Tips for securing Signal with registration lock (PIN)
Applies to: Signal Messenger (Android, iOS)
Last updated: September 2025
Problem
Without extra protection, someone who gains access to your SIM card or phone number could try to re-register your Signal account on another device. This could compromise your private messages and contacts.
Solution
Signal provides a Registration Lock PIN (Signal PIN) that prevents re-registration of your account without your personal PIN. Enabling this adds a strong extra layer of security.
Step-by-step Instructions
Step 1: Enable Registration Lock
- Open Signal.
- Go to Settings > Privacy > Signal PIN.
- Set a PIN (at least 4 digits, but you can use alphanumeric for more security).
- Confirm the PIN.
- Toggle Registration Lock ON.
Step 2: Manage your PIN
- To change your PIN:
- Settings > Privacy > Change PIN.
- To disable PIN reminders:
- Adjust reminder frequency or turn them off.
Step 3: Enable additional security
- In Settings > Privacy, you can also:
- Enable Screen Lock (using fingerprint, Face ID, or passcode).
- Hide sensitive notifications (no sender or message preview).
Optional Methods or Tools
- Use a password manager to securely store your PIN.
- Combine PIN security with device-level security (lock screen, biometrics).
Best Practices / Tips
- Always set a recovery method (Signal will sometimes ask for your PIN).
- Avoid using simple PINs like “1234” or your birth year.
- Never share your PIN with anyone — Signal staff will never ask for it.
- Review active sessions under Settings > Linked Devices and unlink any suspicious devices.
