Can a Thai SIM Card Work in Laos? AIS, DTAC & True Roaming

Yes. A Thai SIM card from AIS, DTAC or True can work in Laos through international roaming. Once you cross the border, your phone connects to a Lao partner network, as long as roaming is on and you have a package that includes Laos. Your Thai number stays with you, and you keep receiving the codes and messages sent to it.

So the real question is not whether your Thai SIM works in Laos. It is what it will cost, how well it works once you leave the border area, and whether a local option would serve you better. Standard pay-as-you-go roaming can be very expensive, so the one rule that matters is to buy a roaming package before you cross.

This guide is built from what the operators themselves publish (True, dtac and AIS), from traveler reports on Reddit’s r/laos, and from what we see selling connectivity in Laos every day. Where a fact is official we say so, where it comes from travelers we label it as anecdotal, and where we could not verify something we say that too. The last section lists every source with its date.

Thai SIM in Laos: the quick answer

Thai operator	Works in Laos?	What you need	What to check first
AIS	Yes	A Ready2Fly roaming package, from 169 baht + VAT for 3GB over 7 days, bought before you cross	Current price and validity in the AIS app
DTAC (now True)	Yes	A GO Travel package bought in the True App	Whether your SIM appears in the True App and the package lists Laos
True (TrueMove H)	Yes	A GO Travel package that lists Laos	Consumer price and allowance in the True App

Three things decide how your trip goes: whether you bought a package before crossing, where in Laos you are, and how much data you use. The rest of this guide covers each.

How does a Thai SIM connect to Lao networks?

Roaming: your Thai SIM on a Lao partner network

Your Thai SIM stays the same SIM and keeps your Thai number. When you cross the border, your phone registers on a Lao mobile network that has a roaming agreement with your Thai operator (commonly Unitel or Lao Telecom). You use Lao coverage, and your Thai operator bills you for it.

Two consequences follow. First, the price and allowance are set by your Thai operator, not by Laos. Second, actual speed depends on the Lao network you attach to, and True’s published terms say the same: packages work only on participating overseas networks, and speed depends on the visited operator.

Thai signal near the Mekong is not roaming

Travelers on r/laos report that Thai service reaches the Vientiane riverfront, sometimes even indoors near the Mekong, and fades a block or two inland. One frequent cross-border traveler called it “spotty and unreliable”. That is spillover from Thai towers across the river, not a service you can plan on. It can also drain your battery while the phone hunts for a network.

If your phone shows a Thai network name on the Laos side of the river, do not assume you are roaming. Check that your roaming package is active and that data roaming is on before you rely on it.

Which Lao network will my Thai SIM use?

It depends on your operator’s agreements and on where you are. AIS lists four roaming networks in Laos: Beeline, ETL, Lao Telecom and Unitel, with voice, receiving calls, data and SMS available on all four (details in the AIS section below). True and dtac do not publish an equivalent Laos network table on the pages we could read, and community reports commonly name Unitel or Lao Telecom for Thai SIMs. Your phone’s network settings show the partner networks available to you in Laos.

Can AIS work in Laos?

Yes. AIS lists Laos on its roaming pages, with Ready2Fly packages, pay-per-use rates and four Lao roaming networks. This is the most detailed official information any of the three operators publishes for Laos, so we quote it in full.

AIS Ready2Fly packages that list Laos

AIS’s Laos roaming page lists the packages below, all under its “Asia & Australia” region. Prices exclude 7% VAT, and prepaid customers must top up the full amount. Data is shown “at max speed”, meaning the high-speed allowance.

