Is Signal encrypted?
Yes. Only you and the people you message can read your Signal chats and hear your calls, every time. Backups are optional and sealed with a key only you hold.
Checked on 25 October 2026 against 7 sources.
Made by Secria. We grade every app by the same rules. How we check
- MessagesOnly you and the people you messageAlways on: Signal has no unsealed mode.1
- Group chatsOnly you and the groupSignal says every message is end-to-end encrypted, every time, group chats included.1
- CallsOnly you and the people you callSignal says every call is sealed, every time.1
- BackupsOnly youBackups are optional, and when you turn them on they're locked with a 64-character recovery key that's never shared with Signal.4, 5
- Post-quantumYesSignal added post-quantum keys to chats in 2023 (PQXDH) and began rolling out post-quantum re-keying (SPQR) in October 2025.2, 3
- Who holds the keys
- Your devices. Signal never has them, and your backup recovery key stays with you.
- What Signal Foundation can still see
- Signal says the only account data it can hand over is the date the account was created and the last date it connected.
Email is worth checking next: Gmail, Outlook and iCloud Mail can all read your mailbox. See which email services can.
Is Signal end-to-end encrypted by default?
Yes. Signal says every message and every call is end-to-end encrypted, every time, and that privacy isn't an optional mode1. Group chats are sealed too.
You can check you're talking to the right person by comparing safety numbers1. Since August 2026, Signal can also check a contact's keys for you automatically6.
Is Signal quantum safe?
Yes, against chats recorded today and opened later. In 2023 Signal added PQXDH, which mixes a post-quantum key with the usual one when a chat starts, so an attacker would have to break both2.
In October 2025 Signal began rolling out SPQR, which keeps adding post-quantum keys as a chat goes on. Signal calls the result the Triple Ratchet3. It's rolling out gradually, and chats with someone on an older version use the previous protocol until they update3. As of 25 October 2026, Signal hasn't said the rollout is finished.
Are Signal backups encrypted?
Yes. Signal Secure Backups are optional. When you turn them on, the backup is locked with a 64-character recovery key that's never shared with Signal, so no one, including Signal, can read it4.
The free plan keeps all your texts and the last 45 days of media4. Since September 2026, backups work on Android, iPhone and desktop5. If you lose the recovery key, Signal can't restore the backup for you4.
What can Signal see about me?
Very little. When Signal gets a legal demand, it says the only account data it can produce is when the account was created and the last date it connected to Signal7.
Signal publishes these demands and its replies on its website7.
How Signal compares
Sorted by how many parts are sealed by default, then by how many can be. Ties go A to Z.
Sources
- Is it private? Can I trust it?, Signal. Read on 25 Oct 2026.
- Quantum Resistance and the Signal Protocol (19 September 2023), Signal. Read on 25 Oct 2026.
- Signal Protocol and Post-Quantum Ratchets (2 October 2025), Signal. Read on 25 Oct 2026.
- Signal Secure Backups, Signal. Read on 25 Oct 2026.
- Back to Backups: A Year in Review (28 September 2026), Signal. Read on 25 Oct 2026.
- Introducing Automatic Key Verification (11 August 2026), Signal. Read on 25 Oct 2026.
- Government communication, Signal. Read on 25 Oct 2026.
Changes to this answer
- First published.