Guide · 4 min read
Why you should not give your real phone number to every app
How your personal phone number leaks, why that matters (spam, SIM-swap, tracking), and simple ways to keep it private when an app insists on SMS verification.
Updated
Your number is an identifier
A phone number follows you for years and links your accounts together. Every app that stores it is one more place it can leak from, be sold, or be matched with your other data.
What can go wrong
- Spam calls and texts after a shop or app shares or loses its customer list.
- SIM-swap attacks: a criminal who knows your number and some personal details persuades your carrier to move it, then receives your security codes.
- Profiling: the same number across many services lets them be linked to one person.
Simple habits that help
Keep your personal number for your bank, your carrier and the people you know. For one-off sign-ups, newsletters, marketplaces and trial accounts, use a separate number — a one-time virtual number works for most of them. Turn on app-based two-factor sign-in wherever it is offered, rather than SMS codes.