485
SIP
485 Ambiguous
The Request-URI was ambiguous. The response body may contain a list of possible unambiguous addresses.
On this page
When You See This Code
When the destination address matches multiple users and the server cannot determine which one is intended.
How to Fix
Use a more specific SIP URI. Check the response body for a list of possible matches and select the correct one.
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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Frequently Asked Questions
What is SIP 485 Ambiguous?
The Request-URI was ambiguous. The response body may contain a list of possible unambiguous addresses.
When do you see SIP 485 Ambiguous?
When the destination address matches multiple users and the server cannot determine which one is intended.
How to fix SIP 485 Ambiguous?
Use a more specific SIP URI. Check the response body for a list of possible matches and select the correct one.