Best eSIM for Thailand

For most travelers, a travel eSIM running on AIS or True, and Airalo is the best overall pick, with Thailand plans from $4 and 5GB for 30 days at $8. Saily is the cheapest, from $2.99. For unlimited data, Nomad charges $15 for 10 days and Saily or Airalo about $49 for a month. If you're a heavy data user or need a Thai number, compare those against the ฿499–699 unlimited tourist SIMs at the airport before you decide.

The eSIM wins on convenience. No lines, no passport registration, and your home SIM stays in for bank codes. A physical tourist SIM wins if you want maximum data per dollar, need a Thai phone number, or your phone doesn't support eSIM. On network quality there's no difference at all, since both use the same carriers.

Typical prices run $6–8 for 3–5GB over 30 days, $10–20 for 10–20GB, and about $28 for 50GB over 30 days. Unlimited plans cost more, $15 for 10 days from Nomad, and for a month $48.99 from Saily, $49 from Airalo and $73.90 from Holafly. Airport tourist SIMs cost ฿499–699, about $15–21, for 8–15 days of unlimited data. Better per gigabyte, but you buy it standing in line after a long flight.

Almost certainly. Thailand's networks use standard GSM/LTE/5G bands compatible with modern US, UK and other international phones. Two checks matter. The phone must be carrier-unlocked for any local SIM or eSIM (phones still on a carrier payment plan often aren't), and for eSIM it needs hardware support, meaning iPhone XS/XR or newer, Galaxy S20 or newer, or Pixel 3 or newer. Dial *#06#. An EID number means it's eSIM-capable. Some US plans include international data at no extra cost and some UK plans include Thailand in a higher tier, so check before paying $10–12 or £6–8 a day for roaming.

Airalo for most trips. It's got cheaper entry plans from about $4, a more mature app, and capped plans that suit normal maps-and-socials use. Holafly is the long-standing unlimited pick for heavy streaming, video calls or hotspot work, at $11.90 for three days up to $73.90 for thirty, though check its tethering cap first. Airalo's own unlimited Thailand plans undercut it at every length, $9.50 for three days to $49 for thirty, and Nomad's 10-day unlimited is cheaper again at $15, so the case for Holafly now rests on its support and on how each one behaves under heavy use rather than on price. All of them ride Thailand's main networks, so coverage is effectively identical.

For capped data, Airalo's 10GB at $11 or Saily's 10GB at $10.99 covers most month-long trips, with 20GB at $18–20 if you post a lot. For unlimited data over 30 days, Saily ($48.99) and Airalo ($49) cost the same and Holafly charges $73.90. Nomad's unlimited plan stops at 10 days. A ฿1,199 AIS or True tourist SIM is the other unlimited month, and it comes with a Thai number.

Yes. WhatsApp is tied to your phone number, not your data line, so it keeps working on your home number while the eSIM carries the data. Leave the home line switched on for calls and texts, set the eSIM as your data line, and WhatsApp, iMessage and your bank's app carry on as they do at home.

Most travel eSIMs are data-only, so there's no Thai phone number for Grab drivers, hotels or delivery apps to call. Your phone has to be unlocked and eSIM-capable. Moving an eSIM to another phone is harder than swapping a plastic SIM, so if your phone breaks you may need a new plan. And some plans start counting days the moment you install them, so check before you install too early.

Turn off data roaming on your home line, and turn it on for the eSIM. It sounds backwards, but a travel eSIM always connects as a roaming line, so it needs roaming on to work, and it won't run up charges from your home carrier. Your home line stays on for calls and texts with its data roaming off.

A little. Keeping two lines active means the phone stays connected to two networks, so battery life drops slightly. If you don't need bank texts or calls on your home number for a while, switching that line off in your settings gets the difference back.

Yes. AIS sells a tourist eSIM online and AIS and True sell tourist SIMs at airport counters, with a Thai phone number included (passport required for registration), and travel eSIM apps like Airalo work fine when you buy mid-trip over wifi. Buying before you fly is still the smoother play, though. You land already connected instead of hunting for wifi to fix the exact problem the eSIM was meant to solve.

Yes, for almost everyone. A $5–10 eSIM covers a typical two-week trip, installs at home in five minutes, and means maps, Grab, translation and bank codes work from the moment you land, versus £6–8 or $10–12 a day for home-carrier roaming, or an airport counter line for a physical SIM. The only people who should skip it are those whose home plan already includes free international data, or heavy users who need the airport SIM's unlimited data or a Thai phone number.

Only if your home plan includes free or cheap international data, and some genuinely do, so check first. Classic daily-rate roaming, £6–8 a day on EE, Vodafone, O2 or Three and $10–12 on T-Mobile, AT&T or Verizon, costs more per week than a whole month of Thai data, and O2's is capped at 2Mbps on top. Of all the options, it's the one clearly wrong answer.

Hotel and café wifi is good in tourist Thailand, but going SIM-free means no maps in taxis, no Grab bookings from the street, no translation on the go, and no bank codes if your bank sends SMS over cellular. At $5–10 for a whole trip's eSIM, connectivity is the cheapest problem you'll solve all vacation.