Moving your business numbers to a new provider without missing calls

Moving phone numbers between providers sounds risky because the numbers are how customers reach you. In practice, a port is mostly paperwork followed by a short, scheduled switch. The calls that go missing are usually the ones where the paperwork was wrong and the date slipped.

What a letter of authorization is

A letter of authorization, often shortened to LOA, is a signed statement that you own the numbers and allow the new provider to move them. Your old provider will compare it with their records. If the name, address or account details do not match, the request is rejected and the clock restarts. The person who signs should have authority over the account, which may not be whoever is managing the project.

Gather the details first

Most rejected ports come from mismatched information. Before you request anything, collect the following from a recent bill or from your account portal:

• The account holder name exactly as the old provider prints it, including punctuation and "Inc." or "LLC".
• The service address on file, which may differ from your office address.
• The account number and any PIN or passcode set for porting.
• A full list of numbers on the account, including fax lines, alarm lines, extensions with their own number and old numbers nobody remembers.
• Which numbers are tied to a bundle, since canceling the account may remove services you want to keep.

Do not cancel the old service. Canceling before the port completes can release the numbers, and getting them back is slow or impossible. Let the port itself close the account lines, then deal with the contract.

A worked example

Halcyon Dental is moving a main number, 000-000-0134, and eleven location lines. The office manager pulls the last bill and finds the account is in the name "Halcyon Dental Group, LLC" while the website says "Halcyon Dental". She uses the bill's version on the letter of authorization. She also finds two lines on the bill that nobody recognized: a fax line used by a records clinic, and a line wired to an alarm panel at one location. Both go onto the port list, because an unported line stays with the old provider and keeps billing.

One location's lines sit on a different account with a different holder. She splits the request into two ports, each with its own letter and its own bill, so one mismatch cannot hold up the other.

Choose the cutover window

Once the old provider accepts the request, a date is set. The numbers move at a scheduled time, and for a short period some calls may fail to connect. Pick a window when call volume is lowest. For most offices that means early in the morning or late in the evening, midweek, away from month end and from any known busy day.

With Tizbo you choose the cutover window yourself, so a team that is quiet at 6 a.m. can switch then and avoid whatever time suits the old provider. Whichever provider you use, ask who will be available at that time, on both sides.

Build and test before the switch

Your new system should already be configured on temporary numbers before the cutover. Call it and listen to it.

1. Place calls to each temporary number and follow every menu branch.
2. Check that calls reach the right people, ring the right devices and fall through to voicemail correctly.
3. Test outbound calls and confirm the caller ID shown is the number you plan to keep.
4. Write down a rollback plan: who to call and what to say if something is wrong after the move.

Common mistakes

• Canceling the old service before the port is complete.
• Submitting a letter signed by someone who is not on the account.
• Leaving out lines nobody thinks of as phone numbers, such as faxes, alarms and elevator phones.
• Changing the account name, address or contact on the old provider's side after the request is filed.
• Scheduling the cutover for a Monday morning because it is convenient for the project plan.

What callers experience

If the port goes to plan, callers notice nothing. A few might hear a brief delay or a busy tone around the switch, and calling again works. Keep the old system running in the background until the port is confirmed, and consider forwarding the old lines to a mobile for the first hour.

Right after the cutover, call each number from a mobile phone and from another office line, since they can reach you by different routes. Check inbound, outbound and any faxes. Then watch the first day of real calls closely, and keep a short list of anything odd to raise with your provider.

A timeline you can copy

1. Weeks before: collect bills, list every number, find the account holder and any porting PIN.
2. Next: sign the letter of authorization and submit the request, with temporary numbers set up in parallel.
3. Once a date is confirmed: choose the cutover window and tell staff and any outside parties who need to know.
4. The day before: run the test calls again and confirm who is on call.
5. Cutover and the day after: test inbound, outbound and faxes, then watch real calls.

What to ask a provider

• How long do ports usually take for my kind of number, and what makes them slower?
• Can I choose the time of day for the cutover?
• What do you check on my paperwork before submitting it?
• Who is reachable during the cutover window, and how do I reach them?
• What happens if the port is rejected, and can the new service run on temporary numbers meanwhile?