The IANA SIP Parameters registry lists response code 403 with the description Forbidden and RFC 3261 as its reference.

Checked 2026-09-30

Vendor
IANA
Product
SIP
Subsystem
response codes
Deployment
any
Region
not restricted
Release range
registry as updated 2026-08-17
Checked
2026-09-30

Sources

Cite this note

APA

WarmTransfer. (2026, September 30). Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-iana-403-row. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-iana-403-row

BibTeX

@misc{warmtransfer-claim-sip-403-forbidden-troubleshooting-iana-403-row,
  title  = {Troubleshooting SIP 403 Forbidden from a carrier: source note sip-403-forbidden-troubleshooting-iana-403-row},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-403-forbidden-troubleshooting-iana-403-row},
  note   = {Source note sip-403-forbidden-troubleshooting-iana-403-row, checked 2026-09-30}
}

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