Source note · Call blocking and analytics labeling remediation
The 2020 Fourth Report and Order (FCC 20-187) required terminating providers blocking on IP networks to return SIP 607 or 608 and ISUP code 21 on TDM networks, with compliance by 1 January 2022.
Checked 2026-09-24 · superseded by call-blocking-labeling-cease-603-607-608
We require that terminating voice service providers that block calls on an IP network return SIP Code 607 or 608, as appropriate.
- Vendor
- FCC
- Product
- FCC 20-187
- Subsystem
- blocking-notification
- Deployment
- pstn
- Region
- us
- Release range
- FCC 20-187; superseded for analytics blocking by FCC 25-15
- Checked
- 2026-09-24
Sources
- Advanced Methods to Target and Eliminate Unlawful Robocalls, Fourth Report and Order (FCC 20-187) — Federal Communications Commission · tier 1 standards and regulators · Paras. 56 and 61, Section III.C.1
Cite this note
APA
WarmTransfer. (2026, September 24). Call blocking and analytics labeling remediation: source note call-blocking-labeling-fourth-ro-607-608. WarmTransfer. https://warmtransfer.net/knowledge/claims/call-blocking-labeling-fourth-ro-607-608
BibTeX
@misc{warmtransfer-claim-call-blocking-labeling-fourth-ro-607-608,
title = {Call blocking and analytics labeling remediation: source note call-blocking-labeling-fourth-ro-607-608},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/call-blocking-labeling-fourth-ro-607-608},
note = {Source note call-blocking-labeling-fourth-ro-607-608, checked 2026-09-24}
}