Roaming or an eSIM in Vietnam: what changes
Roaming keeps your home line working in Vietnam at your carrier's rates. A prepaid eSIM gives you a separate data line at a fixed price.
- Prepaid, fixed price
- Data roaming only if needed
- Home line stays on
The short answer
Roaming on your home line charges your carrier's rates in Vietnam. The eSIM from this site is prepaid: you pay once, it runs on a Vietnamese network, and it cannot add charges. Data roaming stays off on both lines; switch it on for the eSIM line only if the line does not connect.
Checked October 2, 2026
Home roaming against an eSIM
Price
- Roaming on your home line
- Your carrier's roaming rates
- eSIM from this site
- One prepaid price, tax included
Extra charges
- Roaming on your home line
- Possible, depending on your carrier
- eSIM from this site
- None: the plan is prepaid
Setup
- Roaming on your home line
- Nothing to install
- eSIM from this site
- Set up at home; switch on once you land
Data roaming switch
- Roaming on your home line
- Keep it off
- eSIM from this site
- Off by default; on for that line only if it will not connect
Your number
- Roaming on your home line
- Your own, at your carrier's rates
- eSIM from this site
- Your own stays on; some plans add a Vietnamese number
Which switch goes where
For the eSIM line: switch it on and hand it the mobile data job. Data roaming stays off here, except for that line when it will not connect; the store gives that guidance itself. On the home line, data roaming stays off so no charges can pile up, and the line can stay on if you want calls and texts to arrive. Anything arriving at your home number, call or text, comes on your home carrier’s bill.
The plan for this trip
15 days · 5 GB a day · US$8.88
Tax included. The plan names its Vietnamese network, and whether it has calls or a number, before you pay.
Buy on VietSIMQuestions
Do I need a shop for the eSIM?
No. The eSIM is bought online before you fly: the QR code is on your order page right after payment, and you install it at home. A SIM card bought in Vietnam is registered at the point of sale, and the shop asks for your passport.
At what point does the eSIM line need data roaming?
Only if the line does not connect. These plans run on Vietnamese networks, so the switch normally stays off; the store names it as the fix for a line that will not start, and a prepaid plan cannot add a charge because of it.
Sources
Where the facts on this page come from.
Get your Vietnam eSIM before you fly.
Plans from US$5.88, tax included, on Vietnam’s own networks. Pick one here and pay on the store in US dollars.
See the plansCheckout on VietSIM · full refund if it does not work