How to Port Your Business Phone Number Without Missing a Call

Your business phone number is on your website, your Google listing, your trucks, and your customers' contact lists. Changing phone providers shouldn't mean changing it, and in the US it doesn't have to. Moving a number from one provider to another is called porting, and the rules protect your right to do it.

Most ports go smoothly. The ones that don't usually fail for boring reasons: a name that doesn't match the bill, a missing PIN, or an old account that someone cancelled too early. This guide covers what to gather, the order to do things in, how long each type of port takes, and how to cut over without missing calls.

Your right to keep your number

The FCC's consumer guide on keeping your phone number when you change providers sets out the basics:

• You can keep your number when you switch, as long as you stay in the same geographic area. Porting works between landline, VoIP, and wireless providers.
• Your current company cannot refuse to port your number, even if you still owe it money. You still owe the balance, but it can't hold the number hostage.
• FCC rules require simple ports to be processed within one business day. Wireless-to-wireless ports often finish within hours. Other types can take longer.
• Providers may charge a fee to port.
• The FCC's key warning: don't cancel your existing service before the new service is set up.

The two documents every port needs

The letter of authorization (LOA). This is your signed permission for the new provider to move the number. The porting guide from Bandwidth, a US carrier, says an LOA is required before a port order starts. Sometimes a copy of the bill is required too. Some providers send the LOA electronically. Twilio, for example, emails it to the authorized person and cancels the request if it isn't signed within 30 days.

A recent bill or the customer service record (CSR). The CSR is your current carrier's record of the account: the name, service address, and numbers on it. The new carrier uses it to check that the request is legitimate. Bandwidth notes that some carriers release the CSR only to the account holder, so ask for it early.

What to gather before you start

Collect all of this before you start a port request. Every item has to match your current carrier's records exactly.

1. The numbers to move. List every number, including fax lines and any numbers that only forward somewhere.
2. The account number with your current provider. It's often different from the number on your invoice header, so check the bill or ask support.
3. The account PIN or passcode. Bandwidth's guide lists a wrong PIN as one of the most common reasons ports are rejected.
4. The business name exactly as it appears on the bill, including "LLC" or "Inc."
5. The service address on the account. This is where the service is registered, which may not be your mailing address.
6. The billing telephone number (BTN), the main number the account is billed under.
7. The authorized person's name. The person who signs the LOA should be someone the carrier recognizes on the account.

Porting from a mobile carrier

If the number is on a cell phone plan, you need a Number Transfer PIN in addition to the account number:

• Verizon: dial #PORT from the phone or use My Verizon. The PIN expires after 7 days.
• AT&T: dial *PORT or use the app. AT&T's support page says the PIN lasts 4 days, or 14 days for business accounts. If Wireless Account Lock is on, it blocks the transfer.
• T-Mobile: the primary account holder turns off Port Out Protection and creates a temporary port-out PIN. T-Mobile's transfer guide explains the steps.

PINs expire, so get the PIN on the day you submit the request.

Full ports and partial ports

If you move every number on an account, that's a full port. The old account usually closes once the port completes.

If you move only some numbers, it's a partial port. You'll need to tell the old carrier what happens to the numbers left behind. If the main billing number is one of the numbers you're moving, the old account needs a new BTN. Ports often stall here, so decide before you submit.

How long porting takes

Timing depends on the type of number and the carriers involved. Bandwidth's guide gives these estimates, which are goals and not guarantees:

Telnyx says toll-free ports take about two business days but can range from one to seven. It recommends starting at least two weeks before you need the number on the new system. That's good advice for any port with a deadline, like an office move or a contract end date.

Step-by-step: porting without missing calls

1. Set up the new phone system first

Before you request the port, get the new service fully working on a temporary number:

• Add your team and their extensions.
• Record your greeting and build the call routing (see our auto-attendant setup guide).
• Install the apps on phones and computers, and plug in any desk phones.
• Make and receive test calls.

When the port completes, your real number drops into a system that already works.

2. Submit the port request

Enter the details exactly as they appear on the bill, attach the signed LOA and a recent invoice or CSR, and pick a target date if your provider allows one. Avoid your busiest day of the week.

3. Keep the old service active

Leave the old account alone. Don't cancel it, don't stop paying it, and don't remove the numbers. Bandwidth's guide warns that disconnected or inactive numbers can't be ported. Cancel only after every number has moved and you've tested it.

4. Watch for rejections and fix them fast

If a port is rejected, the reason is usually specific: a name mismatch, a wrong PIN, a service address that doesn't match, or a missing number on a partial port. Fix the detail and resubmit. Rejections are common and usually quick to correct.

5. Test on cutover day

When the port completes:

• Call the main number from a cell phone and walk through every menu option.
• Check that texts arrive if the number is text-enabled. Texting may need its own registration on the new system (10DLC for local numbers).
• Make an outbound call and check the caller ID.
• Leave a voicemail and confirm it reaches the right person.

6. Cancel the old account

Only after testing, cancel any remaining service with the old provider and keep the final bill for your records.

Common porting mistakes

• Cancelling first. The most expensive mistake. A cancelled number can be lost.
• Guessing account details. Copy them from the bill.
• Forgetting secondary numbers. Fax lines, old marketing numbers, and the number printed on your trucks.
• Expired wireless PINs. Generate the PIN on the day you submit.
• Porting during a busy week. Pick a quiet day and tell your team when the switch will happen.
• Missing the texting setup. Calls and texts move with the number, but business texting from a local number still needs 10DLC registration on the new provider.

Porting to D Line

In D Line, you start a port from your workspace under Phone numbers → Port a number in. The form asks for the details in the checklist above: the numbers, the account PIN for wireless accounts, the business name and billing number on the account, the service address, and what should happen to any numbers you leave behind. You upload the signed LOA and a recent invoice or CSR. We review eligibility, confirm the timeline before anything moves, and keep you updated while the carrier processes the request.

Porting a number in to D Line is free: there is no port-in fee. You can set everything up first on the number that comes with your workspace, so your team is ready on cutover day. A 14-day trial costs $3, and our support team is available around the clock if a port needs a hand. See pricing for plan details, or contact us to check a list of numbers before you switch.

If you're comparing providers, our guides to Unitel Voice alternatives and iPlum alternatives cover what each one charges to move numbers in and out.

Quick checklist

• List every number you want to move
• Copy the account number, name, service address, and BTN from a recent bill
• Get the account PIN, plus a fresh transfer PIN for wireless numbers
• Decide what happens to any numbers you leave behind
• Set up and test the new system on a temporary number
• Submit the port with the signed LOA and a recent invoice or CSR
• Keep the old service active until the port completes
• Test calls, texts, caller ID, and voicemail on cutover day
• Cancel the old account