Keeping your phone and data safe overseas

Your phone holds your boarding passes, bookings, banking and photos, so it is worth protecting on a trip as carefully as your passport. This checklist summarises the Australian Government's Smartraveller advice on cyber security when travelling overseas, and adds what changes when your data comes from a travel eSIM.

Short answer

Back up and update your phone before you leave, avoid sensitive tasks on public Wi-Fi, use your own charger and cable, and keep Wi-Fi and Bluetooth off when you are not using them. Smartraveller says a mobile network is often more secure than public Wi-Fi, which is one practical reason to have your own mobile data overseas.

Before you leave Australia

• Take only what you need. Smartraveller says the best protection for a device is to leave it at home if you do not need it.
• Back up your phone and leave the backup at home. If the phone is lost, stolen or compromised, the backup is how you get your photos and data back.
• Install updates for the operating system and browser before you go, and use the security protection your phone offers.
• Turn off auto-connect for Wi-Fi and Bluetooth, so the phone does not join networks by itself.
• Install your travel eSIM at home on your own Wi-Fi rather than hunting for a network on arrival. See the installation guide.

While you are away

• Be careful on public Wi-Fi. Smartraveller says not to expect privacy on public Wi-Fi, hotel Wi-Fi or in internet cafes, and not to send sensitive information on unsecured connections. Do banking and other sensitive tasks over mobile data instead.
• Keep connections off when not in use. Smartraveller suggests turning Bluetooth, Wi-Fi and other connections on only when you are using them.
• Charge with your own plug and cable or a battery pack. Smartraveller advises against shared USB charging stations and free USB cables or drives.
• Do not lend your phone to people you do not trust.
• Do not post your passport, boarding pass or tickets, and think twice before sharing your location or accommodation while you are still there.
• Consider a VPN. Smartraveller suggests considering one on devices that access the internet. If your travel eSIM will not connect with a VPN on, turn the VPN off for a moment while the phone connects, as the troubleshooting checklist explains.

Keep your eSIM details private

A travel eSIM's QR code and activation code are what install it, so treat them like a password: do not post them, and do not send them to anyone who asks, including someone claiming to be support. When you contact Telroo, send your order number, destination and phone model only. Keep the delivery email so you can find your order again.

If you think your phone has been compromised

Smartraveller lists warning signs such as apps crashing repeatedly, new pop-ups and ads, unexplained data or battery use, and suspicious activity in your accounts. Its suggested steps include:

1. Switch the phone to aeroplane mode so it stops sending data.
2. Run your security software.
3. Change your passphrases and sign out of active sessions on your accounts.
4. If you are still worried, get advice from a trusted service centre for your phone's brand, or factory reset and restore from your backup.

Before a factory reset, check what happens to your eSIMs. Apple says that when you erase an iPhone you can choose to keep or erase its eSIM. If you erase a travel eSIM by mistake, contact us with your order number rather than scanning the old QR code again.

A lost or stolen phone

Ask your Australian carrier how to block your Australian SIM, change the passwords for your important accounts, and keep a copy of your Telroo order number somewhere other than the phone, such as in an email you can open from another device. For help overseas, start from Smartraveller.

Travel phone security questions

Is mobile data safer than hotel Wi-Fi?

Smartraveller says your mobile network is often more secure than public Wi-Fi, and that you should not expect privacy on hotel Wi-Fi. Use mobile data for banking and other sensitive tasks.

Should I use airport USB charging points?

Smartraveller advises using your own plug and cable, or a charged battery pack, instead of shared USB charging stations.

Can someone else use my travel eSIM QR code?

Treat it as if they could. The QR code is what installs the eSIM, and Telroo's terms note that QR codes may be unique with limited reuse, so if someone else scans it you may not be able to install it yourself. Keep it private.

Sources and last checked

Checked 16 October 2026: Smartraveller, cyber security when travelling overseas (page last updated 18 August 2026); Apple, how to erase the eSIM on your iPhone or iPad. For more step-by-step guides, Smartraveller points to the Australian Cyber Security Centre at cyber.gov.au.