EU roaming on an Irish SIM, and a UK roam add-on, say nothing about Thailand. Roaming in Thailand vs eSIM is not a draw. Compatible unlocked mobile: take the eSIM, and turn data roaming off on the home line. The exception sits on this week's factsheet (Free Max, travel pass), not on a welcome SMS at BKK.
This guide compares home-carrier roaming and a travel eSIM for everyone: solo, couple, family, group, business, older travellers, teenagers. Thai hosts stay AIS, dtac and TrueMove H. Detail in the network guide. The airport box is a sibling piece: eSIM or pocket Wi-Fi. Plans sit on the Thailand comparison.
Supplier links are affiliates. They do not move the eSIM verdict or catalog prices. Detail in the methodology.
Roaming or eSIM in Thailand: the verdict
| Option | Who it is for | Strength | Traveller weakness |
|---|---|---|---|
| Travel eSIM | 1 to 3 compatible mobiles, 5 to 21 days | Host written, price per GB, install before Heathrow | Data only: no Thai number |
| Free Max (Thailand still listed) | Subscribers whose factsheet cites Thailand this week | Data on the line you already have | You do not pick the host. Voice often still billed. French SKU, not EE |
| Operator travel pass (e.g. 35 GB / 31 days) | Need to take voice calls on the home number | An add-on in the app, sometimes decent volume | Opaque host. This is not AIS |
| SFR / Bouygues travel packs | Voice calls on the home number | A pack in the app | Volume often too small. French SKUs |
| PAYG per MB | Nobody | None | French Orange public ladder: €13.31 per MB. Maps is not a test |
Rule: standard tariff (light UK PAYG, EE, Vodafone, Three, Tesco Mobile, giffgaff, or a standard EU plan): eSIM, home data roaming off. Free Max, or a SKU that writes Thailand: home data roaming can hold if you re-check the country list the week you fly. Operator travel pass: useful for voice on the home number, not for picking AIS or dtac. PAYG per MB: never.
Three eSIMs we track, useful once the phone passes the check:
CodeESIMP15
CodeSIMP
CodeESIMP
Who it is for: solo, family, Free Max, business
| Profile | Pick | Why |
|---|---|---|
| Solo, compatible iPhone / Pixel / Galaxy | eSIM | Maps + Grab, no PAYG ladder |
| Couple, two unlocked mobiles | 2 eSIMs (or 1 + tethering) | Two bars. One travel pass 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 | Home roaming does not become group Wi-Fi |
| Business, laptop | eSIM + tethering | An hour of video in Bangkok on EE PAYG has no human cap |
| Older traveller, uneasy with a QR | eSIM installed at home | The roam pass in the app is not simpler once PAYG opens |
| Teens on a cheap SIM | eSIM, home data off before boarding | Light UK PAYG carries almost nothing outside Europe |
| Free Max subscriber, Thailand listed | Home data roaming possible | Recheck the list. Keep SMS on that line anyway |
| EE / Vodafone, need home number voice | Travel pass or eSIM + WhatsApp | The pass wins on voice. The eSIM wins on host and €/GB |
| Mobile with no eSIM | Travel pass, plastic SIM or pocket Wi-Fi | The eSIM is not relevant. Check the model first |
A reader on Free Max is not "behind" if they stay on that line. They have a SKU that writes Thailand. The rest of this guide assumes the usual case: a home plan that does not include the Kingdom.
What EU roaming does not cover
Since 2017, "roam like at home" stops at the EU border (plus some extras by carrier: UK on some Irish SIMs, Switzerland, sometimes Ukraine). Thailand is not in that zone. A plan that "works in Spain" says nothing about a Maps refresh on Sukhumvit. Asia is not "almost Europe" for data. A UK post-Brexit roam pass is a different product again.
At landing, EE, Vodafone, Three or your EU carrier often send a welcome SMS. That is not a plan. It is a price list in a text. Out-of-bundle data outside Europe is billed per MB, in small increments. On French Orange the public ladder is about €13.31 per MB. EE, Vodafone and Three PAYG is the same idea in pounds.
A Maps session plus two stories is no longer a "quick test". It is a restaurant bill without the pad thai.
AIS is not that SMS. It is a local MNO. Your EE or Vodafone line sometimes attaches to it in roaming. You do not pick the host. An eSIM, if you read the column, does.
EE, Vodafone, Three, EU SIMs: the home factsheet
You are not buying "EE's Thai network". You are buying this week's roaming agreement on your SKU. Hosts behind it are still AIS, dtac, TrueMove H. The carrier app almost never names them. On our side the host networks column does, for the eSIM.
EE, Vodafone, Three, Tesco, giffgaff
Standard UK tariffs do not pour Thailand data out of the UK allowance. Without an add-on, it is PAYG per MB.
