POTS REPLACEMENT
Replacing Copper Lines? Don’t Lose the Numbers You Rely On
When a site moves off a copper phone line, the new device can be working on a temporary number while the original number is still waiting to transfer. If the old copper service is cancelled in that gap, the number your elevator, alarm monitoring, callers and records depend on can be disconnected. The fix is a simple rule: no copper cancellation until the receiving provider confirms the number transfer is complete and the final number has been tested.
This article covers what the FCC says about moving a number, three things to confirm before each transfer, how to make the cancellation rule work across many sites, and who is responsible for each check.
A working device is not a moved number
Moving a number from one provider to another is called “porting.” The FCC says numbers can generally be ported between wireline, internet-based (IP) and wireless providers, as long as you stay in the same geographic area. Some rural wireline providers may have state waivers from porting, so not every number can move.
The FCC’s advice on timing is direct: do not terminate service with your existing company before starting new service with another company. FCC rules require a simple port to be completed within one business day and a non-simple port within four business days, unless the new provider or the customer asks for longer. The FCC defines a simple port as one involving an account with a single line, so plan for the longer window when a number sits on a multi-line business account.
The stakes are real once a number is disconnected. Under FCC numbering rules, a disconnected business number must be held for at least 45 days, and no more than 365, before it can be assigned to someone else. It could go to another customer in as little as 45 days, and the holding period is not a promise you can get it back.
Not every number needs to move. Keep the numbers that people outside your organization dial, such as fax lines that receive documents and your main published numbers. Lines that only dial out, such as most alarm communicators, credit card terminals and many elevator phones, can often take a new number once the monitoring company or contractor updates its records. Where a new number works, the changeover is simpler: there is no port request to get right, and the new line can run alongside the old one until it passes testing. The same rule still applies before cancelling: test the new number and update every record that holds the old one.
Confirm three things before each transfer
- Whether the number must be kept. Ask the elevator contractor, alarm monitoring company and IT team where the number is used: monitoring records, callback instructions, building directories, other systems’ settings. If a new number is acceptable, list every place it must be updated.
- That the account details match. A port request generally has to match the current provider’s records, such as the account number, account name and service address, and come from someone authorized on the account. Use the latest bill from the current provider, not the building’s trade name.
- What stays behind. Find out whether the number is the account’s main billing number and whether other lines ride on that account. Ask both providers: “What will remain active after this number moves?”
Make confirmation the gate at every site
At one building, this is a careful project manager. Across hundreds of sites, it needs to be a rule.
- Record two numbers per line. Log the temporary number and the final number separately, so an early test on the temporary number is never mistaken for proof the final number works.
- Require written port confirmation. The receiving provider confirms the transfer is complete and the final number is active. A scheduled date, an installed device or a successful outbound call is not confirmation.
- Test the final number where it matters. The elevator contractor confirms the call reaches the right answering point, two-way voice works, the cab and building are identified correctly, and a call back to the final number reaches the cab. The alarm monitoring company confirms it receives test signals against the correct site and account. Some fire officials require this in writing: Delaware’s State Fire Marshal, for example, requires an attestation that alarm, trouble and supervisory signals were retested to the supervising station after a move from copper to cellular or radio service. Your local fire official decides what applies to you.
- Then cancel, and check the final bill. Finance releases the cancellation only after steps 2 and 3 are on file, then confirms the final bill closes the old line and nothing intended to remain.
Who does what: facilities owns the site list and test scheduling, the receiving provider confirms the port, the elevator and alarm contractors run the tests, IT updates any system that stores the number, and finance holds the cancellation until the record is complete.
Separate the carrier’s network changes from your cutover
Updated FCC rules on copper retirement and service discontinuance are now in effect. They change how carriers give notice before retiring copper and how they get approval to discontinue a service. They do not set a porting deadline for customers, and they do not mean a carrier’s notice has moved your number. Your number moves only when you request a port and the receiving provider completes it.
Our perspective
The simplest protection in a copper replacement project is a single rule that finance, facilities and IT all follow: no cancellation order without port confirmation and a tested final number. It needs no new technology, it scales from one site to hundreds, and it puts each check with the party that can actually verify it. Nadicent helps multi-site organizations build that sequence into their POTS replacement plan so every line is accounted for before the old service ends.
Who in your organization signs off before a copper line is cancelled?
Sources
- Federal Communications Commission, “Porting: Keeping Your Phone Number When You Change Providers,” consumer guide
- Federal Communications Commission, “Porting: Keeping Your Phone Number When You Change Providers,” printable guide, last reviewed March 9, 2020, via U.S. Government Publishing Office
- Electronic Code of Federal Regulations, 47 CFR 52.35, “Porting intervals”
- Electronic Code of Federal Regulations, 47 CFR 52.15(f)(1)(ii), “Aging numbers”
- Federal Register, Federal Communications Commission, effective-date notice, 91 FR 62334, October 1, 2026
- Delaware Office of the State Fire Marshal, “Change of Fire Alarm Service” form, updated April 16, 2024
- Kelley Drye & Warren LLP, “FCC Issues Order Standardizing Number Porting Process,” client advisory, May 24, 2010
This article is general information, not legal or compliance advice. Requirements vary by location and change over time, so check the sources above and confirm with your local authorities and licensed contractors.