Package	Data	Validity	Calls and SMS	Price	Register
Ready2Fly Border	3GB	7 days	None listed	169 baht	*111*169#
Ready2Fly	8GB	10 days	None listed	449 baht	*111*449#
Ready2Fly Plus + Travel Insurance Plan 1 (250,000 baht cover)	10GB	10 days	15 min	599 baht	*111*2014#
Ready2Fly	15GB	10 days	None listed	649 baht	*111*15649#
Ready2Fly Plus + Travel Insurance Plan 2 (500,000 baht cover)	12GB	10 days	15 min	699 baht	*111*2015#
Ready2Fly Plus + Travel Insurance Plan 3 (1,000,000 baht cover)	15GB	10 days	15 min	799 baht	*111*2016#
Ready2Fly	20GB	15 days	None listed	849 baht	*111*20849#
Ready2Fly Premium	15GB	10 days	60 min + 30 SMS	1,290 baht	*111*42#
Ready2Fly Premium for Serenade	35GB	20 days	120 min + 120 SMS	2,290 baht	*111*16#
Ready2Fly Premium	35GB	20 days	120 min + 120 SMS	2,490 baht	*111*15#
Ready2Fly Beyond for Serenade	100GB	50 days	500 min + 500 SMS	4,590 baht	*111*186#
Ready2Fly Beyond	100GB	50 days	500 min + 500 SMS	5,590 baht	*111*85#

What this means for a trip to Laos:

• For a short stay, Ready2Fly Border is the entry point: 3GB for 7 days at 169 baht. For a longer or heavier trip, the plain Ready2Fly options run from 8GB for 10 days (449 baht) to 20GB for 15 days (849 baht).
• The Plus packages bundle travel insurance and 15 minutes of calls. Premium and Beyond bundle calls and SMS, and AIS says they also include free unlimited in-flight roaming (register with *111*5*70#). Serenade members get cheaper versions of Premium and Beyond.
• When it starts: a Ready2Fly package begins counting the first time you connect to an overseas network. If you have not used it within 60 days, AIS cancels it automatically and does not charge the package fee.
• SIM2Fly, AIS’s travel SIM, lists Asia and Australia options of 6GB for 10 days and 13GB for 10 days (with free calls), and a worldwide 15GB for 30 days at 1,599 baht. The page shows no price for the two Asia options, so we do not quote one.

AIS pay-per-use rates in Laos

If you roam without a package, AIS charges these rates, excluding 7% VAT:

Service	Rate
Local calls	16 baht per minute
Calls to Thailand	32 baht per minute
International calls	46 baht per minute
Receiving calls	26 baht per minute
SMS	17 baht per SMS
Data	0.0049 baht per KB
Receiving SMS	Free

The data rate is easy to misread. 0.0049 baht per KB is about 5 baht per MB, or roughly 5,100 baht for a single gigabyte. A partial minute is charged as a full minute. This is why the one rule that matters is to buy a package before you cross.

The Lao networks AIS lists

AIS lists four roaming networks in Laos and marks voice calls, receiving calls, data roaming and SMS as available on all four.

Network	Names your phone may show	Signal AIS lists
Beeline	VimpelCom, Beeline	GSM 900/1800, 3G 2100, 4G 900/1800/2100/2300/2600
ETL	457 02, Lao 02, ETL MNW, ETL Mobile, ETL Network, ETL Mobile Network, 45702	GSM 900/1800, 3G 2100, 4G 2600
Lao Telecom	45701, LAO GSM, Lao Telecom	GSM 900/1800, 3G 2100, 4G 2600, 5G
Unitel	LATMOBILE, UNITEL, 45703, Unitel	GSM 900/1800, 4G 1800/2600, 5G, 4G VoLTE and HD Voice

The names in the middle column are what may appear in your phone’s network list, which helps if you ever need to choose a network manually. AIS adds that service performance depends on the network capacity of the roaming operator.

AIS and Lao Telecom: the souvenir promotion

Separately, AIS runs an “AIS x Lao Telecom” promotion for customers on Ready2Fly packages and SIM2Fly. The benefit is a souvenir from Lao Telecom, redeemed at its service centres in Vientiane, Luang Prabang and Champasak: dial *545*480*1# for a code by SMS and show it at the counter. The campaign runs from 8 July 2025 to 31 December 2026, with one redemption per number and 1,300 in total. It is a souvenir promotion, not a roaming agreement, but it does confirm that Ready2Fly is the package family AIS points Laos-bound travelers to.

