In Thailand you almost never buy "an eSIM network". You buy access to a local operator: AIS, dtac, TrueMove H. The eSIM brand (Airalo, Holafly, Ubigi, Nomad) is a reseller. If the plan sits on the wrong host for your route, Maps drops on Koh Tao, Grab crawls in Pai, and the "5G" on the pack does nothing.
This guide ranks the three Thai MNOs for a visitor, not a local subscriber. Scores come from field experience studies (Opensignal, Thailand report August 2026), subscriber volumes (AIS / True releases, NBTC framework), and the host each travel eSIM declares, the same field as the networks table on the Thailand comparison.
Supplier links are affiliates. They do not move the network ranking or the catalog prices. Detail in the methodology.
AIS, dtac or TrueMove H: which network in Thailand?
| Rank | Network | Who it is for | Measured strength | Traveller weakness |
|---|---|---|---|---|
| 1 | AIS | Islands, north, Isan, roads outside Bangkok / Phuket | Consistent Quality 75.1%, coverage, upload 15 Mbps, Voice App | Not the 2026 Best Network title (dtac + TrueMove H) |
| 2 | dtac | Bangkok, Chiang Mai, day-to-day (Grab, Maps, WhatsApp) | Reliability 907 / 1000, download 41.1 Mbps, 5G download 102.7 Mbps | Same True Corporation radio as TrueMove H: read the SKU |
| 3 | TrueMove H | Dense cities, time on 5G | 5G Availability 90.2%. Shared Best Network with dtac | Consistent quality behind AIS (66.0%) |
Simple rule: pick AIS if the itinerary leaves Bangkok, Chiang Mai and Phuket town. Pick dtac if you want the most reliable day-to-day connection. TrueMove H is the "time on 5G" pick in agglomerations. dtac and TrueMove H belong to True Corporation: 2023 merger, integrated radio (One Network, 2025). Opensignal still measures them separately. A multi-host AIS + True/dtac plan reassures as soon as you mix malls and islands.
Who it is for: solo, family, group, business
| Profile | Host pick | Why |
|---|---|---|
| Solo, compatible iPhone / Pixel / Galaxy | eSIM, AIS host or multi | Maps as you leave the BKK / DMK runway |
| Couple, two unlocked mobiles | 2 eSIMs (or 1 + tethering) | Two bars. One local prepaid does not save the second phone |
| Family, kids / tablets | Adult eSIMs + hotspot | Bank, Revolut, Monzo, PayPal and HMRC OTPs stay on the home line |
| Group of 5+ | eSIM or pocket Wi-Fi | One group Wi-Fi, not five UK or EU roam bills |
| Business, laptop | eSIM + tethering, aim at dtac speed | An hour of video on Sukhumvit on EE PAYG has no human cap |
| Older traveller, uneasy with a QR | eSIM installed at home | The BKK desk is not simpler once the queue exists |
| Teens on a cheap SIM | eSIM, home data off before boarding | A light UK PAYG or Irish SIM carries almost nothing outside Europe |
| Mobile with no eSIM | Plastic SIM or pocket Wi-Fi | The eSIM is not relevant. Check the model first |
A reader with no eSIM radio is not "behind". They need a different tool. The rest of this guide assumes a compatible SKU, the usual case on our catalog.
What the studies actually measure
Opensignal: experience, not 5G ads
The Thailand report for August 2026 aggregates user measurements from 1 April to 29 June 2026. This is not a lab drive test. It is what phones see in the wild.
Figures that matter for a traveller:
- AIS: most awarded operator (seven solo wins). Consistent Quality 75.1%. Wins Coverage Experience, 5G Coverage Experience (5.5 / 10), Upload Speed 15 Mbps, 5G Upload 21.8 Mbps, Voice App 82. 5G Advanced launched in May 2026 (700 / 2100 / 2600 MHz aggregation).
- dtac: Reliability Experience 907 points (14 ahead of AIS). Download Speed Experience 41.1 Mbps (0.3 Mbps ahead of AIS). 5G Download 102.7 Mbps. Shared Best Network with TrueMove H.
- TrueMove H: 5G Availability 90.2%. Shared Best Network. Consistent Quality 66.0%, third place.
The BKK–Chiang Mai–Phuket corridor is not a mobile desert. Think Tube coverage there. The delta sits at the margin: Koh Tao, stretches of Krabi, Pai, Isan, ferries, the Koh Lanta coast. That is an island branch line, not Zone 1.
Market share: who actually has the most lines
Opensignal experience is not market share. True Corporation (TrueMove H + dtac) holds the largest combined base, around half of all lines (mid-2025 order of magnitude: ~48.5 to 49.4 million). AIS published 47.1 million mobile lines in Q2 2026 (AIS release). National Telecom (NT) is negligible for a visitor.
