Business VoIP

Extensions: the nuts and bolts of any business phone system


You may only have one main business phone number for your company, but if you employ a team of people, chances are you’ll want to be able to transfer and route calls internally between them. Phone extensions allow you to do just that – connect multiple employees to your system and assign each of them an internal number on which colleagues can reach them, completely independent of any outwardly facing numbers on your account.

If you have a landline at home, for example, you will have one ‘master’ socket in the house, and potentially one or more additional extensions that branch off that main socket. And although it’s not exactly the same thing, extensions on a phone system (whether cloud-based or not) work in a very similar way. The master socket in this example is the line (phone number) coming into your home, and the extensions are the multiple places that calls can ring and be answered internally.

How many extensions?

You will generally need an extension for every user – so if you have 10 employees, you’ll probably want 10 extensions. It’s important to note, however, you don’t need a separate extension for every device belonging to the same person. It is quite the norm with other providers to have to do that, but we allow multiple devices to register to a single extension on the basis that one person will normally want to use their extension on, say, a desk phone at the office, perhaps one at home and maybe a mobile app for when they’re out and about. Essentially, with our system each extension represents a person, not a device.

So for example, if your extension is 101, just register your laptop, smartphone and any other device you use to the same extension using the same credentials. That way, you’re always reachable by others internally on 101, regardless of where you are and on which device – they’ll all ring together, providing they’re all connected of course.

Saving money

One major benefit of an internet phone service is that calls are free between users on the same system. In effect, this gives you a really cost-effective way for your team to keep in touch. If everyone in the company has an extension, they can take that extension with them, and everyone else can call them without incurring a charge – providing they use their VoIP line to do so.

This is particularly handy if you have employees all over the world, or sales people who travel often. No matter where they are, calls to them will be free from other extensions (excluding any data charges, such as mobile phone data allowances of course).

How to add an extension

When adding a new extension, you’ll need to come up with an extension number. This is a three-digit number that is unique to the extension. This also serves as the number that other colleagues will use to call that extension.

You’ll also need to specify a name when you create a new extension. The name should ideally describe the user of the extension, and in most cases will be their own name. This is the name that will appear on colleagues’ displays when calling them internally, so try to avoid using generic names like “Extension 101”.

Once set up, you can assign an email address so that any voicemails are automatically sent to a particular place. You can also set:

  • Department
  • Outbound caller ID
  • Ring Timeout
  • Voicemail – whether it’s enabled or disabled
  • Record Calls – whether switched on or off (note that recordings are deleted after 30 days)
  • Time-based forwarding rules
  • Call waiting
  • And more…

More assistance

Extensions really are the key to getting the most from any business phone system or VoIP service such as ours. They are the building blocks that let you route calls the way you want to and provide the means to put your employees in touch with each other and your customers. If you need help setting them up, please don’t hesitate to get in touch.

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