In addition to supporting end-to-end encrypted messages and calls with other Signal users, Signal Android can be configured as your default SMS/MMS app. Learn how to distinguish when communication is private (Signal message) or insecure (SMS/MMS).
Insecure media and group messages (MMS) are transmitted through your mobile plan and incur fees as set by your mobile plan. Signal has a size limit of 300kb for sending MMS.
- Confirm you have SMS (text) or MMS (Group and media) as part of your mobile plan and that you are connected to your mobile network.
- Enable Signal Settings > SMS and MMS > 'WiFi Calling' compatibility mode and try again.
- Confirm all the application permissions are enabled for Signal.
- For some devices, if you restart your phone then re-download the MMS, it will succeed.
- Check your other SMS/MMS app. Even if the other app is not open, it may still attempt to retrieve the MMS before Signal can.