If you are working remotely in Thailand and want one answer: for a stay of two weeks or more, buy an AIS Tourist SIM — it has the most reliable coverage on the islands and the quiet edges of the country where you will inevitably end up taking a call. For the first 24 hours, before you have found a counter or dealt with passport registration, land with a [Saily](https://saily.com) eSIM already active so your phone works the moment you clear immigration. That combination — eSIM for arrival, AIS for the long stay — is what most nomads actually want, and it costs less than overthinking it.
The rest of this guide explains why, with real 2026 prices, where to buy, and the registration reality nobody warns you about.
The players: it is really only two companies now
Thailand markets three tourist SIM brands, but since the 2023 merger there are only two networks behind them. True Corporation now owns both TrueMove H and dtac — they still sell separate tourist SIMs, but the towers are increasingly shared. AIS is the independent third pillar and, for a remote worker, usually the smart pick.
- AIS — best rural and island coverage, strongest signal on ferries and the far sides of Koh Samui, Koh Phangan, and Koh Tao. This is the network to have if you will leave Bangkok.
- TrueMove H — the biggest operator by subscribers (~51% share, 99% population coverage), excellent in Bangkok, Chiang Mai, and dense tourist zones. Fast urban 5G.
- dtac — the same True network underneath, but its Happy Tourist SIM is genuinely the cheapest short-trip option. Worth it only if you are here a week or less.
For work that depends on a stable connection wherever you happen to be, AIS wins on consistency. In a Bangkok condo, all three are excellent and it barely matters.
Comparison table (2026)
Prices are approximate; USD assumes ~36 THB to the dollar. Local tourist plans are unlimited data with a daily high-speed cap before soft throttling.
| Option | Price | Data | Coverage | Where to buy |
|---|---|---|---|---|
| AIS Tourist SIM | 499 THB / 8 days; 1,199 THB / 30 days (~$14 / $33) | Unlimited, ~2–3 GB/day full speed | Best islands + rural | Airport counters, AIS shops, 7-Eleven |
| TrueMove H Tourist SIM | 499 THB / 8 days; 1,199 THB / 30 days (~$14 / $33) | Unlimited 5G | Best in cities | Airport counters, True shops, 7-Eleven |
| dtac Happy Tourist | 299 THB / 8 days (~$8); 599 THB / 15 days | 15 GB / 30 GB high-speed | Same as True | Airport counters, 7-Eleven |
| Saily eSIM | $5.99 / 3 GB; ~$11 / 10 GB; unlimited from ~$19 | Runs on AIS or TrueMove H | Nationwide | App, before you fly |
| Airalo eSIM | ~$6 / 3 GB; ~$16 / 10 GB | Runs on local networks | Nationwide | App, before you fly |
Arrival: have data before you land
The single best connectivity decision you can make is to install a travel eSIM before your flight and switch it on as the plane taxis in. You walk off jet-lagged, and your maps, ride-hailing app, hotel confirmation, and messages all just work — no hunting for a counter, no queue, no passport photocopy while you are running on three hours of sleep.
A Saily eSIM is the cleanest way to do this. It installs from the app in a couple of minutes, runs on AIS or TrueMove H, and a small plan is cheap enough to treat as disposable: a 3 GB / 30-day plan is around $5.99, and a 10 GB plan runs about $11. For a nomad, the right move is a modest Saily data plan to bridge your first day or two, then buy a local AIS SIM once you are settled and rested. Airalo is a fine alternative if you already use it, at broadly similar prices. Either way, the point is the same: arrive connected.
This matters more in Thailand than in most countries because of registration friction (below) — the last thing you want after a red-eye is to discover the 7-Eleven clerk cannot activate your SIM without a manager.
The long stay: why AIS is the local SIM to buy
If you are here for a month of remote work, a local physical SIM is still the better economic and practical choice than eSIM-only. An AIS 30-day Tourist SIM is 1,199 THB (~$33) for effectively unlimited data with a generous daily full-speed allowance — cheaper per gigabyte than most unlimited travel eSIMs, and it comes with a Thai number, which is genuinely useful for food delivery, Grab, and booking confirmations that expect an SMS.
Buy AIS specifically if your Thailand includes islands, national parks, dive trips, or beach towns. That is where the network gap shows up: on a longtail boat between Koh Tao and Koh Phangan, or on the western side of Koh Lanta, AIS holds a signal when the others fade. If you will genuinely never leave Bangkok or Chiang Mai, TrueMove H is equally good and sometimes faster on urban 5G — but AIS is the safer default because you rarely know in advance where a good spot to work will turn out to be.
Skip dtac for a long stay. It rides the same True network, so you gain nothing over TrueMove H, and its long-duration pricing is less compelling than its cheap short plan.
Where to actually buy
Airport counters are the easy path. AIS, TrueMove H, and dtac all staff booths in the arrival halls at the major international gateways:
- Suvarnabhumi (BKK) — arrival halls near baggage claim, open late for evening flights
- Don Mueang (DMK) — arrival floor between the two terminals
- Phuket (HKT), Chiang Mai (CNX), Koh Samui (USM), Chiang Rai (CEI) — all have counters in arrivals
Airport prices are the same tourist-plan prices you would pay elsewhere, and staff handle registration on the spot — this is the low-stress option and the counters are competent.
Carrier shops in malls (AIS, True 5G stores near BTS/MRT stations) give you the widest plan selection and English-speaking staff. 7-Eleven, FamilyMart, and Big C sell SIMs too and are everywhere, but activation can be hit-or-miss depending on the clerk, so they are best for topping up rather than first activation.
The registration reality
Thailand requires every SIM — tourist SIMs included — to be registered to a passport under NBTC rules. In practice that means: bring your physical passport, and expect your photo to be taken at the point of sale. It takes a few minutes at an airport or carrier shop; at a convenience store it can be slower or occasionally refused if the staff are not set up for it. You can register a handful of SIMs per passport, so there is no issue getting one, but there is no anonymous, walk-up-and-go option. This is exactly why arriving on an eSIM you activated at home removes the one genuine pain point of getting online here.
eSIM vs local SIM: the honest verdict
- Short trip (under ~10 days) or you value zero hassle: go eSIM. A Saily plan covers a week comfortably, installs before you fly, and you never touch a passport-registration counter. For a quick city visit this is the better experience, full stop.
- A month or more of remote work: buy an AIS Tourist SIM once you land. Unlimited-style data for ~$33/30 days is hard to beat, and the Thai number is a real convenience. Use a small Saily plan only to bridge day one.
- Heavy uploader / video-call all day: a local unlimited SIM (AIS or TrueMove H) is more forgiving than an eSIM's fair-use cap. Most travel eSIMs, Saily included, throttle after a daily allowance; local unlimited plans are more generous in practice.
The trap to avoid is treating this as either/or. The nomads who never have a connectivity problem in Thailand do both: they land on a [Saily](https://saily.com) eSIM, then pick up an AIS SIM for the long haul. Total cost is well under $50 for a month online, and you are never once stuck offline in an airport queue.
One last note for 2026: local eSIM is fully supported by AIS and True if you would rather skip physical SIMs entirely — you can buy an AIS eSIM in-country and register it the same way. But for most people the physical AIS SIM remains the cheapest, simplest long-stay option, with a travel eSIM handling the part that actually matters: being connected the second you arrive.