Is Signal Safe? Security Review
5/5
Overall Safety Score
★
★
★
★
★
Verdict: Signal is the most secure mainstream messaging app available. It collects virtually no user data, uses best-in-class encryption, and is operated by a non-profit foundation with no advertising business model.
Signal is a non-profit encrypted messaging app widely considered the gold standard for private communication. Its Signal Protocol powers encryption in WhatsApp, Google Messages, and Facebook Messenger.
Security Ratings Breakdown
| Category | Score | Rating |
|---|---|---|
| Encryption | 5/5 | |
| Privacy | 5/5 | |
| Track Record | 5/5 |
Security Features
- End-to-end encryption for all messages, calls, and video calls
- Signal Protocol (open-source, independently audited)
- Sealed sender to protect metadata
- Disappearing messages
- Screen security (blocks screenshots)
- Registration Lock (PIN protection)
- No ads, no tracking, non-profit
Privacy Concerns
- Requires a phone number for registration (though username support was added)
- Centralized server infrastructure (not federated)
- Contact discovery requires sharing phone number hashes
Past Security Incidents
- 2022 Twilio breach exposed phone numbers of approximately 1,900 Signal users (Signal's encryption prevented message exposure)
- Signal's response demonstrated its minimal data retention: it could only confirm registration status and last connection date
How to Stay Safe Using Signal
- Set up a Registration Lock PIN
- Enable disappearing messages for sensitive conversations
- Set a Signal PIN for account recovery
- Use a username instead of sharing your phone number
- Verify safety numbers with important contacts
Safer Alternatives
- Session (no phone number required, decentralized)
- Element/Matrix (federated, encrypted)
Last updated: February 10, 2026