As your business grows, you’ll take on more staff who need to communicate internally. You’ll also generate more customers, suppliers, and contacts who need to get in touch with you. If you have a completely different phone number for every employee—or even every department—it’s going to get pretty confusing.
This is where extension numbers come in. By adding them to your main phone number, you’ll make life easier for your staff and external callers alike (and there are plenty of other business benefits, too).
But what exactly do we mean by “extension number”, how do you set them up, and how do you call one?
What is an extension number?
So, what’s an extension number? It’s a short numerical code, a few digits long, that’s added to the end of a regular phone number.
These extensions are assigned to different subdivisions or people within an organization. When someone dials an extension, it takes them straight to the individual or department they need.
Business vs. residential extensions
Businesses often have multiple extensions which they assign to employees, teams, or departments. This provides a handy shortcut, both for people within the organization and those calling from outside it.
Those types of business extensions enable multiple users to talk on the same line at the same time, and receptionists or operators to quickly transfer calls between departments and colleagues.
With residential extensions, a single phone line connects multiple devices in different rooms, but they don’t have their own codes.
When someone calls your main number, all connected devices will ring. You can receive and make calls from any device, and other residents can join a call from another room. But, unlike business extensions, the line will be busy even if only one extension is in use.
Extensions vs. virtual phone numbers
We now know what’s meant by an extension number, but how does that compare to a virtual number?
There are similarities, in that neither type is tied to a specific location or device.
Phone extensions are short additions to a main phone number, but virtual numbers are complete phone numbers in their own right.
To set up a virtual number, you’ll typically need a VoIP phone system that operates over the internet, while extensions can work with a traditional PBX system (although switching to VoIP gives you far more benefits, too).
Virtual numbers can also be known as Direct Inward Dialing (DID) or direct-dial numbers. You can typically set them up in the same place where you manage all your phone numbers. Here’s how that looks in Dialpad:
How does an extension number work?
When you use phone extensions, your main phone line is split into branches, and each is assigned its own code. This means that multiple people can use the line at the same time, without the need to install additional physical lines.
In a business with several departments, you could assign a phone extension number to each one. For example, you might assign 01 for sales, 02 for accounts, and 03 for support. (Traditionally, all extension numbers had four digits, but alternative lengths are now available.)
You can also assign extensions for individual employees. If you want to denote which department they work in, you could combine their codes with department codes—so Bob in sales might be 01-123, and Kris in accounts might be 02-234.
Some businesses use extensions just for internal use, especially in large companies with many employees. In this case, people only need to dial a colleague’s extension code, not the full business phone number. The system is programmed to recognize the code and route the call to the right place.
You can also give extensions out to external callers, to help them reach who they need. When they call, they’ll be prompted to enter the relevant extension. It’s possible to direct incoming calls to a single phone, multiple phones, auto-attendants, or voicemail.
If you have a VoIP or unified communications system, you can manage extensions by logging into your online dashboard and selecting the option to add, edit, or remove a user.
Here’s how that looks in Dialpad:
With smart call routing (like you get with Dialpad), you can set up a phone tree with rules for what happens when someone calls an extension, internally or from outside. If the extension is connected to more than one device, you can have the system forward the call to all the devices. For extensions covering a whole team or department, the system can distribute calls among the employees either simultaneously, in a cycle, or in a designated order.
Or, you could route them to the manager first. What happens if a call goes unanswered—will you route it back to the auto-attendant, try another department, or offer a voicemail option?
DID YOU KNOW?
If you have several offices in different geographical locations, you can still use extension numbers to call between them. You’ll need a unified communications system or collaboration platform to set this up, though.
How do you call an extension number?
Calling an extension number couldn’t be easier. Here’s how to call an extension number in the UK. For these examples, we’ll use the UK phone number format and imagine your business phone number is 0123 456 7890.
To reach a colleague or internal business department
If you’re calling from inside the business, you don’t need the full business number. Let’s say you work in marketing, and you want to get hold of the accounts team. Using the example from the previous section, the accounts department has the extension 02. Simply dial 02 from your office or VoIP phone.
