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SIP Connect

Nexmo supports SIP Connect, allowing you to dial in to the Nexmo Platform directly from your own infrastructure.

Connecting from a SIP endpoint to a Nexmo application enables you to dynamically handle calls and connect out to mobile, landline, SIP and IP endpoints.


Currently, you need to dial a Nexmo virtual number that is attached to an application. This is how Nexmo routes your call to the correct answer_url.

To test this functionality have your PBX forward calls to Here is an example of doing so with an Asterisk extension, transmitting a custom header that will be sent to your answer_url:

exten => 69100,1,SIPAddHeader(X-UserId:ABC123)
exten => 69100,2,Dial(SIP/nexmo/14155550100)

Domain-based routing

If you are using SIP Connect and require your call to be handled by a specific Nexmo region, then you can specify that by using R-URI with such information in the domain part.

The following code will indicate to Nexmo that you want this SIP Connect call to be handled in the EU:

Available domains are the same as the A records: