Keep your existing business phone number when switching to a SIP trunk provider. This guide covers everything from gathering your account information to completing the cutover with zero downtime.
Number porting (Local Number Portability or LNP) lets you transfer your existing phone number from one carrier to another. When you switch to a SIP trunk provider like IPComms, you do not need to change your phone number. The FCC mandates that carriers must release numbers when customers request a port.
The process involves your new provider (the "winning carrier") submitting a port request to your current provider (the "losing carrier"). Once approved, calls to your number route to your SIP trunk instead of your old carrier.
Before You Start
Before submitting a port request, make sure you have these things in order:
Active Service
Do NOT cancel your current service before the port completes. The number must be active to port.
SIP Trunk Ready
Have your SIP trunk configured and tested with a temporary number first.
No Pending Changes
Cancel any pending orders or changes with your current carrier.
Account in Good Standing
Pay any outstanding balances. Past-due accounts can delay ports.
Step 1: Gather Your Account Information
The port request requires exact account details that match your current carrier's records. Any mismatch will cause a rejection.
Information
Where to Find It
Notes
Account Number
Your monthly bill or online account
Not your phone number
Account PIN/Password
Call your carrier or check account settings
Some carriers use a separate transfer PIN
Authorized Name
Name on the account (person or business)
Must match exactly, including LLC/Inc
Service Address
Address associated with the account
Must match exactly, including unit/suite
Phone Numbers
List all numbers to port
BTN (main number) + additional DIDs
Current Carrier
Your bill or CSR document
May differ from reseller name
Building this? Your PBX will need a number
Find a phone number for your trunk
Local numbers $1.50 a month, toll-free $2.00, $1.00 one-time setup. Pick one here and it carries into signup.
Enter an area code, or wait a moment for numbers near you.
With IPComms, you can submit a port request through our customer portal or by contacting support.
Sign the LOA (Letter of Authorization)
The LOA is a legal document that authorizes IPComms to port your number. It must be signed by the account holder. The LOA includes:
Your name and business name
Service address on file with current carrier
Phone numbers to be ported
Authorization to release the numbers
Signature and date
Provide a Recent Bill
Most carriers require a copy of your most recent phone bill to verify account ownership. The bill should show the account holder name, account number, phone numbers, and service address.
Submit via IPComms Portal
Log into the IPComms customer portal and navigate to Phone Numbers > Port Request. Upload your LOA and bill copy, fill in your account details, and submit. You will receive email updates as the port progresses.
Step 3: Understand the Porting Timeline
Porting timelines vary depending on the type of number and carrier:
Port Type
Typical Timeline
Details
Wireless to SIP
2-5 business days
Fastest port type
Landline (simple)
3–10 business days
Single line, no complex features
Landline (complex)
10-20 business days
PRI/T1, multiple numbers, hunt groups
Toll-free numbers
3–10 business days
Managed by RespOrg transfer
VoIP to VoIP
3-7 business days
Usually faster than landline
Step 4: Get Your FOC Date
Once your port request is accepted, you will receive a FOC (Firm Order Commitment) date. This is the confirmed date when the number will transfer to IPComms.
After receiving the FOC date:
Verify your SIP trunk is configured and tested
Ensure your Asterisk dialplan handles inbound calls to the ported number
Plan for a brief interruption (usually under 15 minutes during cutover)
Have your old system ready as a fallback if needed
Step 5: Day of Cutover
On the FOC date, the port happens automatically:
Port Activates
The number transfers in the carrier routing database (NPAC). Usually happens in the morning.
Calls Start Routing
Within minutes of activation, incoming calls route to IPComms and your SIP trunk.
Verify Inbound
Test by calling the ported number from a cell phone. Verify it rings on your Asterisk system.
Verify Outbound Caller ID
Make an outbound call using the ported number as caller ID. Verify it displays correctly.
Cancel Old Service
Only after verifying everything works, contact your old carrier to close the account.
Common Port Rejections and Fixes
Rejection Reason
Fix
Name mismatch
Use the exact name on the account. "John Smith" is not "John A. Smith"
Address mismatch
Use exact address format from your bill. "St" vs "Street" matters
Account number wrong
Check your bill. Some carriers have sub-account numbers
PIN/password incorrect
Call your carrier to verify or reset your transfer PIN
Number not on account
Verify the number is listed on this specific account
Pending order exists
Cancel any pending changes with your current carrier
Number frozen
Call carrier to remove port-out freeze (they must comply per FCC)
Pro Tips for Smooth Porting
Port Multiple Numbers Together
If you have multiple numbers with the same carrier, port them all in one request. This is faster and less error-prone than individual ports.
Test Before You Port
Get a temporary DID from IPComms and configure your trunk first. Verify inbound and outbound calls work before porting your production number.
Configure Asterisk in Advance
Set up your inbound route for the ported number before the FOC date. Calls route correctly the moment the port completes.
Request a Specific Time
Ports typically complete in the morning. If concerned about downtime, ask your provider about scheduling a specific port time.
Asterisk Dialplan for Ported Numbers
Once your number is ported to IPComms, configure Asterisk to handle inbound calls:
extensions.conf
[from-ipcomms]
; Route inbound calls based on DID
exten => 2125551234,1,NoOp(Inbound call to ported number)
same => n,Set(CALLERID(name)=${CALLERID(name)})
same => n,Goto(internal,100,1)
; Catch-all for any DID
exten => _X.,1,NoOp(Inbound call to ${EXTEN})
same => n,Answer()
same => n,Playback(welcome)
same => n,Goto(ivr-main,s,1)
Replace 2125551234 with your ported number. See our PJSIP trunk tutorial for the full trunk configuration.
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