The BYOC SBC settings include an 'Allow REFER support to transfer calls' option (Zoom Phone only) that makes Zoom accept SIP REFER messages from that SBC.

Checked 2026-09-24

This Zoom Phone setting ensures that the Zoom infrastructure accepts SIP REFER messages from this SBC.
Vendor
Zoom
Product
Zoom Phone
Subsystem
byoc-p-sip
Deployment
hybrid
Region
not restricted
Release range
current as of 2026-09-24
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Zoom Phone routing and PSTN connectivity: source note zoom-phone-routing-sbc-refer-setting. WarmTransfer. https://warmtransfer.net/knowledge/claims/zoom-phone-routing-sbc-refer-setting

BibTeX

@misc{warmtransfer-claim-zoom-phone-routing-sbc-refer-setting,
  title  = {Zoom Phone routing and PSTN connectivity: source note zoom-phone-routing-sbc-refer-setting},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/zoom-phone-routing-sbc-refer-setting},
  note   = {Source note zoom-phone-routing-sbc-refer-setting, checked 2026-09-24}
}

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