Contents
Short answer
A lost smartphone mainly becomes a problem when it is your password manager, authenticator, email, banking and recovery device all at once. Prepare: a secure device lock, the find feature if you want it, automatic backup and recovery codes that aren’t only stored on that device. If your phone is already gone, our incident help has the immediate steps.
Why one device can affect many logins
The smartphone as a key ring
Often the same device receives SMS codes, generates authenticator codes, holds the password manager, email inbox and banking app and is registered as the trusted device for recovery. If it’s gone, several routes are blocked at once – in the worst case including the route to recover the others.
What follows
Plan at least one second route to your most important accounts that doesn’t depend on the phone: for example a second registered passkey or security key, printed recovery codes or a second trusted device.
Step by step
- 01
Set a secure device lock
Use a PIN or password rather than a simple pattern. Fingerprint or face unlock is convenient and protects day to day, but doesn’t replace the good code behind it – you need that after a restart, for example.
- 02
Turn on the find feature if you want it
The operating system’s find feature lets you locate, lock and mark the device as lost. Whether you use it is a trade-off with your privacy.
- 03
Switch on automatic backup
Back up photos, contacts and settings regularly so a replacement can be set up quickly. Check now and then when the last backup ran.
- 04
Keep recovery codes separately
Don’t store recovery codes for important accounts only on the same phone. A printout in a safe place or a second device are possible options.
- 05
Know your important accounts
Note which accounts really matter: email, Apple or Google account, banking, messengers, password manager. For each, check how you’d get in without this phone.
- 06
Know your SIM, eSIM and mobile provider
Know how to reach your provider and how to request a block or replacement SIM or eSIM. Keep your customer number somewhere other than the phone.
- 07
Consider banking and authenticator dependencies
Find out how your bank activates a new banking or TAN app. Check whether your authenticator supports transfer or backup – and set up a second route for important accounts as well.
If it has happened: in short
Locate and lock
Lock the device via the find feature and mark it as lost. The detailed immediate steps are in our incident help.
Secure mobile access
Have the SIM or eSIM blocked by your provider so nobody can receive SMS codes.
Check important accounts
From another device, change passwords of important accounts if the phone wasn’t securely locked, and remove the lost device in your account settings.
Inform your bank if needed
If there’s a risk someone could use banking apps, block access via your bank.
Remote wipe with care
A remote wipe can make sense, for example if sensitive data isn’t sufficiently protected. Consider first: afterwards, locating is usually no longer possible, and a police report or recovery may become harder. Weigh it up rather than wiping by reflex.
Checklist
- Device lock with PIN or password is active.
- Find feature is set up if I want to use it.
- Automatic backup is running and current.
- Recovery codes aren’t only stored on this phone.
- Important accounts have a second sign-in route without this device.
- I know how to reach my mobile provider and bank.
Common mistakes
- Saving all recovery codes as screenshots on the same phone.
- Relying only on SMS codes that stop arriving after a loss.
- Treating biometrics as enough and using a weak code behind it.
- Wiping the lost device straight away even though it could still be located.
- Only finding out after the loss how the bank activates a new app.
Frequently asked questions
What happens to my authenticator codes if my phone is gone?
If they’re only on that device and there’s no backup, you can’t retrieve them. You’ll then need recovery codes or the service’s recovery route. That’s why a second route set up in advance is worth it.
Should I wipe my lost phone straight away?
Not automatically. Lock it and mark it as lost first. Wiping can make sense but usually stops further locating. Consider whether you still want to find the device.
Is fingerprint or face unlock enough?
Biometrics are a convenient extra. A good code still matters, as it’s requested after a restart, for example.
Do I have to turn on the find feature?
No. It helps find and lock the device but shares location data with the provider. Decide consciously.
Where should I keep recovery codes?
Somewhere that doesn’t depend on the phone – for example printed in a safe place at home, or in a password manager you can also open on another device.
Sources
- BSI – Smartphone und Tablet effektiv schützen
- BSI – Cyber-Sicherheit²: Was tun beim Verlust des Smartphones? (Video)
- BSI – Vergleich gängiger 2FA-Verfahren
Checked on 7 October 2026.