Businesses often want to place outbound calls from phone numbers their customers already recognize. In some cases, that means keeping an existing number with another provider. In others, it means fully moving that number into a new platform.

SignalWire supports both paths:

• Verified Caller ID, which lets you use an existing number for outbound calls without porting it

• Local Number Portability (LNP), which transfers full ownership of a number into SignalWire

Understanding the difference helps you choose the right option for your calling workflow.

What is verified caller ID?

Verified caller ID allows you to use a phone number you already own as the outbound caller ID for calls placed through SignalWire.

Instead of porting the number, you verify ownership by completing a short verification process. Once verified, SignalWire allows that number to be used as the “From” value on outbound voice calls.

This option is useful when:

• You already have a number with another carrier

• You only need the number for outbound calling

• You do not want to move inbound service or messaging

Verified Caller ID is outbound-only and does not transfer the number’s service.

How verified caller ID works

The verification process confirms that you control the phone number:

1. You submit the phone number in the SignalWire dashboard

2. SignalWire places an automated call to that number

3. You enter the verification code provided during the call

4. The number becomes eligible for outbound caller ID use

Once verified, the number can be used for outbound calls from SignalWire without changing its existing carrier or service.

What is local number portability (LNP)?

Local Number Portability allows you to fully move an existing phone number from another carrier into SignalWire.

When a number is ported:

• SignalWire becomes the service provider for that number

• The number can be used for inbound calls

• The number can be used for outbound calls

• Messaging services can be enabled

• Call routing and automation can be applied

Porting is the right choice when you want full control over how a number behaves.

Verified caller ID vs porting a number

While both options let you call from a familiar number, they serve different purposes.

Verified Caller ID:

• Outbound calls only

• No inbound calling

• No messaging

• Faster setup

• Number remains with the original carrier

Ported number:

• Inbound and outbound calling

• Messaging support

• Full routing and automation

• Complete platform control

• Number service fully moves to SignalWire

Choosing between them depends on whether you need full telecom functionality or just outbound caller identification.

When to use verified caller ID

Verified caller ID is best suited for:

• Outbound sales or support calls

• Temporary campaigns

• Gradual platform migrations

• Situations where inbound calls remain with another provider

It allows teams to start calling immediately without waiting for a porting process.

When to port a phone number

Porting is recommended when:

• You want inbound calls handled by SignalWire

• You need SMS or MMS on the same number

• You want programmable routing, IVR, or automation

• You are consolidating telecom infrastructure

Ported numbers behave like native SignalWire numbers.

Compliance and trust considerations

Using verified or ported numbers helps:

• Maintain consistent caller identity

• Reduce call blocking from carriers

• Improve answer rates by using recognizable numbers

• Align with caller ID authentication frameworks

SignalWire enforces verification and ownership checks to prevent spoofing and misuse.

Getting started

You can:

• Verify an existing number for outbound calling in the SignalWire dashboard

• Initiate a port request to bring a number fully into SignalWire

Both options are designed to support legitimate business calling while preserving flexibility.

Then, bring any questions to our community on Discord.

Frequently asked questions

What is Verified Caller ID?
Verified Caller ID lets you use an existing phone number you already own as the caller ID for outbound calls through SignalWire by proving ownership via a verification process.

How do I verify my existing phone number with SignalWire?
In your SignalWire Dashboard, go to Phone Numbers → Verified, click Verify a Phone Number, enter the number, and complete the verification code you receive via a call to that number.

What is Local Number Portability (LNP)?
Local Number Portability lets you keep your existing phone number when moving to a new telecom provider or platform, such as bringing it into SignalWire, without changing the number.

What’s the difference between Verified Caller ID and porting a number?
Verified Caller ID allows outbound caller ID without moving the number’s service, while porting fully transfers the number into SignalWire so it can be used with all SignalWire services such as incoming calls, SMS, and full outbound use.

Why would I want to port my phone number instead of just verifying it?
Porting gives you access to the full suite of SignalWire services for that number, including inbound traffic and messaging, while Verified Caller ID only covers outbound caller ID without moving the service.