Skip to main content
Signal calls are end-to-end encrypted using the Signal Protocol over WebRTC. Audio and video streams are encrypted before leaving your device and can only be decrypted by the other participants — Signal’s servers relay the connection but cannot access call content.

​
Starting a 1:1 voice call

1

Open a conversation

Navigate to the chat with the contact you want to call.
2

Tap the phone icon

Tap the phone icon in the top-right corner of the conversation. Signal dials the contact and plays an outgoing ring tone while waiting for them to answer.
3

Wait for the other person to answer

Once they accept, the call connects and you hear a brief chime. The call state transitions from Dialing through Remote ringing to Connected.
You can also start a voice call from the Calls tab. Tap the compose icon, search for or select a contact, then choose the voice call option.

​
Starting a 1:1 video call

1

Open a conversation

Navigate to the chat with the contact you want to call.
2

Tap the video icon

Tap the video camera icon in the top-right corner of the conversation. Your front camera activates and the call goes out with video enabled.
3

Connect

When the contact answers, both video feeds appear on screen. Your local preview shows in a smaller picture-in-picture overlay.

​
Starting or joining a group call

Group calls are available in any group conversation. Signal tracks whether a call is currently active and shows how many participants have joined.
1

Open the group conversation

Navigate to the group chat.
2

Start or join the call

Tap the video icon at the top of the conversation to start a new group call, or tap the Join button on the active call banner if a call is already in progress. Tapping Join on an existing call sets your event state to Joined rather than starting a new ring.
3

Invite others (optional)

Once inside the call, you can ring individual group members who have not yet joined by selecting them from the participant list.
Group calls support voice and video. The call is associated with the group and its history appears in both the group conversation and the Calls tab.

​
Incoming call handling

When someone calls you, a notification appears on your screen with the caller’s name or number.

Accept

Swipe up or tap Accept to answer the call. If the caller initiated a video call, your camera activates automatically.

Decline

Tap Decline to reject the call. The caller sees a missed call notification on their end.
If you are already in a call when another call arrives, the new call is automatically marked as missed. A snackbar notifies you that you are already in a call. If a notification profile is active that silences calls, incoming calls are automatically declined and logged as Missed (notification profile) in your call history.

​
In-call controls

During a call, a set of controls appears at the bottom of the screen:
The flip camera control is available when your device has more than one camera. Tapping it cycles between Front and Back directions.

​
Call history and logs

All calls — incoming, outgoing, missed, and declined — are recorded in the Calls tab.
  • All calls shows every call event sorted by time.
  • Missed filter shows only calls where you did not answer, where the ring expired, or where you declined. Pull down on the call list to enable this filter, or use the filter menu in the toolbar.
Each entry in the call log shows the contact or group name, call type (voice or video), direction (incoming or outgoing), and timestamp. Tapping a 1:1 call entry opens conversation settings. Tapping a group call or call link entry opens the call details screen.

​
Deleting call history

  • Single entry: Long-press an entry and choose Delete from the context menu.
  • Multiple entries: Long-press to enter selection mode, select entries, then tap the delete action in the bottom bar.
  • Clear all history: Open the overflow menu in the toolbar and choose Clear call history. This permanently deletes all call events.
Clearing call history is permanent. Call events are removed from the local database and cannot be recovered.

​
Call quality and data usage

Signal adjusts call quality based on your configured data mode. You can set this in Settings → Chats → Call data mode: After a call ends, Signal may prompt you with a brief quality survey. This is optional and only appears occasionally to help improve call reliability.

​
How calls are encrypted

Signal calls use the Signal Protocol combined with WebRTC for secure voice and video transport.
  • Key agreement: When a call is initiated, Signal performs a Diffie-Hellman key exchange to derive a shared secret that never leaves your device.
  • Media encryption: Audio and video packets are encrypted with SRTP (Secure Real-time Transport Protocol) using keys derived from that exchange.
  • No server access: Signal’s infrastructure relays encrypted WebRTC packets but holds no decryption keys. The call content is only accessible on the devices of the call participants.
  • Safety numbers: The same identity keys used for messaging back the call’s encryption. You can verify them in the conversation’s safety number screen to confirm you are talking to the right person.

Encryption overview

Learn how the Signal Protocol protects messages and calls end-to-end.

Call links

Share a link to let anyone join a Signal call without being in your contacts.