Do not mix market share with quality. AIS is no longer always #1 on lines. It remains the geographic safety net. For an eSIM: if the host is not AIS, dtac or TrueMove H, ask.
What carrier roaming does not tell you
Staying on EE, Vodafone, Three, Tesco Mobile, giffgaff or an Irish / EU home tariff in Thailand is often dearer for a weaker radio. EU roaming does not cover Thailand. A UK post-Brexit roam pass is a different product again. Detail in the roaming guide.
TrueMove H is not "True" as an eSIM brand. A welcome SMS at BKK almost never names the host. On our side the host networks column does, for the eSIM.
Detailed ranking of the three networks
1. AIS, the safety net
AIS does not crush dtac on download in town. It wins where a traveller suffers the network: Koh Tao, the road to Pai, Isan, the coast between Krabi and Koh Lanta, night transfers.
If your eSIM lists AIS or AWN (AIS), you have the "I do not want to debug Maps at 10 pm" profile. That is eSIM Giga's default once the itinerary is not 100% urban.
On 5G, AIS pushed coverage beyond 95% of the population (operator figure) and 5G Advanced in May 2026. On an island you drop back to 4G LTE. That is normal, even on a plan stamped 5G.
Three eSIMs we follow that often host Thailand plans on AIS (check the host column of the table at purchase):
CodeESIMP15
CodeESIMP
CodeESIMPNOMAD
2. dtac, the best typical day in town
dtac wins the daily grind: Grab in a tuk-tuk, Google Translate at the market, WhatsApp, Reels. Reliability and download are the metrics that avoid "I have four bars and nothing loads".
Good match for Bangkok, Chiang Mai, Phuket town. Less reassuring once you leave the tarmac, unless the SKU is multi-host with AIS. A dtac or TrueMove H SKU often rides the same True Corporation radio.
Three eSIMs we follow if you want dtac or a multi-host plan:
CodeSIMP
CodeESIMG
CodeESIMP15
3. TrueMove H, time on 5G, not the net
TrueMove H is the network if you measure the trip in minutes of 5G: laptop hotspot in a Bangkok coworking space, video calls, backups. 5G Availability at 90.2% means, of the three, this is where Opensignal most often sees an active 5G carrier. It is not theoretical 5G coverage on a marketing map.
Outside the big agglomerations that bonus melts. Take TrueMove H as a sole host only if you stay on urban corridors, or if the SKU adds AIS.
2022 trap: "dtac is dead, take True". The brands still exist. Opensignal separates them. Read the live label.
Three eSIMs to check if the Thailand SKU names True, dtac or a host trio:
CodeESIMP
CodeESIMP
CodeESIMPNOMAD
From the local operator to the eSIM: what you actually buy
So far we talked AIS, dtac, TrueMove H. Those are Thai subscriber networks. A travel eSIM is not an AIS contract. It is an MVNO / aggregator that rents capacity on one (or several) of those hosts.
For the eSIM vs plastic SIM desk match, see the dedicated guide. For 10 days of holiday the travel eSIM almost always wins on friction. The local SIM wins if you stay months or need Thai SMS.
Where to read the host on our site
Product pages often say "Thailand 5G". The useful field is the host operator. On eSIM Giga we normalise it (AIS, dtac, TrueMove H) from supplier labels. That is the "Host networks" column of the Thailand networks table: a provider, the average price per GB, and the hosts declared on the plans we analysed.
Three patterns show up in that table:
- A single host (often AIS). The most readable: you know which network you will be on.
- Multi-host (AIS + TrueMove H, sometimes dtac). The phone latches onto the best signal. Most reassuring format outside town.
- "Partners in Thailand" with no name. Unknown spread: possible, but you are no longer buying a network, you are buying a hope.
Airport pocket Wi-Fi (BKK / DMK / HKT) also rides these three MNOs. They lose on two points: a queue and another device. An eSIM installed before Heathrow or Gatwick stays the cleanest move. Some EE, Vodafone, Three or Tesco Mobile Androids have no eSIM: use the compatibility tool, not "every iPhone 14 and later".
Recap table: eSIMs, networks, promo codes
Host "often declared": cross-check with the live table. The same provider sometimes has several Thailand SKUs.
| Provider | Typical host | Code | Offer | Review |
|---|---|---|---|---|
| Airalo | AIS (often) | ESIMP15 | Offer | Review |
| Ubigi | check live | ESIMP | Offer | Review |
| Holafly | check live | SIMP | Offer | Review |
| Nomad | check live | ESIMPNOMAD | Offer | Review |
| Saily | check live | ESIMG | Offer | Review |
| Orange Travel | check live | ESIMP | Offer | Review |
| GigSky | multi-host (often) | ESIMP | Offer | Review |
How to choose in 60 seconds
- Draw the map. Only Bangkok + Chiang Mai + Phuket town: dtac or TrueMove H often holds. As soon as you add Koh Tao, Pai, Isan, Koh Lanta: AIS (ideally multi-host).
