Best eSIM for Thailand: Bangkok, the islands and the north compared

Which Thailand eSIM fits your trip?

Start from the kind of trip, not from the price tag:

• Bangkok and a beach for a week: 3 to 5 GB is enough for Grab rides, maps, messaging and photos. Hotels and cafés almost always have Wi-Fi.
• Two to three weeks of island hopping: 10 to 20 GB, or an unlimited plan with at least 2 GB per day at full speed if you post videos or work on the road. Make sure the validity covers the whole trip.
• A month or more in Chiang Mai or Bangkok: look at 30-day plans with 20 GB or more, or a long unlimited plan, and compare the price per day.
• Thailand plus Vietnam, Cambodia or Malaysia: a Southeast Asia regional plan often beats buying a second eSIM at the border.

Two features are close to standard in Thailand: well over half of the plans we track include 5G, and practically every plan that states a hotspot rule allows tethering, so you can share the connection with a laptop or a travel partner. Plans with a phone number are rare, which only matters if you need to receive calls (more on that below).

The figures in the boxes and tables are pulled from our database every time the page loads, so they show today's market rather than the day this guide was written.

Thailand eSIM prices by data amount

Each row is the cheapest plan we track for that amount of data with at least a week of validity. Compare the price per GB rather than the headline price: in Thailand a 10 or 20 GB plan often costs only a little more than a 3 GB one, so sizing up is cheap insurance.

Two things are easy to miss. First, some of the cheapest rows can be regional plans for Southeast Asia or Asia; they work exactly the same in Thailand and are worth it if your trip continues to a neighbouring country. Second, the validity starts at different moments depending on the provider, usually at the first connection in Thailand. A 15-day plan on a 16-night holiday means buying a top-up on the last day.

AIS, True or dtac: which network covers Thailand best?

Thailand has two large mobile groups. AIS runs one of them, with broad national coverage. True and dtac merged in 2023 and now belong to the same company, True Corporation, although both brands and network names still appear on eSIM plans (“TrueMove H”, “dtac TriNet”). The state-owned operator NT plays a minor role for travellers.

All of them are fast in Bangkok, Pattaya, Phuket town, Chiang Mai and the other big centres, and 5G is common in the cities. The differences show up on smaller islands, in national parks and in the mountains of the north. If your route goes off the main tourist trail, a plan that can connect to both AIS and True/dtac gives the phone a second option when one network is weak. Plans that name only one network are usually fine for cities and the main beach areas.

The network list comes from the providers and is shown on every plan on our Thailand page.

Unlimited data in Thailand: read the daily limit

Unlimited plans are popular for Thailand, and most of them follow the same pattern: a fixed amount of data at full speed every day, then a slower connection until midnight. In our data the most common rules give between 1 and 3 GB per day at full speed and then drop to 384 kbps or 1 Mbps. At 384 kbps, messaging and maps still work, but video and photo uploads stall; at 1 Mbps, social media stays usable.

The left column is the cheapest unlimited plan for each trip length, whatever its daily limit. The right column only counts plans with at least 2 GB per day at full speed. If you film on the beach, stream music on long bus rides or share the connection with a laptop, the right column is the fairer comparison; if you mostly use maps and chat apps, a fixed-data plan is usually cheaper than either.

Coverage on the islands, at sea and in the north

Most visitors spend at least part of the trip on the coast, and that is where expectations and reality can differ:

• Popular islands such as Phuket, Koh Samui, Koh Phangan, Koh Phi Phi and Koh Lanta have good coverage around the towns and main beaches. Small bays, viewpoints and the far side of an island can be patchy.
• On ferries and speedboats the signal often drops in the middle of the crossing. Download your boat ticket, hotel address and offline map before you leave the pier.
• Marine parks, dive sites and remote national parks can have weak or no signal. Plan them as offline days.
• The north around Chiang Mai, Chiang Rai and Pai is well covered in towns; on mountain roads and in rural villages, a plan with two networks helps.

None of this is specific to eSIMs: local SIM cards use the same towers. The advantage of an eSIM is that you can pick a plan with more than one network and keep your home SIM in the phone.

Airport tourist SIM vs travel eSIM

At Bangkok's Suvarnabhumi and Don Mueang airports and at other major airports, operator counters sell tourist SIM cards after passport control. They work well, so is an eSIM still worth it?

The tourist SIM is a good choice if you need a Thai number for a long stay. For most holidays, the eSIM saves the queue and keeps your own number reachable.

Grab, LINE and a phone number: what you need

A few apps make Thailand much easier, and all of them run on mobile data:

• Grab or Bolt for taxis and motorbike rides, with prices fixed before you get in.
• Google Maps for walking routes, the BTS Skytrain and MRT, and finding food stalls.
• LINE, the messaging app many Thai hotels, tour operators and shops use for bookings.

Most travel eSIMs are data only, which is no problem for these apps. The one catch is the SMS verification code some apps send when you sign up: create your accounts at home, while your own number receives texts. If you do need a Thai or international number for calls, a few providers sell Thailand plans with voice and SMS; filter for them on our Thailand comparison.

Setting up your eSIM before you fly

• Your phone supports eSIM and is unlocked; our guide How to check if your phone supports eSIM takes a minute.
• The eSIM is installed over Wi-Fi at home (QR code or the provider's app), and you know when its validity starts.
• On arrival you switch the eSIM line on, allow data roaming for it and select it for mobile data.
• Your home SIM stays on for calls and SMS, with its data roaming switched off to avoid your carrier's charges.
• Offline maps of Bangkok and your islands are downloaded, and app accounts are verified.

Travelling further in the region? Compare Vietnam, Cambodia and Malaysia plans, or a single Asia regional eSIM. Current discount codes are on our promo code page.