5GB a Day in Vietnam: Total Data, Cost per GB, and What Happens at the Cap
Most Vietnam eSIM listings quote a daily number — 5GB a day, 7GB a day — and leave you to work out what that means for a two-week trip. This page does the arithmetic, states exactly what happens when you hit the daily cap, and lists the cost per GB for every daily-cap plan we sell, so you can compare it against anything else you are looking at.
What 5GB a day adds up to
A daily allowance multiplied by the number of days is the total data you get. A Viettel 5GB/day plan for 7 days is 35GB. The same plan for 30 days is 150GB. A Skyfi 7GB/day plan for 15 days is 105GB.
Those totals are larger than most travellers expect, which is why a daily cap rarely becomes the thing that limits a trip. The number that actually differs between sellers is the price you pay for each of those gigabytes.
At the daily cap the data stops — it is not slowed down
On our daily-cap plans the full daily allowance runs at normal 4G/5G speed, and when the allowance for that day is used the data stops. It is not reduced to a slower speed.
The allowance resets at 00:00 Vietnam time (GMT+7), and from that moment the next day's allowance runs at full speed again. If you land in the evening and use the day's data in a few hours, you wait until local midnight rather than browsing at a crawl.
This matters because the two behaviours feel completely different on the ground. A plan that slows you down leaves maps and messaging technically working but painful. A plan that stops is clear about where you stand, and the reset time is a fixed, predictable hour.
Cost per GB is the number that decides
Here is the cost per gigabyte for every daily-cap plan we currently sell, taken from the same price list the checkout uses. Viettel 5GB/day: 7 days 9.90 USD for 35GB, which is 0.28 USD per GB; 15 days 12.90 USD for 75GB, 0.17 USD per GB; 30 days 18.90 USD for 150GB, 0.13 USD per GB.
Skyfi 7GB/day, which runs on the Mobifone network: 7 days 8.00 USD for 49GB, 0.16 USD per GB; 10 days 10.00 USD for 70GB, 0.14 USD per GB; 15 days 11.00 USD for 105GB, 0.105 USD per GB. The 15-day Skyfi plan is the lowest cost per GB in our catalogue.
Vinaphone costs about one dollar more than Viettel at the same length, and the reason is the number: Vinaphone is the only one of the three that comes with a Vietnamese number, which receives incoming calls and ordinary SMS but not verification codes from apps or banks.
Longer plans are cheaper per GB than short ones, so for a stay of 15 days or more a single longer plan costs less than two shorter ones.
What to ask before buying any unlimited Vietnam eSIM
Unlimited is not a standardised word in this market, so the useful thing is to ask the seller three specific questions before paying.
First: is there a daily threshold, and what happens when I pass it — does the data stop, or does the speed drop? Second: if the speed drops, to what speed, and for how long? Third: is tethering or hotspot sharing included, or is it restricted on this plan?
A seller who can answer all three in numbers is telling you what you are buying. If the answer to the second question is missing, the plan is unlimited in the sense that it never runs out, not in the sense that it stays fast.
What these plans do not do
Tourist plans cannot be topped up and cannot be extended. When the days are used the eSIM switches off, and more days means buying another plan, which starts its own validity period.
Viettel and Skyfi plans are data-only. Only the Vinaphone plans come with a Vietnamese number, and that number receives incoming calls and ordinary SMS — a Grab driver or a hotel can reach you. Verification codes from apps and banks do not arrive on it, and no plan makes outgoing calls or sends outgoing SMS.
For calls, use WhatsApp, Telegram or Zalo over the data you already have. If you genuinely need to dial a Vietnamese landline, buy a name-registered SIM in person at a shop in Vietnam.
FAQ
Is 5GB a day enough for a trip to Vietnam?
A 5GB daily allowance is 35GB across a week and 150GB across a month, which is more total data than most travel plans sold for the same price. Whether it is enough depends on how much video you stream, so if you expect heavy use the 7GB/day Skyfi plans give you more headroom for less money per GB.
What happens when I use all 5GB in one day?
On our daily-cap plans the data stops for the rest of that day and resets at 00:00 Vietnam time (GMT+7). The speed is not reduced; the allowance simply ends and then starts again at full speed after local midnight.
Do these Vietnam eSIM plans slow down after a daily limit?
No. The whole daily allowance runs at normal 4G/5G speed and then stops until midnight Vietnam time. There is no reduced-speed tier on our daily-cap plans.
Which Vietnam eSIM has the lowest cost per GB?
The 15-day Skyfi plan at 11.00 USD for 7GB a day works out to 0.105 USD per GB, which is the lowest in our catalogue. Longer plans are always cheaper per GB than shorter ones.
Can I add more data if I run out before my trip ends?
Tourist plans cannot be topped up or extended. If you need more days you buy another plan, and the new plan starts its own validity period rather than adding days to the old one.
Do I get a Vietnamese phone number with a 5GB a day plan?
Only the Vinaphone plans include a Vietnamese number. That number receives incoming calls and ordinary SMS, so a driver or a hotel can reach you, but verification codes from apps and banks do not arrive on it and it cannot make outgoing calls. Viettel and Skyfi plans are data-only.