Travel eSIM or a local SIM: which do I need?

Short answer: if you want internet, a travel eSIM is enough. If you specifically need a phone number in the destination, for calls or texts on a local number, that is what a local SIM is for.

Most travellers only need the first.

First, a word that gets muddled

An eSIM is not a type of plan. It is a SIM in digital form, downloaded to your phone instead of slotted in. A travel plan and a local carrier plan can both come as an eSIM.

So "eSIM" and "travel eSIM" are not the same thing, even though they are often used as if they were. More in What is an eSIM?

Travel eSIM (this is Atli)

• Data only. No phone number, no carrier calls or texts.
• Prepaid, no contract, nothing to cancel.
• Installed before you fly, on wifi, so you land connected.
• One eSIM holds every plan you buy later, including for other destinations.

Apps that work over the internet, which is most of them, work normally: WhatsApp, iMessage, Telegram, FaceTime, maps, email.

Local SIM or local eSIM

• Usually includes a local phone number, and often calls and texts.
• Can be cheaper per gigabyte, particularly for a long stay.
• May require ID or registration in person, depending on the destination.
• Often sold as a monthly plan rather than a short trip.

Getting one does not switch off your own SIM. Both lines can be active on a phone that supports it.

Which one, for what

• Data for a trip: travel eSIM.
• Several destinations in one trip: travel eSIM, on a regional or global plan, or several plans on the same eSIM.
• A local number people can ring: local SIM. A delivery driver, a restaurant booking, a rental agency.
• Staying for months: worth pricing a local plan against a travel one.
• Keeping your own number reachable: neither. Keep your own SIM on with Data Roaming off. See Can I use a travel eSIM with my own SIM?

Do you actually need a local number?

Usually not. In most of the world people reach each other through messaging apps, and businesses answer there too. International calls and texts are expensive at both ends, so a foreign number is often the harder way to be contacted, not the easier one.

The common exception is something local and practical: a courier who will phone you, or a booking that wants a number in the country.