By alicia.sandino on May 23, 2017
Hardware & Technology

Traditional phone systems have made us think about phone lines and extensions as fixed entities; a phone extension is an internal number (usually four digits) that employees dial to reach one another and if a call comes in from an outside line, they would need to dial a different number to reach someone.

Adding phone numbers and connecting phone lines caused monthly phone bills to increase as businesses grew. If the company grew to multiple locations, even

If the company grew to multiple locations, even more phone numbers were needed and extra phone lines had to be installed.

Although this wouldn’t prevent business growth, it could put a damper on businesses needing more phone lines but not wanting to pay extra costs.

VoIP’s emerging technology has offered multiple functionalities that have improved the way businesses communicate.

So, what is a phone extension? Extensions are not “lines,” as they are commonly known as.

When it comes to VoIP, extensions are end points where you can make or receive calls, allowing you to easily organize your call flow as your business grows. You don’t have to have a different phone number for every employee; you can assign each employee an extension so when your business receives a call, the caller can dial an extension to be routed to the person they need.

With traditional phones you would not be able to call one phone number and reach multiple people or devices; with VoIP, you can do just that.

Here are some examples of a phone extension with VoIP:

  • When call forwarding is implemented, dialing an extension can prompt the caller to be directed to your mobile device.
  • You can reach individuals in a conference room by picking up your desk phone and dialing the extension number that directs you to the conference room phone.
  • Dialing an extension can direct someone to VoIP software on your phone, also known as a soft phone, which can be accessed via an app.
  • The most common use of a phone extension is reaching you at your desk phone by pressing a predetermined set of numbers

Analog Extension vs. VoIP Extension

To break down the bigger picture here are some key differences between analog and VoIP extensions.

With analog, or premise-based solutions, you have to pay per line and roll over numbers (a.k.a. call waiting) is required. Busy signals can be problematic especially for new businesses and are inevitable unless you have enough roll over numbers.

On the other hand, when you’re using VoIP, an extension can be directed to any and all end points (apps, external lines, etc.) without needing an extra phone number and it won’t tie up your phone lines.

An extension is not fixed to a phone line; it is its own entity so you can have one main business phone number with dozens of extensions pointing to different people in different geographical locations.

A VoIP Phone Extension Does Much More

It’s obvious that an extension with VoIP is much more advanced than a traditional extension. The capabilities are easily accessible and user-friendly. To give you even more insight on its usability, here’s a list of ways you can use your VoIP phone extension.

  • Automatically operates with VoIP phones
  • Put people on hold
  • Auto direct dialing
  • Take multiple calls at the same time
  • Conference calling
  • Call forwarding
  • Take your extension with you, either by using your mobile device or taking the physical desk phone and plugging it in to your new destination
  • Transfer calls internally
  • Virtually unlimited extensions per phone number
  • Make and receive calls from your business phone number from any device
  • If you’re directing business calls to your mobile device, you can use a pass through caller id or call confirmation to differentiate a business call from a personal call


Ready to enjoy VoIP phone extensions to their fullest potential? Get in touch with a FastPBX cloud specialist and start optimizing your business communications.

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A Month

  • 1,000 Minutes Per Month
  • Go Mobile
  • 2 Local Numbers
  • Unlimited Extensions
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A Month / Per Extension

  • Unlimited Minutes
  • Use Desktop Phone or App
  • Choose / Bring Your Numbers
  • Simultaneous Ringing
  • Paging
  • Voicemail to Email
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A Month / Per Extension

  • Unlimited Minutes
  • Use Desktop Phone or App
  • Choose / Bring Your Numbers
  • Auto Attendant
  • Conference Calling
  • Call Logging
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A Month / Per Extension

  • Unlimited Minutes
  • Use Desktop Phone or App
  • Choose / Bring Your Numbers
  • Call Analytics
  • Call Recording
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