If Teams voice routing has no route for Unified CM number ranges ahead of the general PSTN route, Teams calls to users still on Unified CM will match the PSTN route and leave through the carrier, so calls between the two platforms depend on carrier trunks and are subject to carrier call charges.
inferred · Checked 2026-09-24
- Vendor
- Microsoft
- Product
- Teams Phone Direct Routing
- Subsystem
- voice routing
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-24
- Status
- inferred
- Checked
- 2026-09-24
Sources
- Configure call routing for Direct Routing — Microsoft · tier 2 current vendor documentation · Derived from Example 2 Note on PSTN usage order and the Example 2 routing table
Cite this note
APA
WarmTransfer. (2026, September 24). Building a hybrid Unified CM and Teams Phone environment for a phased migration: source note cucm-teams-hybrid-build-inf-pstn-path. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-teams-hybrid-build-inf-pstn-path
BibTeX
@misc{warmtransfer-claim-cucm-teams-hybrid-build-inf-pstn-path,
title = {Building a hybrid Unified CM and Teams Phone environment for a phased migration: source note cucm-teams-hybrid-build-inf-pstn-path},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-teams-hybrid-build-inf-pstn-path},
note = {Source note cucm-teams-hybrid-build-inf-pstn-path, checked 2026-09-24}
}