IMPORTANT NOTICE: FCC Do Not Originate (DNO) Call Blocking Rules
Dear Valued Business Customer,
We are writing to inform you of an important regulatory change from the FCC that will enhance the integrity of the voice telecommunications network.
What's Changing
Effective December 15, 2025, the Federal Communications Commission (FCC) requires all voice service providers to implement Do Not Originate (DNO) blocking. This means IntelePeer and other carriers must block call attempts when the calling number is an invalid telephone number that no legitimate caller should be using.
This new policy is designed to combat illegal robocalling and caller ID spoofing by scammers and fraudsters. Bad actors frequently disguise their identity by spoofing phone numbers--sometimes selecting numbers randomly, which can result in the use of invalid or unassigned numbers. While it remains challenging to stop calls that spoof legitimate phone numbers, blocking calls from demonstrably invalid numbers is straightforward, as there is no legitimate reason for any caller to use such numbers.
What Constitutes an Invalid Calling Number
A phone number is considered invalid and will be blocked if the number populated in the SIP Invite’s From header matches either of the following conditions:
1. Do Not Originate Designation: The number's owner has designated it for inbound calls only, indicating that all outbound calls from that number are, by definition, unauthorized and spam.
2. Unassigned or Undefined Numbers: The number is undefined or otherwise unassigned according to the North American Numbering Plan (NANP). For example, phone numbers are invalid if they have an area code (NPA) or exchange (NPA-NXX) that does not exist in the NANP.
You are not required to use calling numbers assigned in your IntelePeer inventory. If you place calls through IntelePeer using calling numbers you procured through another number provider, that is a legitimate and valid use case. Your use of non-inventory numbers will affect whether your calls receive STIR/SHAKEN A attestation versus B attestation, but using numbers outside your IntelePeer inventory does not make them invalid, and you do not need to provide evidence to IntelePeer that you are authorized to use those numbers.
What About Private Numbering Plans
If your organization uses private numbers for internal communications (such as between company locations or applications), these numbers may appear to the network as invalid or malformed NANP numbers and will be subject to DNO blocking unless specifically addressed.
If you currently send traffic to IntelePeer using private numbering plans or custom calling number formats for internal applications, please contact IntelePeer as soon as possible to discuss accommodation options for your specific requirements.
What This Means for You
We anticipate this policy will not impact your normal business operations if your equipment is properly configured. However, if your calling equipment is transmitting invalid calling numbers due to misconfiguration, those calls will be blocked by IntelePeer or other carriers in the call path.
When Will This Change Happen
Timeline: The FCC requires all carriers to implement DNO blocking by December 15, 2025. IntelePeer will begin deploying this capability during November 2025, and some other carriers have already implemented their DNO blocking solutions.
Important: DNO blocking may already affect your calls today. Each network in the call path independently applies DNO screening, meaning a call will be blocked if any transit carrier in the route detects an invalid calling number—regardless of whether IntelePeer has completed its DNO deployment. Your outbound calls may traverse networks which already activated DNO blocking.
Action Required
We recommend that you:
• Review your voice equipment configuration to ensure all outbound calls use valid calling numbers.
• Contact your equipment vendor if you need assistance verifying your configuration
Questions or Concerns?
If you have questions about this change or experience any issues with your outbound calling service, please contact Support immediately, using one of these methods: