The best eSIMs for international travel

Our guide will help you get up to speed on what an eSIM is, compare three of the best eSIM providers and understand the limitations of this powerful technology.

The basics of eSIMs

A SIM (subscriber identity module) is a microchip that authenticates a phone number. When you slot a SIM card into your smartphone or tablet, it lets you make calls, send texts and use data over a 4G or 5G network. 

Savvy globetrotters avoid roaming costs on their phones by buying a local SIM card in each country they visit. But that requires hunting out a local store and buying the right little square of plastic to replace your New Zealand SIM. 

These days, you can usually save even more while travelling by buying embedded SIMs (eSIMs) instead.

While an analogue SIM card is tied to a particular mobile provider, an eSIM chip lets you install several eSIM profiles, each with its own phone number, that might work with any number of networks around the world. These chips are built into newer devices. 

You can also save precious holiday time by buying and setting up your eSIM before you even board your plane. 

Choosing an eSIM provider and plan 

First, think about how much data you’ll need. Check your usage history on your mobile provider’s website or app to get a baseline average, then adjust it based on how often you expect to be out of WiFi range on your trip. 

Some providers offer calling minutes and texts as part of their eSIM packages, while other packages are data only (and usually cheaper). 

Some eSIM packages can only be used in one country, while others cover a continent or even the entire planet. If you’re globetrotting, it might be worth finding a package that covers your whole holiday rather than buying a new eSIM for each stop. 

We bought eSIMs from three sellers – Airalo, Saily and Instabridge – and assessed each for their ease of installation and using the app and value for money. 

Unfortunately, we didn’t have the budget to fly a researcher to Australia, so we couldn’t test the network performance of each, but thankfully, we haven’t heard many horror stories about eSIM performance. 

Setting up your eSIM 

When you buy an eSIM, you’ll receive detailed instructions on how to install it – follow them as closely as you can.  

Downloading your eSIM provider’s app will make it easier to install the eSIM, but if you don’t want to or can’t do that, there are alternative methods that involve manually entering alphanumeric keys or scanning QR codes. It generally takes 5 to 10 minutes to install an eSIM but try to set aside half an hour in case you need to do some troubleshooting.  

Most eSIMs activate when you first touch down in your destination country. Watch out for those that activate upon installation – you’ll need to wait to install them until you’ve arrived (or are en route).

The downsides of eSIMs 

Compatibility  

Not every device has an eSIM chip, so you’ll need to make sure your device is compatible before you buy an eSIM.  

To check your device’s compatibility, dial *#06# on the device. This will bring up the device’s identification codes. Your phone is eSIM compatible if the codes include a number labelled ‘EID’ (not to be confused with ‘MEID’, which is an unrelated ID number). 

Every iPhone since the 2018 XS/XR series has eSIM capability. Android phones vary by brand and model. 

You’ll also need to make sure your phone isn’t locked to a particular network, which is sometimes the case for very cheap phones or ones bought on contract. You can almost always contact your provider to get a phone unlocked, but it might cost you. 

Switching off your regular SIM 

Perhaps the biggest practical barrier to using an eSIM overseas is two-factor authentication over SMS. If your bank sends you text messages to verify large purchases, for example, those texts will go to your regular SIM, and if you’ve switched it off to save money, you won’t receive the text. 

Plan how you will get around this before you leave – you can often set up alternative two-factor authentication methods. 

You also won’t receive other calls or texts to your New Zealand number. You can always turn on roaming occasionally to catch up on anything you might have missed or if you’re expecting an important call at a certain time. Otherwise, you can ask people to contact you using a web-based service, such as WhatsApp. 

Are physical SIMs on the way out? 

eSIMs are expected to completely replace physical SIMs at some stage – but nobody knows exactly when. 

According to eSIM provider Airalo, the primary barriers to complete adoption are infrastructure readiness in some regions and consumer familiarity with the eSIM technology. 

In the States, Apple iPhones haven’t been sold with physical SIM card slots since the 2022 iPhone 14. Outside the States, manufacturers have been much more cautious about committing to eSIMs. 

Many eSIM providers are primarily focused on overseas connectivity rather than everyday domestic use. A spokesperson from Airalo said that could change soon.  

“As the technology continues to evolve, we anticipate expanding local service offerings to provide consumers with more comprehensive domestic connectivity options.” 

Here at home, many domestic customers are eschewing their old plastic cards in favour of a digital future. New Zealand mobile providers took a while to embrace eSIMs, but they seem to be fully onboard now. 

“It’s easy to switch from a physical SIM to an eSIM,” said Quentin Reade, head of communications at 2degrees. “People can pop into their local 2degrees store, and we will help them set up an eSIM.”