes on the board.

The airport SIM, and the one thing it buys you

A Thai prepaid SIM at the airport runs about $10, and Thailand requires passport registration to activate one, so it is a staffed counter rather than a shelf. Suvarnabhumi, Don Mueang and Phuket all have them, and they are genuinely easy to use — Thailand's airport SIM market is mature in a way most countries' is not.

Against a Nomad plan at $12 for 50 GB, $10 for an unknown allowance is not obviously good value. But it buys you something no eSIM on our list currently offers: you can choose your network. Walk to the AIS counter and you get AIS. That is worth real money if you are heading for the islands or the north, precisely because the eSIM market will not tell you what you are getting.

It also solves the phone problem. If your handset does not support eSIM — check it against our eSIM-compatible phones list — the airport counter is the only route, and Thailand is a good country in which to need it.

The short version

Cities-only trip of ten days or less: Nomad's 50 GB at $12. It is the cheapest data on this site, it is verified, and it is far more than you will use. Network quality is not a variable in Bangkok or Chiang Mai.

Cities-only trip of two weeks or more: the 10-day window on that plan is the problem, not the price. Either buy it twice, or take Airalo's verified 50 GB over 30 days at $27.50. Buying a small tier is still a mistake in Thailand — every one of them costs more per gigabyte and the absolute saving is a few dollars at most.

Islands, trekking or the far north: still buy an eSIM before you fly so you land connected, but consider adding an AIS SIM at the airport for the remote leg. Ten dollars of insurance against having no signal on a boat is not an extravagance.

Anyone tempted by a 1 GB starter plan: don't. At $2.99 to $5.00 it is between twelve and twenty-one times the per-gigabyte rate of the best plan on the board, and Thailand will eat 1 GB in about two days of ordinary use with Grab, maps and messaging.

Our cheapest eSIM roundup puts Thailand's pricing next to the rest of the world — it is worth seeing quite how far out of line it is — and how we test explains the difference between the verified and indicative rows on the table above.