If you want to speak to a specific colleague, you’ll need their personal extension. Sticking with our example, that’s 02-234 for Kris in accounts. Other members of the accounts team can reach Kris just by dialing 234—even if they work in a different office.
As a customer or outside caller wanting to speak to an individual or specific department
Now we’ll show you how to use an extension number from outside the business. In this case, you’ll need to dial the main company phone number first. If the company has set up a directory or phone tree of extensions, you’ll hear a recorded message asking you to dial the relevant code.
If you already know that the accounts department is 02, dial the code now and you’ll be put through. Key in 02-234 if you specifically want to reach Kris. If you don’t know the extensions, the system may place you in a queue to speak to a human who can direct the call to the right place.
Or, the business may have an automated IVR menu to take you through the options and route your call. You can set that up in Dialpad (in any language you like):
Benefits of extension numbers for your business
Extension numbers bring many advantages to your business, from enhanced efficiency to serious cost savings. Let’s take a look:
Improved employee experience: With extensions, it’s much easier for employees to contact each other or transfer incoming calls. They don’t have to remember full-length phone numbers for each colleague. Plus, because extensions aren’t tied to a specific location, this opens up the possibility of remote, flexible working.
Improved customer experience: It’s also easier for customers, who can use extension codes to go straight to the right person or department. They don’t have to waste time in queues or explain what they want to a receptionist. And for client-facing team members, giving a client your personal code is one way to establish a relationship and make them feel valued.
Increased productivity: Extension numbers (coupled with efficient routing) can save a lot of time for a business. They offer a fast self-service option to external callers, which means you can handle more calls in a day.
Accuracy also improves, as the short and simple codes significantly reduce errors in transferring calls. (Some communications solutions like Dialpad also have a click-to-dial feature, so you don’t even have to key in the code.)Cost savings: Apart from the improvement in efficiency, it’s more affordable (and less hassle) to add extensions to your system than new physical phone lines. You can even connect other office locations or remote teams via extensions.
Enables data analysis: Using extensions helps you to analyze call patterns and spot opportunities for improvement or further savings. For example, if calls to a certain extension have a higher than average hold time, you can look into the issue and maybe decide to add more staff to handle incoming calls.
Enables campaign testing: Marketing teams can use specific extension numbers to evaluate the performance of campaigns and individual ads. If a certain ad contains a dedicated extension number for interested parties to call, a high volume of calls to that code means the ad is working. Or, you could run an A/B test to discover which version of an ad works best, by placing a different extension on each ad and tracking the calls.
Boosts scalability: Phone extensions are ideal for companies with a large number of employees and departments, and for firms that expect to grow in the near future. You can add as many extensions as you wish, and continue to use them if you expand into new regions.
DIALPAD TIP:
You can use extensions in conjunction with virtual phone numbers to localize your business. To attract customers in a new area, you might choose a virtual phone number with a local area code, so people in that area trust calls from your company. Add extensions, and these new customers can reach your individual staff and departments back at HQ.
Harness the benefits of extension numbers on the Dialpad Enterprise plan
If you’re on the Dialpad Enterprise plan, you’ll get phone extensions as standard. It’s super easy to set these up via your online dashboard, in just a few clicks. You can create new users and assign phone number extensions, or assign new extensions to existing users.
If you need to edit or delete them, that’s simple, too. That’s because Dialpad is designed to be easy to manage with minimal help from IT. (Although, if you do need a hand, Enterprise customers can always access priority support).
The platform also has an IVR feature, which you can program to help callers find the right extension number—or anything else they need to know. Smart routing options include skill level, idle time, and round-robin style.
As a holistic collaboration platform, Dialpad gives you video calls, team messaging, integrations, and more in addition to HD voice calls. The built-in Ai can transcribe calls in real time and perform live sentiment analysis, plus you can access local and vanity numbers to use alongside your extensions.