How do I protect my phone?

A modern phone holds your email, which resets every other account you own. Physical security of the device matters, but the settings that limit what a thief can do with it matter more — and most of them take a minute each.

What you'll need

• Phone settings access
• Second device (optional)
• IMEI number recorded (optional)

Step by step

1. Set a strong screen lock — a six-digit PIN at minimum, ideally longer.Four digits is weak. Biometrics are convenient but the PIN is the fallback and is what a thief will target.
2. Turn off message previews on the lock screen.Two-factor codes arriving by SMS are visible on a locked phone otherwise, which defeats the point of them.
3. Enable Find My iPhone or Find My Device.It lets you locate, lock and erase the phone remotely. Check it is actually on rather than assuming.
4. Restrict what is accessible from the lock screen.Control centre, wallet and reply-from-notification can all be limited. On iPhone, Stolen Device Protection adds delays to sensitive changes away from known locations.
5. Make sure backups are running and verify the date.A stolen phone is only a device loss if the data is backed up. Otherwise it is a data loss too.
6. Record the IMEI number somewhere separate.Dial *#06# to display it. Networks and police need it to block or trace a handset.
7. If it is lost or stolen, mark it as lost immediately from another device.This locks it, displays a message and prevents it being wiped and reused. Do this first.
8. Then contact your network to block the SIM, and your bank if payment cards are stored.SIM blocking prevents calls and SMS two-factor interception. Speed matters for both.

Tips

• A phone case and screen protector cost far less than a screen repair, which is the most common phone damage by a wide margin.
• Avoid charging from unknown public USB ports. Use your own charger and a mains socket, or a data-blocking cable.
• Two-factor codes by authenticator app are safer than SMS, partly because they are not visible on a lock screen and cannot be intercepted by SIM swapping.

Common mistakes

• Leaving message previews on the lock screen — SMS two-factor codes become readable without unlocking the phone.
• Not checking that Find My is enabled — People assume it is on. If it is not, a lost phone cannot be located, locked or erased.
• Delaying marking a stolen phone as lost — The window in which a thief can act is short. Marking it lost immediately closes it.

Questions people ask