What AIS travelers report

The clearest positive traveler reports on r/laos are for AIS. One user described an AIS roaming option of roughly 95 baht for about a week and 2GB and found the convenience worth it. AIS’s current Laos list starts at 169 baht for 3GB over 7 days, so that figure comes from an older or different offer, which shows how quickly these packages change. Another user said an AIS SIM had historically worked near the river but was unreliable away from it without roaming. Both reports are anecdotal.

What we could not verify for AIS

AIS’s page does not say what speed applies after a Ready2Fly allowance is used, whether prepaid and postpaid customers see different prices, or whether hotspot use is allowed, so we do not state any of those. It also shows no price for the SIM2Fly Asia options. Check the package screen in the AIS app before you buy.

Can DTAC work in Laos?

Yes. DTAC now shares its roaming service with True, and you buy the package in the True App.

True presents international roaming as one “True dtac” service. Its consumer roaming page says True and dtac customers can subscribe to roaming on the True App, with separate support numbers for each brand. Laos sits in True’s GO Travel “Neighboring” group, so a dtac number can buy the same style of package a True number buys, subject to the tariff and SIM type on your account. We could not confirm from a public page that every dtac tariff sees identical packages, so check your own account view in the app.

A traveler who regularly crosses from Thailand reported using a 99-baht dtac roaming package bought in the app. Treat that as an anecdote about one trip, not a price list.

Can True (TrueMove H) work in Laos?

Yes. True lists Laos in its GO Travel “Neighboring” group.

True GO Travel “Neighboring” packages

True’s published GO Travel schedule groups Cambodia, Laos and Malaysia together:

Package	Data	Validity	Price (before 7% VAT)	After the allowance
GO Travel Neighboring	3GB	7 days	149 baht	Speed throttled to 128 Kbps
GO Travel Neighboring	6GB	7 days	249 baht	Speed throttled to 128 Kbps

One caveat matters. The schedule we could read is the one for postpaid business customers, in effect from 16 September 2025 until further notice. Consumer prices and allowances in the True App may differ, so use these figures as a guide to the shape of the offer, not as your price.

A True user on r/laos said their data was enough for a trip to Vientiane without buying a Lao SIM. Other travelers mention inexpensive True bundles for Laos, and note that allowances change often.

How to set up Thai roaming for Laos

1. Buy the package before you cross. Use your operator’s app (AIS app, or the True App for True and dtac). Confirm the package lists Laos by name, then check the validity, the data allowance and the speed after the allowance runs out.
2. Confirm your line is eligible. Prepaid, postpaid and travel SIMs can see different offers. If Laos is missing from the app, contact your operator before you travel.
3. Cross the border, then turn on data roaming in your phone settings. Do this after buying the package, not before, so you never sit on default rates.
4. Let the phone register. It should attach to a Lao partner network within a minute or two. If it stays on a Thai network near the border, move a little away from the river and restart the phone.
5. If it fails, choose a network manually. In your network settings, turn off automatic selection and pick a listed Lao network, but only one your operator’s Laos agreement supports.
6. Check tethering before relying on it. Hotspot use is not guaranteed on roaming packages, and the terms we could read do not grant it explicitly. Read the package’s in-app terms before you plan to share data with a laptop.
7. Turn roaming off when you leave Laos, so you are not billed for it once you are back in Thailand.

How much does Thai roaming cost in Laos?

Published rates

What	Figure	Source and condition
AIS Ready2Fly Border, 3GB / 7 days	169 baht + VAT	AIS Laos roaming page
AIS Ready2Fly, 8GB / 10 days	449 baht + VAT	AIS Laos roaming page
AIS Ready2Fly, 15GB / 10 days	649 baht + VAT	AIS Laos roaming page
AIS Ready2Fly, 20GB / 15 days	849 baht + VAT	AIS Laos roaming page
AIS data, no package	0.0049 baht per KB (about 5 baht per MB)	AIS Laos roaming rates, excluding 7% VAT
True GO Travel Neighboring, 3GB / 7 days	149 baht + 7% VAT	True business schedule, postpaid business customers
True GO Travel Neighboring, 6GB / 7 days	249 baht + 7% VAT	True business schedule, postpaid business customers
After the True package allowance	Speed throttled to 128 Kbps	True GO Travel terms
True postpaid, roaming on, no package	350 or 499 baht per day (excluding VAT), depending on country	True consumer roaming page; includes non-stop data at full speed for a capped 1GB
True, where no specific country or network rate applies	450 baht per MB	True consumer roaming page

