What it means
The server understood the request but refuses it. Unlike 401, no credentials will help. This is very often an IP allowlist, an account provisioning issue, or a rejected caller identity.
SIP/2.0 403 Forbidden
Common causes
- Your source IP is not on the provider's allowlist or ACL
- The account or trunk is not provisioned or is suspended
- The From or PAI identity is not authorized to place this call
- The dialed destination is blocked by policy such as international or premium restrictions
- Credentials were accepted but the action is not permitted
How to fix it
- Confirm your public IP is registered on the provider's allowlist
- Check the trunk or account is active and provisioned for this call type
- Set a From and PAI the provider recognizes as yours
- Verify the destination is permitted on your plan
- Contact the provider with the exact Call-ID if all of the above look correct
See it in your own trace
Paste a full SIP or Asterisk log into the decoder and ladder tools to see exactly where this response appears in the call and what led to it. Everything runs in your browser, so your logs never leave your device.
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