Carriers sell travel passes / roam extras (day or trip). A few GB, sometimes minutes, short validity. Useful if you must answer the UK number from a Bangkok hotel. Less useful for ten days of Maps, translate and Reels: price per GB on a Thailand eSIM, in the catalog, almost always wins.
giffgaff and many MVNOs are stricter: nothing useful outside Europe unless you buy a bolt-on. Treat a welcome SMS as a warning, not a bundle.
Ireland and other EU SIMs
Same rule as Spain or Germany: EU roaming ≠ Thailand. Vodafone IE, Three IE, eir, or a French Orange métropole SKU: eSIM, home data off. The French Free Max SKU is the textbook exception if Thailand is still on the country list. It is not EE. It is not Three Go Roam.
Voice is not the data pass
Even when a world tariff includes Thailand data, outbound and inbound voice is often still billed per minute. WhatsApp / FaceTime on data skip that line. A Thailand eSIM does not take your bank SMS: keep the home line on for Monzo, Revolut, high-street OTPs, HMRC, PayPal.
The move: eSIM before Heathrow, home number on
Open the compatibility tool before you buy a QR.
Install the profile on home Wi-Fi, or at Heathrow / Gatwick. On arrival: data = Thailand eSIM. Data roaming off on the home SIM. Data roaming on on the travel eSIM if the profile asks for it. Leave the home number on for bank SMS.
Pocket Wi-Fi and a local SIM are plan B. See eSIM vs pocket Wi-Fi and eSIM vs local SIM.
| Provider | Typical host | Code | Offer | Review |
|---|---|---|---|---|
| Airalo | AIS (often) | ESIMP15 | Offer | Review |
| Ubigi | check live | ESIMP | Offer | Review |
| Holafly | check live | SIMP | Offer | Review |
 Orange Travel | check live | ESIMP | Offer | Review |
 Nomad | check live | ESIMPNOMAD | Offer | Review |
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
- Thinking EU roaming works in Bangkok
Italy yes, Thailand no. A welcome SMS at BKK is not a plan. It is often the PAYG per MB rung.
Compare Thailand eSIMs - Leaving EE / Vodafone / Three data on « just in case »
PAYG per MB outside Europe. Switch off data roaming, not the line: bank SMS still need to land.
Compare Thailand eSIMs - Mixing a world SKU with a basic home tariff
Thailand may sit on a rare world list. A basic EE or Three plan carries almost nothing outside Europe. Recheck the country list.
Check compatibility - Switching off the UK SIM « to avoid roaming »
You lose Monzo, Revolut, HMRC OTPs. The Thailand eSIM is data only. Switch off data, not the number.
Check compatibility - Taking a 1 GB roam pass for Bangkok plus islands
Calculate the GB. A voice pass of a few MB does not save Maps. An eSIM host is readable, a pass host rarely is.
Calculate GB
FAQ
Does my UK or EU roaming work in Thailand?
EU roaming says nothing about Thailand. A UK roam pass is a different product again. EE, Vodafone, Three and most EU tariffs bill PAYG per MB unless a travel pass or a SKU lists Thailand. Check the factsheet the week you fly.
Thailand roaming vs eSIM: what should I get?
Compatible phone: travel eSIM, home data roaming off. Exception: a world tariff if Thailand is still on the list. A carrier travel pass is mainly for voice on the home number. It is not a draw with the eSIM: the eSIM host is readable.
Does Free Max include Thailand?
It is a French example (Iliad), not an EE product. It shows the exception: only if your SKU writes Thailand this week. Recheck the country list in the account before you land at BKK.
How much is PAYG data in Thailand?
French Orange publishes about €13.31 per MB outside Europe. UK PAYG is the same idea in pounds. A Maps session on Sukhumvit is not a small test.
Can I keep EE for bank SMS?
Yes. A Thailand eSIM is almost always data only. Keep the home SIM or eSIM for Monzo, Revolut, HMRC OTPs. Switch off data roaming only, not the line.
Is Orange Travel the same as EE roaming?
No. Orange Travel is a travel eSIM, a reseller. AIS, dtac or TrueMove H is the access network. A roam pass is roaming of your home line. Three products. Read the host.
Sources
All external sources open in a new tab.
- Orange FR, travel pass; out-of-bundle data outside the EU €13.31 / MB (operator / comparison grids 2026). UK PAYG is the same logic in £. Recheck your contract before boarding.
- Free Mobile, tariffs abroad (Thailand on Max data destinations: recheck).
- Opensignal, Thailand Mobile Network Experience Report, August 2026.
- eSIM Giga catalog: Thailand comparison (price, hosts, hotspot).
- Sibling guides: best mobile network in Thailand, eSIM or local SIM, eSIM or pocket Wi-Fi, Internet in Thailand.
A travel eSIM and a home line in roaming often ride the same MNOs. What changes is the price per MB, the host you can read, and the bank SMS. Once the phone is compatible, we stay on the eSIM.