Quick verdict: eSIM vs AIS local SIM for Thailand
Short answer: for trips under 2 weeks, a Thailand eSIM from Flysimio is the most convenient option and competitively priced. For trips of 3–4 weeks, an AIS local SIM purchased at Bangkok Suvarnabhumi Airport (counter in arrivals hall) offers more data per baht — but requires showing your passport in person.
| Option | Best for | Approximate cost | Where to buy |
|---|---|---|---|
| Flysimio Thailand eSIM | Short trips (3–14 days); travelers who prefer booking in advance | $5.75 for 5 GB / 30 days | Online, before departure |
| AIS Tourist SIM | Long stays (3–4 weeks); maximum data per dollar | $15–$20 for 30 GB / 30 days (unlimited 1 Mbps) | AIS counter at Suvarnabhumi or Donmueang airport |
| DTAC Tourist SIM | Alternative to AIS; similar pricing | $12–$18 for 15–30 GB | DTAC counter at airport or 7-Eleven |
| True Move H Tourist SIM | Best urban 5G in Bangkok and Phuket | $15 for 30 days unlimited | TrueMove H shops; some airports |
| International roaming | Trips under 48 hours only | $10–$15 per day | Auto-active on home SIM |
Thailand eSIM comparison (2026)
| Provider | Plan | Price | Carrier | Price/GB |
|---|---|---|---|---|
| Flysimio | 5 GB / 30 days | $5.75 | AIS / DTAC | $1.15/GB |
| Flysimio | 10 GB / 30 days | $10.50 | AIS / DTAC | $1.05/GB |
| Airalo | 5 GB / 30 days | $11.00 | AIS | $2.20/GB |
| Nomad | 5 GB / 30 days | $9.00 | AIS / True Move H | $1.80/GB |
| Holafly | Unlimited / 30 days | $39.00 | True Move H | Unlimited |
| Saily | Unlimited / 30 days | $19.99 | AIS | Unlimited |
Thai carriers: AIS vs DTAC vs True Move H
Thailand has three main carriers. All three have good 4G coverage in Bangkok, Chiang Mai, Phuket, Pattaya, and Koh Samui. The differences show in rural areas and islands.
- AIS (Advanced Info Service): the largest carrier in Thailand. Best overall rural coverage including northern hill areas (Pai, Mae Hong Son), northeastern Isan region, and major islands. Recommended if your trip includes areas outside tourist corridors.
- DTAC (now merged into NTPLC): strong in Bangkok and major tourist cities. Note: DTAC and True Move H merged in 2023 — their networks are being integrated, which may affect roaming behavior on eSIMs from older providers using DTAC exclusively.
- True Move H: best 5G speeds in Bangkok CBD and Phuket City. Expanding rapidly. Strong for digital nomads in major cities.
Coverage on Thai islands: Koh Samui, Koh Phangan, Koh Lanta, Koh Tao
- Koh Samui: excellent 4G coverage on AIS and True Move H across the main areas (Chaweng, Lamai, Nathon). 5G expanding.
- Koh Phangan: good 4G in Haad Rin, Thong Nai Pan, and main beach roads. Some bungalow areas on the west coast have weaker signal.
- Koh Tao: 4G in Mae Haad and Sairee Beach. Signal drops in dive sites and forest trails — download offline maps.
- Koh Lanta: 4G in Saladan and Long Beach; patchy on the east coast and southern tip.
- Koh Chang: 4G in White Sand Beach and Klong Prao Beach. Signal weakens in interior and eastern coast.
Is it worth getting an eSIM for Thailand, or just buy AIS at the airport?
This is the most common question about Thailand connectivity, and the answer depends on your trip length and preference:
- Buy a Thailand eSIM if: your trip is 14 days or less, you want to set up data before you land, or you prefer not to queue at an airport counter.
- Buy AIS local SIM at the airport if: your trip is 3–4 weeks, you want maximum data (30+ GB), or you are comfortable spending 10–15 minutes at an AIS counter in arrivals.
- The AIS Tourist SIM at Bangkok airport costs approximately 500–700 baht ($14–$20) for 30 GB or unlimited 1 Mbps data for 30 days — more data per dollar than most eSIM plans for longer stays.
- Flysimio Thailand eSIM at $5.75 for 5 GB / 30 days is better value than AIS for short trips where you will not use 30 GB.
Which plan for your Thailand trip
| Trip length | Recommended option | Approximate cost |
|---|---|---|
| Weekend Bangkok (3–4 days) | Flysimio 3 GB / 7 days | $3.50 |
| 1–2 weeks in Thailand | Flysimio 5 GB / 30 days | $5.75 |
| 2–3 weeks island hopping | Flysimio 10 GB / 30 days | $10.50 |
| 3–4 weeks (long stay) | AIS Tourist SIM at airport (30 GB) | $14–$20 |
| Digital nomad (heavy data) | Saily Unlimited Thailand at $19.99 or AIS local SIM | $20–$25 |
Frequently asked questions
Is it worth getting an eSIM for Thailand?
Yes, for most trips. A Thailand eSIM from Flysimio at $5.75 for 5 GB beats international roaming ($10–$15/day) significantly. For longer stays of 3–4 weeks, an AIS local SIM at the airport offers more data per dollar, but an eSIM is more convenient for shorter trips.
Which is better for Thailand: AIS eSIM or DTAC eSIM?
AIS has the widest coverage in rural areas and islands. DTAC (now merging with True Move H) is strong in cities. For island-hopping or northern Thailand, choose an AIS-routed eSIM. For Bangkok-only trips, either network works.
Does a Thailand eSIM work on the islands (Koh Samui, Koh Phangan)?
Yes. Koh Samui and Koh Phangan have good 4G coverage in tourist areas. Download offline Google Maps before arriving on smaller islands where coverage is patchier. All eSIMs use the same carrier networks as local SIMs.
Can I buy an eSIM for Thailand at the airport?
No — eSIMs must be purchased online before you arrive. You need an internet connection to receive the QR code and install the eSIM. Buy your Thailand eSIM at least a day before departure, and install it on home Wi-Fi before boarding.
How much data do I need for 2 weeks in Thailand?
For typical tourist use (maps, social media, messaging): 5 GB is sufficient for 1–2 weeks if you use hotel Wi-Fi for streaming. If you stream a lot of video on mobile, 10 GB is safer. Download Spotify playlists and Google Maps offline to reduce usage.
Does Holafly Thailand unlimited eSIM actually give unlimited data?
Holafly unlimited plans typically include fair use throttling after a daily high-speed data cap. Check the current terms before purchasing. At $39 for 30 days, it is priced between AIS unlimited local SIM ($15–$20) and Saily unlimited ($19.99). Saily or a local AIS SIM offer better value for unlimited usage.