The border trap, priced
One eSIM for Vietnam and Cambodia
A Vietnam-only plan stops dead at Moc Bai. Here is what a regional plan actually costs against buying two local ones, and the crossover point where each wins.
What actually happens at Moc Bai the failure this page prevents
A Vietnam eSIM is a Vietnam eSIM. Cross into Cambodia at Moc Bai or Bavet and it stops working, immediately and completely, with no roaming fallback and no warning screen.
That matters more at a land border than it would at an airport. You arrive at a crossing point with money changers, a visa-on-arrival window, onward bus touts and no wifi. This is the moment you most want a working phone, and it is the exact moment a single-country plan dies.
The same applies at Bavet going the other way, at the Laos crossings in the north, and on the Ha Tien to Kep route in the south. Anywhere the trip involves a land border, buy the coverage before you reach it.
Regional plan or two local ones? the numbers, not the received wisdom
Costa Rica taught us not to assume regional plans cost more; there, Airalo's regional plan was cheaper than its own local one below 10GB. In Southeast Asia the received wisdom holds, but the premium is smaller than people expect.
| Size | Airalo Asialink (both countries) | Airalo Vietnam only | Airalo Cambodia only | Regional premium |
|---|---|---|---|---|
| 1GB / 3 days | $4.00 | $4.00 | $4.00 | none |
| 5GB / 30 days | $15.00 | $11.00 | $13.00 | +$4 vs Vietnam |
| 10GB / 30 days | $25.00 | $18.00 | $21.00 | +$7 vs Vietnam |
| 20GB / 30 days | $39.00 | $29.00 | $32.00 | +$10 vs Vietnam |
| 50GB / 30 days | $59.00 | $49.00 | $49.00 | +$10 vs Vietnam |
| Unlimited / 30 days | $73.50 | $69.00 | — | +$4.50 vs Vietnam |
Airalo sells Vietnam as Xin Chao, Cambodia as Connect Cambodia and the regional plan as Asialink. All three are the same account and the same app. Prices in USD before promo codes, checked September 4, 2026.
Now put it the way you would actually spend it. Say a two-week trip, ten days in Vietnam and four in Cambodia, and about 10GB of data across the whole thing.
| Approach | What you buy | Total | The catch |
|---|---|---|---|
| One regional plan | Asialink 10GB / 30 days | $25.00 | None worth naming. One profile, one install, use the data wherever it lands. |
| Two local plans, split 5/5 | Xin Chao 5GB + Connect Cambodia 5GB | $24.00 | Saves a dollar and locks the split in advance. Run out in Vietnam with 3GB unused in Cambodia and you have lost the dollar four times over. |
| Two local plans, split 10/3 | Xin Chao 10GB + Connect Cambodia 3GB | $27.00 | Costs more than the regional plan and still cannot move data across the border. |
So the honest answer for two countries is the regional plan, and the reason is not the headline price, which is close to a tie. It is that a regional plan lets you be wrong about the split.
Where local wins outright: a trip that is overwhelmingly one country, with a two-day side trip. Ten days in Vietnam and one afternoon in Cambodia does not justify a $7 premium on the whole allowance. Buy Vietnam, buy a $4 Cambodia 1GB for the day trip, done.
Asialink is the plan to buy for a two-country trip. It is sold from the same Airalo checkout as the Vietnam plan, so pick the regional tab rather than the country one before paying.
See Airalo Asialink plans Compare all six providersDo not buy the regional plan from the wrong brand the $11 mistake
| 10GB, 30 days, covers Vietnam + Cambodia | Price | Verdict |
|---|---|---|
| Airalo Asialink | $25.00 | The buy. $7 over the Vietnam-only plan, and it covers Laos and Thailand too. |
| Saily Asia and Oceania | $35.99 | Double Saily's own Vietnam price of $17.99. Whatever the regional plan is for, it is not this trip. |
| Two Airalo local plans (5+5) | $24.00 | A dollar cheaper and you have to guess the split correctly. |
| Airalo Vietnam only | $18.00 | Stops working at the border. Listed so the comparison is honest, not as an option. |
Saily's regional pricing is out of line with its own local pricing in this region, which is worth knowing because Saily is otherwise the brand with the best support record in our main comparison. GigSky, Yesim and Holafly do not sell a regional plan that makes sense for this pair. Checked September 4, 2026.
Adding Thailand or Laos where the regional plan starts paying for itself
The $7 premium buys coverage across Asialink's whole footprint, not just the two countries you were thinking about. On a two-country trip that is a small overpayment for flexibility. On a three or four country trip it stops being a premium at all.
The classic Southeast Asia loop, Thailand into Cambodia into Vietnam, on local plans: roughly $18 for Vietnam, $21 for Cambodia and a Thai plan on top, three profiles, three installs, three chances to be holding the wrong one at a border. On Asialink it is one purchase at $25 for 10GB, or $39 for 20GB.
If you are out for longer, Asialink's 50GB for $59 over 30 days or 100GB for $89 over 180 days are the two plans on this site with the lowest cost per gigabyte of anything we list, at $1.18 and $0.89 respectively. The 180-day validity is genuinely unusual and it is the right buy for a season of travel rather than a holiday.
Questions on crossing the border
Which eSIM is best for travelling to Vietnam and Cambodia?
Airalo's Asialink regional plan, at $25.00 for 10GB over 30 days. It works on both sides of the border on one profile and also covers Laos and Thailand. Buying Airalo's two local plans instead costs about the same and forces you to guess how much data you will use in each country.
Will my Vietnam eSIM work in Cambodia?
No. A single-country plan covers that country only and stops at the border with no roaming fallback. At a land crossing like Moc Bai or Bavet that means arriving with no data at exactly the point where you want a map, a currency rate and a bus booking.
Is a regional eSIM more expensive than a local one?
In Southeast Asia, yes, by about $7 at the 10GB size: $25.00 for Asialink against $18.00 for Airalo's Vietnam plan. That is not a universal rule, though. In Latin America Airalo's regional plan is actually cheaper than its own Costa Rica plan below 10GB. Always price the brand's regional plan against its local one rather than assuming.
What about Thailand and Vietnam on one eSIM?
Same answer: Asialink covers both. The premium over a Vietnam-only plan is fixed at around $7 for 10GB regardless of how many countries you actually visit, so the more borders you cross the better the regional plan looks. Check the covered-country list on the product page against your itinerary before paying.
Can I just install two eSIMs, one per country?
Yes, and on any phone that holds multiple profiles this works fine; you switch which line carries data in settings. It is the right move when one country dominates the trip and the other is a two-day side trip. It is the wrong move when the split is genuinely uncertain, because unused data does not cross the border either.
What is the cheapest way to cover a long Southeast Asia trip?
Airalo's Asialink 100GB over 180 days at $89.00, which works out at 89 cents a gigabyte with an unusually long validity window. For a shorter but still multi-country trip, Asialink 50GB for $59.00 over 30 days is $1.18 a gigabyte. Both beat any single-country plan on this site on cost per gigabyte.
One profile, both sides of the border
Asialink covers Vietnam, Cambodia, Laos and Thailand on one eSIM: 10GB for $25.00 over 30 days, or 100GB for $89.00 over 180 days if you are out for a season. Pick the regional tab, not the country one.
See Airalo Asialink plansSources & freshness: Airalo Asialink, Xin Chao (Vietnam) and Connect Cambodia prices via esimdb.com and airalo.com, September 4, 2026, in USD before promo codes. Saily Asia and Oceania regional pricing from the same source on the same date. Covered-country lists must be checked on the brand's own product page at purchase; they change. Compare the single-country options: best eSIM for Vietnam.