DeviceIntermediate30 minall
Phone Number Hygiene
Risk
The risk
Why this matters
Your phone number is persistent, tied to real identity (SIM registration laws in EU), and used as recovery/2FA everywhere. SIM swap attacks exploit this. Phone numbers are more dangerous than email addresses as identifiers — and harder to change.
Setup guide
How to set it up
- 1
Audit: which services have your real phone number? Prioritize removing it
- 2
Remove phone number from accounts that don't strictly require it
- 3
Switch 2FA from SMS to TOTP wherever possible (see 2FA Hierarchy practice)
- 4
For services requiring a number: use a secondary VOIP number
- 5
Contact your carrier and add a SIM lock / port-out PIN