181
SIP
181 Call Is Being Forwarded
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
On this page
When You See This Code
When the callee has call forwarding enabled and the request is being redirected to another number or device.
How to Fix
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Specification
Compare With
Guides
401 Unauthorized vs 403 Forbidden: When to Use Each
Security & Authentication
SIP Response Codes: Understanding VoIP Call Flow
Real-Time Protocols
SIP Call Flow: Understanding Session Setup
Real-Time Protocols
WebRTC Signaling with SIP and WebSocket
Real-Time Protocols
RFC 3261: SIP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
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TLS Versions
Frequently Asked Questions
What is SIP 181 Call Is Being Forwarded?
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
When do you see SIP 181 Call Is Being Forwarded?
When the callee has call forwarding enabled and the request is being redirected to another number or device.
How to fix SIP 181 Call Is Being Forwarded?
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.