Hi team, I have a question about retrieving an intermediate phone number in a multi-number call flow. Here’s my scenario: A customer calls a client. That client routes their phone number to a Telnyx-purchased number (the destination). So this flow involves three phone numbers: The originating caller’s number The client’s phone number that receives the initial call and forwards/redirects it to Telnyx The Telnyx number that ultimately handles the call I know Telnyx can provide call details for the originating caller and the final destination (Telnyx number), but is it possible to retrieve the intermediate phone number (the client’s number that receives and then redirects)? If Telnyx doesn’t support this, are any SIP trunk providers capable of exposing that intermediate number — aside from Twilio, which I know doesn’t support local/mobile numbers in Belgium? Thanks in advance!

Telnyx can only show the intermediate number if it’s passed in SIP headers (like Diversion or History-Info) by the client’s carrier. If the forward just re-originate the call, that number isn’t visible to Telnyx. Most SIP providers work the same way they can’t expose what isn’t sent. Best option is enabling those headers on the forwarding carrier or routing the client number directly via SIP to Telnyx. @nhalflants

Usually, Telnyx will only show the number it receives the call from and the final destination. The intermediate client number often doesn’t come through unless it’s explicitly passed in SIP headers, and most carriers don’t include that. The only reliable way to see it is if the client’s forwarding happens through a SIP system they control, which can preserve that info. Out of curiosity, is their forward set up via a carrier or a SIP PBX? @nhalflants

Adam and James are both correct here. If its possible to enable the diversion header on the forwarding client, that'll contain the originating number.