Chiang Mai: quick in town, thinner once you head uphill

The city itself is easy

Signal in Chiang Mai is excellent across the city centre, the Old City, Nimmanhaemin — the Nimman Road area that serves as the remote-work hub — and every main tourist district. The city routinely tops global digital-nomad rankings, and the network investment has followed the population.

Coworking spaces here run on fast fibre, which matters, because it changes what mobile data is actually for. In Chiang Mai it is the fallback, the commute companion and the layer that ties the day together, rather than the thing your income depends on. That should push your plan size down, not up.

Where it stops

Gaps appear in the mountains north of the city. Doi Inthanon National Park, which contains Thailand's highest peak, the remote trekking routes, and the northern border highlands all have weaker coverage. Of the Thai networks, AIS extends furthest into that terrain.

Here is the awkward part, and it is worth being blunt about it: you cannot buy your way onto AIS through a travel eSIM, because none of the providers we track publish a host network for Thailand. Saily, Airalo, eSIM Go, Nomad and eSIMCard all leave it unstated. Airalo sells its Thai plan under the name Maew, which is a product label, not a carrier.

So if your trip is genuinely built around Doi Inthanon or multi-day treks in the border highlands, the only way to actually choose a network is a local prepaid SIM bought in a carrier shop, where you know what you are getting. For everyone whose Chiang Mai is the Old City, Nimman and a day trip or two, this does not arise.

Either way, download offline maps for the mountain days. That advice does not depend on which network you end up on.

The long-stay arithmetic

This is where Chiang Mai differs from every other Thai page. A tourist buys for a week; a lot of people here buy for a month.

These Thai prices were read from the providers' own sites on 13 August 2026:

Check the top of the ladder before you assume the small plan is the thrifty one. Airalo's 50 GB over 30 days at $27.50 is $0.55 a gigabyte, well under a fifth of the per-gigabyte cost of the 1 GB starter. For a month-long stay where fibre does the heavy lifting and mobile fills the gaps, 20 GB at $18.00 is usually enough and 50 GB is the safety margin. Airalo also lists unlimited over 30 days at $49.00, verified, which is the option for anyone who would rather not think about it at all.

Nomad's listings are cheaper again, and they are verified: 10 GB over 30 days at $10, and 50 GB at $12 — 24 cents a gigabyte, the lowest rate on this site. An earlier version of this page called both figures unverified leads rather than quotes; that was our own record being wrong, not the prices. The one caveat that matters in Chiang Mai is the window on the big plan: those 50 GB run for 10 days, not 30, so for a month here the plans that fit are Nomad's 10 GB at $10, Nomad's unlimited month at $33 or Airalo's verified 50 GB over 30 days at $27.50.

A Thai local SIM is about $10 at the airport in our data, from AIS, True Corporation or National Telecom, with a passport needed to register. For a month here that is the cheaper route, it gets you a Thai number, and it is the only way to pick your network deliberately. For a four to seven-day visit, 3 to 5 GB on an eSIM covers maps, messaging and temple navigation without a shop queue.

Country-wide pricing and coverage sit on the Thailand hub.