- Open the live comparison: Thailand eSIM, sort €/GB for limited plans, total price for short stays.
- Read the host in the networks table, not the word 5G. A TrueMove H 5G on Koh Tao at night is not an AIS 4G that actually connects.
- Install before the flight. BKK / DMK Wi-Fi exists. Scanning a QR in a jet-lag queue is worse.
- Keep the home line for bank SMS (data-only eSIM).
- Turn off iCloud / Google Photos backups on cellular unless you bought a large pack or unlimited with fair use you actually read.
Estimate gigabytes for maps, video and hotspot.
Open calculatorPHONEeSIM compatibilityCheck iPhone, Pixel and Galaxy before you buy. EE, Vodafone or Three SKUs are not always eSIM.
Check my phoneHow much data for your trip in Thailand?
Three typical trips, same maths as the calculator, Southeast Asia factor. Maps, Grab, Reels or a laptop on tethering: the same gigabytes on an eSIM or a pocket Wi-Fi box. Turn off photo backup on cellular if you want the low end. Read the fair use.
Estimate 8.3 GB · Maps, chat, Instagram. No Reels, no laptop.
Estimate 16.5 GB · Same base, plus half an hour of video a day.
Estimate 31.6 GB · One hour of phone tethering a day for the computer.
Mistakes that still cost money
- Buying an « Asia » eSIM for 4 days in Bangkok
You pay for countries you will not use. Stay on a Thailand plan.
Thailand-only plans - Staying on UK roaming « because it is simple »
The PAYG per MB rung explodes. An eSIM on AIS or dtac is often cheaper, with a written host.
Compare Thailand eSIMs - Mixing up TrueMove H and dtac from a 2022 article
Same group, radio often shared. An eSIM host is in the table. AIS remains a distinct network.
Host table - Taking too little GB, or unlimited for the word
Maps + Grab + Reels + photo backup swell fast. Unlimited without tethering does not save a laptop. Fair use exists in Thailand too.
Calculate GB - Scanning the QR on a financed EE or Vodafone Android
Some UK SKUs have no eSIM. Check before you pay, not at BKK.
Check compatibility
FAQ
What is the best mobile network in Thailand for a traveller?
AIS for coverage outside the cities and consistent quality. dtac for reliability and download speed. TrueMove H for time spent on 5G. A travel eSIM only inherits that host if the plan writes it. dtac and TrueMove H often share the same True Corporation radio.
How much data do I need for Thailand?
Maps, chat and social for a week in town: a 10 GB plan often holds. Reels and photo backup over 10 days: closer to 20 GB. Laptop hotspot for two weeks: 30 to 50 GB. The calculator applies the South-East Asia factor.
Travel eSIM or a Thai carrier SIM?
For 5 to 21 days, the travel eSIM wins on friction. A local SIM (AIS, dtac, TrueMove H) wins for a long stay or a Thai number. Detail in the eSIM vs local SIM guide.
Does 5G work in Thailand in 2026?
Yes, mostly in cities. Opensignal (August 2026) measures TrueMove H at 90.2% 5G availability. AIS launched 5G Advanced in May 2026. On Koh Tao, Koh Lanta or parts of Krabi, you fall back to 4G. That is normal, including on a plan stamped 5G.
Are dtac and TrueMove H the same operator?
Same group (True Corporation), radio integrated (One Network 2025). Opensignal still ranks them separately. An eSIM SKU may write only one of the two names. Read the hosts column.
Where do I read the host network of a Thailand eSIM?
On eSIM Giga, in the Thailand comparison networks table, Host networks column. Not on the word 5G on the packaging. The same provider sometimes has several SKUs.
Sources
All external sources open in a new tab.
- Opensignal, Thailand Mobile Network Experience Report, August 2026 (collection 1 April to 29 June 2026).
- AIS, Q2 2026 results: 47.1 million mobile lines.
- True Corporation: True / dtac merger (2023), One Network project completed 2025 (Opensignal August 2026 summary).
- eSIM Giga catalog: Thailand comparison (prices, hosts, declared 5G, hotspot).
- Sibling guides: eSIM or local SIM, eSIM or pocket Wi-Fi, Internet in Thailand, roaming or eSIM.
Opensignal figures describe local networks. A travel eSIM only inherits them if the host is the one announced. And even then: QoS, fair use and MVNO priority can put your session far from a postpaid AIS subscriber. Reflex: host first (Thailand table), €/GB next, promo last.