A Teams number can carry an extension of 1 to 12 digits after the ';ext=' delimiter; if one is assigned, the inbound called number must include it for lookup to match, and Microsoft says extensions are only needed when users share a main number without a Shared Calling policy.
Checked 2026-09-25
- Vendor
- Microsoft
- Product
- Teams Phone
- Subsystem
- inbound routing
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-09-25
- Checked
- 2026-09-25
Sources
- Microsoft Teams Dial plans for phone call routing — Microsoft · tier 2 current vendor documentation · Number lookup for inbound calls section, Extension bullet and following paragraphs
Cite this note
APA
WarmTransfer. (2026, September 25). Unified CM and Teams Phone coexistence during a migration: source note cucm-teams-coexistence-rnl-extension-format. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-teams-coexistence-rnl-extension-format
BibTeX
@misc{warmtransfer-claim-cucm-teams-coexistence-rnl-extension-format,
title = {Unified CM and Teams Phone coexistence during a migration: source note cucm-teams-coexistence-rnl-extension-format},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-teams-coexistence-rnl-extension-format},
note = {Source note cucm-teams-coexistence-rnl-extension-format, checked 2026-09-25}
}