Thailand Travel eSIM Networks: AIS, True Move and DTAC Explained

Why Thai SIM registration is stricter than most of Asia

Most destinations make the local SIM slightly inconvenient and slightly cheap. Thailand makes it genuinely awkward, and the rules now stack up.

Every Thai SIM and eSIM must be registered in real name, which for a visitor means presenting an original passport rather than a photocopy. Since 18 August 2025 carriers have also had to run biometric facial verification at the point of registration, so the process includes a face scan. Foreign visitors may register at most three SIMs or eSIMs per operator. The rules are set and enforced by the NBTC, Thailand’s telecom regulator. Add a queued airport counter after a long flight and the calculation changes.

Then there is the time limit, which catches longer stays. Since 30 August 2025, tourist SIMs are capped at 60 days of use, and topping up does not extend the cap — continued use requires going through re-identification with the carrier.

A travel eSIM bought before departure has none of those properties: no registration, no face scan, no 60-day ceiling, and no counter. That is the entire argument for a Thailand eSIM, and it is unusually strong here. Our Thailand plan comparison ranks the products on price and allowance rather than on paperwork.

How AIS True Move and DTAC divide the Thai market

Thailand has a structural wrinkle worth understanding first: True and DTAC merged in 2023 but continue to operate as separate brands with distinct network policies, so they share infrastructure while measuring differently. That is why the two independent firms report them inconsistently, and why the scoreboard above needs reading with care.

AIS is the Thai coverage and quality leader

Opensignal’s August 2026 report made AIS the most awarded operator, with seven sole wins and three shared, including Consistent Quality at 75.1%, Upload Speed at 15 Mbps, and both Coverage Experience categories. Ookla named it the fastest mobile network in Thailand for the first half of 2026 with a Speed Score of 70.6 against True dtac’s 66.4. If your trip includes islands, this is the network you want underneath.

DTAC is the Thai value speed performer

DTAC shares the Best Network award with True, won Reliability outright at 907 points out of 1000, and took the fastest overall downloads at 41.1 Mbps and 5G Download at 102.7 Mbps — overtaking AIS in both. DTAC is the budget-first choice and holds up well in Bangkok and the north.

True Move owns Thai 5G availability

True Move recorded 90.2%, the highest share of time a user with a 5G device actually detects a 5G signal. In practice it shares both the Best Network award and the physical network with DTAC.

All 8 travel eSIM brands we track connect to all three, so no provider can sell you better Thai coverage. The brand table below shows it row by row.

The two columns rank the same carriers using different evidence, one averaging real-user experience nationally and the other taking the median of voluntary speed tests. Neither predicts your own throughput, which also depends on congestion, your device and which bands it supports.

The 60-day cap on Thai tourist SIMs

A Thai local SIM is worth the effort only for a long stay rather than a holiday. Here is what you are signing up for.

The 60-day cap is the detail most visitors miss. If you are staying longer, either plan to re-identify with the carrier or buy your data in stages, and check what the plan’s own validity allows rather than assuming it can be topped up indefinitely.

Island coverage and which Thai network is best for islands

Thailand’s geography makes coverage a practical question rather than a technical one, because a large share of visits involve water.

That last row is worth a moment. Along Thailand’s land borders, phones sometimes pick up a neighbouring country’s network, which on a country-specific plan means either no service or an unexpected charge. AIS has the most consistent domestic footprint in those areas.

The NBTC has ordered AIS and True to submit roadmaps for shutting down 2G and 3G by the third quarter of 2026, and stopped approving 2G and 3G-only device imports in August 2025. Bring a 4G or 5G handset with VoLTE and none of this will affect you. An eSIM is a download rather than a physical card, a standard maintained by the GSMA, and it runs on whatever bands your phone supports. The eSIM compatibility checker covers the model detail.

Sizing a Thailand eSIM data plan for island hopping

All three carriers we track list 5G, so the technology is not a differentiator between brands. Where it matters is the pace of improvement: DTAC raised its 5G download by 13 Mbps in a single reporting cycle to overtake AIS at 102.7 Mbps, and Thailand’s June 2025 spectrum auction added substantial new capacity. Thai 5G is getting faster rather than settling.

For a visitor the useful checks are narrower. Does the plan list all three carriers, which protects you on the smaller islands. Does it allow hotspot sharing if you are travelling as a pair. And does the allowance match the length of the trip, because map apps and photo uploads add up faster than most people expect on a beach holiday.

Our ranking of Thailand eSIM plans sorts every plan we track by price per gigabyte and per day, and the trip cost calculator will estimate an allowance from your apps and dates. Live discounts sit on the this month’s eSIM deals.

Three practical notes. Thai spectrum is licensed nationally and the bands in use differ from Europe’s, so confirm your handset supports them. Thailand sits outside any regional roaming arrangement, which means a home SIM used here bills at international rates and a prepaid plan bought locally carries its own fair-use terms. If you end up buying that local prepaid SIM as a backup, the face scan and the 60-day limit both apply to it.