Number Porting
What Is Number Porting?
Number porting is the process of moving a phone number from one carrier or switch to another while the customer keeps the same number. In the US, it works through local number portability (LNP): a national database records which switch now serves the number, so calls are routed there instead of to the original provider.
How does number porting work?
In the US, a 10-digit Location Routing Number (LRN) identifies the switch or network destination serving a ported number. When a number is ported, the Number Portability Administration Center (NPAC) record associates that number with the applicable LRN so participating networks can route calls correctly. (numberportability.com).
A typical port follows these steps:
Port request. The new (gaining) carrier submits a request with the customer's authorization and account details.
Validation. The current (losing) carrier checks those details against its records. A mismatched name, address or account number is a common reason for rejection.
Firm order commitment (FOC). The carriers agree on a date and time for the port.
Activation. On the FOC date, the number is activated on the new switch and calls begin routing there.
In the US, qualifying simple wireline and intermodal port requests are generally subject to a one-business-day porting interval, provided the request is accurate and complete. Non-simple and larger business ports may require additional time and coordination.
Does a platform migration require number porting?
Not always. When a service provider moves customers from a legacy voice platform to a new one, such as NetSapiens, what happens to the numbers depends on who holds them and how they reach the switch:
Situation | What usually happens |
|---|---|
Numbers stay with the same carrier or SIP trunk provider | The carrier or SBC routing is updated to point numbers at the new platform; no carrier-to-carrier port is needed |
Numbers move between switches or platforms within the same service provider's network | The provider may update internal routing, SBC configuration or, where applicable, number-portability records. The exact process depends on how the numbers are currently hosted and routed |
Numbers move to a different carrier as part of the migration | An inter-carrier port is filed, with the new carrier as the gaining party |
A mix of the above across customers | Each group is planned separately and lined up with its cutover wave |
Working this out early, number by number, is part of migration discovery. It affects how long each cutover wave needs and which third parties need to be involved.
Why does porting timing matter during a cutover?
Inbound calling depends on numbers pointing at the right platform at the right moment. If a port activates before the customer's users and call flows are ready on the new platform, calls can arrive at a switch that cannot complete them. If it activates late, callers keep reaching the legacy platform after users have moved.
Service providers reduce this risk by:
Confirming account details before submitting ports, to avoid rejections that push dates back
Lining up FOC dates with the cutover window for each wave
Keeping the legacy configuration in place until inbound calls are confirmed on the new platform
Updating emergency calling (E911) address records for moved numbers
Test-calling a sample of numbers from outside the network once routing changes
In a Vox Matic migration, number inventory and routing are reviewed during discovery, and applicable carrier and SBC routing changes are included in the cutover plan where they fall within the agreed scope.
Frequently asked questions
How long does number porting take?
Qualifying simple port requests in the US are generally subject to a one-business-day porting interval, provided the request is accurate and complete. Larger business ports are scheduled with the carriers and often take longer, depending on volume and how quickly details are validated.
Will service be interrupted during a number port?
A port is designed to switch routing at a set time on the FOC date. Short interruptions can happen if the new platform is not ready when the port activates, which is why ports are timed with the cutover plan.
Does migrating to NetSapiens require porting our numbers?
Not always. If your numbers stay with the same carrier, they can often be re-routed to the new platform without a carrier-to-carrier port. It depends on how your numbers are held today.
Related terms
Moving customers and their numbers to NetSapiens?
See how Vox Matic plans Metaswitch to NetSapiens migrations, including numbers and routing.
NetSapiens is a trademark of Crexendo, Inc. Metaswitch and BroadWorks are trademarks of their respective owners. Otto™ and Forge™ are trademarks of Vox Matic. Vox Matic is an independent migration services provider. References to third-party products are for identification and interoperability purposes only and do not imply endorsement, except where an authorized partnership is expressly identified.