Several Southeast Asian countries, one phone: planning your data

From Tokyo, Seoul, Taipei or Hong Kong, Southeast Asia is close enough that one trip often becomes three countries: a few days in Bangkok, a flight to Hanoi or Ho Chi Minh City, then Kuala Lumpur or Singapore on the way home. Each border means a new set of mobile networks. Here is how to choose your data so the border days stay simple.

One regional eSIM, or one per country

A regional eSIM covers a list of countries with a single plan. You install it once at home, and it picks up a local network in each covered country as you arrive. It suits trips with several stops, quick hops and overland crossings, because there is nothing to switch.

One eSIM per country gives each stop its own plan. It suits trips that spend most of their time in one country with a short side trip, or travelers who want different amounts of data in different places. Most recent phones can store several eSIMs, so you can install them all at home and move mobile data from one to the next as you go.

Before you buy a regional plan, open its page and read the list of covered countries. Do not assume a country is included because its neighbours are. And count your days from the first connection to the last day of the trip, then compare that with the plan's validity.

You can compare both kinds side by side in the catalog.

Apps worth setting up at home

Grab is the ride hailing and food app across much of the region, including Singapore, Malaysia, Thailand, Vietnam, Indonesia and the Philippines. Sign up at home with your own number: the sign up code arrives by text, and that is far easier on your sofa than at a taxi rank.

Download offline maps for each city in Google Maps, and save hotel addresses in the local script as screenshots, so a driver can read them even if your data is slow for a minute.

Border days

Whether you fly or cross by land, the routine is the same. On arrival, give the phone a minute to find a local network. With one regional eSIM there is nothing to do. With one eSIM per country, open settings and move mobile data to the new line, and make sure data roaming is on for it. If nothing connects after a minute, switch airplane mode on and off once.

Keep your home SIM on for texts, with data roaming off, so bank and app codes still reach you.

Questions travelers ask

Is a regional eSIM better than buying one per country?

It is simpler for trips with several stops, because nothing changes at the border. One eSIM per country fits better when most of the trip is in one place.

How do I know which countries a regional plan covers?

Each regional plan page lists the countries it covers. Check that list before you buy.

Can I install several country eSIMs before I leave?

Yes. Most recent phones can store several eSIMs. Install them all at home and switch mobile data when you cross each border.

Do I need a local number for Grab?

No. You can sign up with your home number before you travel and use Grab over your eSIM data.