Compare like with like. For 3GB over 7 days, AIS Ready2Fly Border is 169 baht and True’s business schedule shows 149 baht, both before VAT. The True figure is a business-customer schedule, so check the True App for what you would actually pay.

Read the no-package rows carefully. AIS’s roughly 5 baht per MB adds up to about 5,100 baht for one gigabyte, and True’s 450 baht per MB is a worst case for destinations outside a specified arrangement, not the normal Laos rate. True’s postpaid fallback of 350 or 499 baht per day is what a customer pays for switching roaming on without a package.

Traveler-reported prices (unofficial)

These come from r/laos and are anecdotal. They are not current price lists and may not match what you see in the app today:

• A dtac user reported a 99-baht roaming package bought in the app.
• An AIS user reported roughly 95 baht for about a week and 2GB. AIS’s current Laos list starts higher (169 baht for 3GB over 7 days), so treat older figures with caution.
• True users mention cheap Laos bundles and say allowances change often.

The pattern is consistent: a short roaming package for a few days in Vientiane is inexpensive, and the surprise bill comes from roaming without one.

Will my Thai SIM work outside Vientiane?

It can, but the community view is that roaming suits short stays in Vientiane better than a long trip across Laos. Travelers who go to Luang Prabang, Vang Vieng, Pakse or rural areas, or who need reliable data for work, commonly recommend a local SIM or eSIM on Unitel or Lao Telecom instead. Reports describe Unitel as affordable and broadly reliable across the country. These are experiences, not a coverage guarantee, so check the coverage map of the network you plan to rely on.

The practical version: use roaming for a short Vientiane hop where you mostly need messaging, maps, ride-hailing and OTP codes, and switch to a local data plan as soon as your trip gets longer or leaves the capital.

Thai roaming or a Lao eSIM: which is better for your trip?

Choose by trip type

Your trip	Best option
A day or two in Vientiane, light use	Thai roaming package is usually enough
A week or more, or heavy data use	Compare the roaming package with a Lao eSIM
Luang Prabang, Vang Vieng, Pakse or rural areas	Lao eSIM on a local network
Remote work or video calls	Lao eSIM as your main data line
Keeping your Thai number for SMS and OTP	Keep the Thai SIM active alongside a Lao eSIM (dual SIM)

Roaming vs a Lao eSIM at a glance

	Thai roaming package	Lao eSIM (ours)
Setup	Buy in your Thai app before crossing, enable roaming	Install the eSIM by QR code before you fly, data starts when it connects
Network	A Lao partner network chosen by your operator’s agreement	Unitel directly
Data	A few GB for a week at the low end, with larger bundles costing much more	10GB to 30GB over 10 to 30 days
Your Thai number	Stays active	Stays active on your Thai SIM if your phone is dual-SIM
Calls and SMS	Some AIS packages bundle minutes and SMS; otherwise per your plan’s roaming terms	Not included: data-only
Hotspot	Not guaranteed, read the package terms	Supported on our plans
Best for	A short Vientiane visit	Longer stays, several cities, heavier use

Can I use a Lao eSIM with my Thai SIM?

Yes, on a dual-SIM phone. Keep your Thai SIM active for your Thai number and set the Lao eSIM as the mobile data line, so data goes through the eSIM while your Thai number stays reachable for messages and OTP codes. Make sure roaming is off on the Thai SIM’s data so it does not use roaming by accident. If you are not sure your phone supports eSIM, check whether Laos supports eSIM and follow our step-by-step activation guide.

