Begin with the one that costs nothing. LocalPay gives you 5GB in Vietnam plus a QR wallet spanning Vietnam, Indonesia and the Philippines — add a paid regional plan afterwards, and only for the legs it leaves open.

Navigation costs almost nothing. What quietly empties an allowance is the stuff travellers never think to account for — autoplaying video, an evening call home, a laptop on your hotspot.

Either one gets you online. What actually separates them is what you pay, whether you need a Vietnamese number, and which network you're riding on once the cities are behind you.

Whether you'd rather grab a SIM the moment you land or activate an eSIM before you even board, here's how to get online in Vietnam without overpaying or wasting time at arrivals.