Our Laos eSIM plans

If a local option is the right call, our Laos eSIM plans run on Unitel and activate automatically when they connect. Prices at the time of writing:

Plan	Data	Validity	Price
Laos eSIM	10GB	10 days	$6.90
Laos eSIM	15GB	15 days	$7.90
Laos eSIM	20GB	30 days	$8.90
Laos eSIM	30GB	30 days	$9.90

They are data-only: no Lao phone number, calls or SMS. For plan-by-plan Unitel details see our Unitel data package prices, and for how the Lao operators compare, see the best Laos SIM cards for tourists. If your route continues in Thailand, our Thailand SIM and eSIM guide covers AIS, DTAC and True on the Thai side.

Common problems and fixes

• No data after crossing. Check that the roaming package is active, data roaming is on, and the phone has registered on a Lao network. Restart the phone, then try selecting a Lao network manually.
• The phone stays on a Thai network near the border. Move away from the river, restart, or select a Lao network manually. A phone that clings to a distant Thai tower can drain the battery.
• Data works but is very slow. You may have used the package allowance and been throttled to 128 Kbps, or you are on a weaker partner network. Check the package usage in the app.
• A surprise bill. Roaming without a package is the usual cause. Buy a package first, and turn data roaming off when you are not using it.
• You need more data than the package gives. Add a Lao eSIM as your data line and keep the Thai SIM for your number.
• OTP or SMS codes do not arrive. Keep the Thai SIM active in a dual-SIM phone so messages to your Thai number still reach you. Check your operator’s terms for receiving SMS while roaming.

The bottom line

For a day trip or a few days in Vientiane, keep your Thai SIM, buy your operator’s Laos roaming package before you cross, and expect it to be adequate for messaging, maps, ride-hailing, banking codes and moderate browsing. Check the current package in the AIS app or the True App first, because allowances and prices change.

For a week or more, heavy data use, remote work, travel outside the capital, or time away from the Thai border, use a Lao eSIM or SIM as your main data line and keep the Thai SIM for your Thai number. That combination gives you local coverage and keeps your existing number reachable.

How we checked this

Last checked 26 September 2026. We separate what operators publish from what travelers report, and we say what we could not verify.

What the article relies on	Source	Date or status
True and dtac share one roaming service, subscribe in the True App, 350 or 499 baht per day fallback, 450 baht per MB rate	True and dtac international roaming	Read 26 September 2026
GO Travel Neighboring group (Cambodia, Laos, Malaysia), 149 baht for 3GB and 249 baht for 6GB over 7 days, 128 Kbps after the allowance, 7% VAT, postpaid business eligibility	True GO Travel terms	In effect from 16 September 2025 until further notice; read 26 September 2026
AIS Ready2Fly packages, pay-per-use rates and Lao roaming networks for Laos	AIS roaming rates and packages	Official AIS page for Laos, saved and read 26 September 2026; prices exclude 7% VAT and AIS may change them without notice
AIS x Lao Telecom souvenir promotion for Ready2Fly and SIM2Fly customers	AIS x Lao Telecom	Campaign 8 July 2025 to 31 December 2026; page text read on 26 September 2026. It describes a souvenir promotion, not a roaming agreement or a price
How to buy AIS roaming	AIS roaming	Operator page
Traveler experiences: border signal, roaming packs, coverage beyond Vientiane	r/laos: do you get phone reception with a Thai SIM card and r/laos: which mobile provider for 14 days	Anecdotal, not operator guarantees
Our Laos eSIM plans and prices	Our own catalog	26 September 2026

What we could not verify: True and dtac consumer package prices in the True App, whether every dtac and True tariff sees identical packages, the speed AIS applies after a Ready2Fly allowance is used, whether AIS prepaid and postpaid customers see different prices, AIS’s SIM2Fly Asia prices, and a written guarantee that tethering is allowed on any roaming package. We have left those out or labelled them rather than guess. Roaming packages and participating networks can change without notice, so confirm the current details with your operator before you travel.