Office phone systems and VoIP for business across South Africa
Outsource Digital installs office phone systems and VoIP for businesses across South Africa. A VoIP phone system carries your calls over the internet instead of old copper lines, on desk phones, cordless phones and an app on cellphones and computers, all on the office number you keep.
You do not need to know the jargon: the sections below explain it in plain English.
Last updated October 2026
What is VoIP?
VoIP stands for voice over internet protocol. In plain English: your phone calls travel over your internet connection instead of over old copper telephone lines.
VoIP for business means your office number is no longer tied to one socket in the wall. The same number can ring on a desk phone at reception, on a cordless phone in the workshop and on an app on your cellphone, wherever you have data or Wi-Fi.
What is a cloud phone system?
Every office phone system has a switchboard. It gives each person an extension, rings the right phone, transfers calls between staff and keeps voicemail and call history. The old names for that switchboard are PBX and PABX.
In a cloud phone system the switchboard runs online instead of in a box on your office wall. Your phones and apps connect to it over the internet.
What does an office phone system include?
Desk phones, cordless phones, and the phone app on your staff's cellphones and computers, all on one system. Your number follows you to the app when you leave the desk.
We supply Yealink desk phones and cordless phones, and a phone app for Android, iPhone, Windows and Mac. Desk phones are optional: some teams work only on the app.
Phone systems for small offices and large companies
We build a phone system around your business, from a small office to a full company system.
For businesses of 1 to 10 people, the Business Bundle puts a landline number on your cellphone together with an AI receptionist, business email and a website. Larger offices get a full office phone system with extensions for every desk and department.
Can I keep my office number?
Yes. South African landline numbers can be moved between providers, so your customers keep calling the same number.
What do I need for a VoIP phone system?
An internet connection that your calls can depend on. We also install business fibre, office cabling, routers and Wi-Fi, and backup internet that takes over if your main line goes down, so one team looks after the line and the phones.
Why choose Outsource Digital for your phone system?
Outsource Digital has installed and supported office technology for South African businesses since 2004. We install your phone system, support it and fix it, across South Africa, with our head office in Midrand, Gauteng, our Nelspruit branch in Mpumalanga, and agents and support nationwide.
Existing customers WhatsApp or call 011 466 8510 to log a service call.
Phone system service and support
A technician attends within 4 to 6 business hours. Your service agreement covers on-site maintenance and remote support.
Never miss a call
Your AI receptionist answers every call your team cannot get to, in your business's name, and takes a message. With Landline to WhatsApp, customers can also WhatsApp your office landline number.
Do I have to sign a long contract?
We offer month-to-month agreements and longer-term rentals on phones and copiers.
Also useful: desk phones, mobile phone apps, AI receptionist and Landline to WhatsApp.
How it works
Your own sales executive
One person at Outsource Digital looks after your enquiry from the first WhatsApp to the installation.
A site visit
We come to your premises to see what you have and what you need.
A customised quotation
You get a quotation made for your environment, not a standard package.
Choose how to pay
Pay cash, COD, or take a rental agreement over 36, 48 or 60 months. Certain products are also available month to month. We arrange the finance for you.
Installation
We install the equipment and set it up.
Service agreement
A separate service agreement covers on-site maintenance and remote support.
What affects the cost
- The number of users.
- Desk phones, cordless phones or the app.
- The term of the agreement.
Everything can be customised. We do not publish prices: WhatsApp us and we quote on your own needs.
Questions about office phone solutions
Can I keep my existing number?
Your existing number can stay with you. South African landline numbers can be moved between providers (number porting), so your customers keep calling the number they know. When we install your new phone system, we move the number across, and it then rings on your desk phones and on the app on your cellphone.
Do my phones work during load-shedding?
A cloud system keeps running even when your office power is off. Staff can answer office calls on the mobile app. Desk phones need backup power, which we can advise on.
How much internet do I need?
Each call uses very little data, roughly 100 kilobits per second. A stable fibre line matters more than raw speed.
Can staff answer calls from home?
Yes. Staff can answer office calls from home. Office extensions work on the mobile app and on computers, anywhere with internet.
Can I add or remove extensions later?
Yes. Extensions on your office phone system can be added or removed later, without new equipment.
What is the best phone system for a small office?
The best phone system for a small office is usually a VoIP phone system that rings on desk phones and on an app on your cellphone and computer. For a business of 1 to 10 people, the Business Bundle from Outsource Digital puts a landline number on your cellphone with an AI receptionist. Bigger offices get extensions for every desk.
How much does a VoIP or cloud PBX system cost?
The cost of a VoIP phone system or cloud PBX depends on how many people need an extension, whether you want desk phones, cordless phones or only the app, whether you move your existing number, and the term of the agreement. Outsource Digital does not publish prices: WhatsApp us on 011 466 8510 for a quote.
What is the difference between a PBX and a PABX?
An office phone system's switchboard goes by both names, and in everyday use there is no difference. The switchboard gives each person an extension, rings the right phone and transfers calls between staff. PABX is simply the older name for a PBX. Today the switchboard usually runs online, as a cloud VoIP phone system.
Is PBX outdated?
The switchboard idea is not outdated: every office phone system still needs one to give extensions, ring the right phone and transfer calls. What has changed is where it runs. The old PBX box on the office wall has given way to a cloud phone system, with VoIP calls travelling over the internet to desk phones, computers and cellphones.
Can I just plug a VoIP phone into my router?
A VoIP phone plugs into your office network with a network cable, but plugging it into the router is not enough on its own: the phone must first be set up on a phone system with your number. Outsource Digital sets the phones up for you, so you plug one in and your office line rings on it.
Watch: office phone solutions in action
Missed calls mean missed business
What goes into setting up office phones
Can you WhatsApp your office landline number?
All 33 videos about office phone solutions
- "Who do I call for that?"
- Every office has loud laughers
- Which colleague would be the loudest?
- Anything except this TikTok dance
- A hosted phone system is more than just a phone
- The only guy working with the ladies
- Assembling office phones: same care for every system
- Office phone not receiving calls? A quick fix on site
- Building a new office phone system piece by piece
- Why phone system configuration matters
- Installing a wireless desk phone for a client
- What happens when your phones or Wi-Fi go down?
- How long does an office phone and Wi-Fi install take?
- An office before and after its phone installation
- Behind the scenes: office phone and Wi-Fi installation
- A Yealink desk phone with more programmable buttons
- Office Wi-Fi first, then wireless desk phones
- Wi-Fi desk phones installed for a client in Mpumalanga
- Keep your numbers and move your phones to the cloud
- Yealink entry-level IP desk phones explained
- Our stand at a golf day: Yealink phones and Toshiba printers
- Cordless office phones: the older base station and the new W73
- Proper office Wi-Fi compared with a home router
- One missed call can cost your business a client
- Upgrading office phones: Yealink desk phones and the phone app
- Your sign to upgrade your office telephone line
- Chairs, phone lines, CCTV, copiers and printers from one supplier
- We survey the site before we install a single cable
- Never miss a call again: a WhatsApp goes to every missed caller
- WhatsApp on your landline: how it works
Where we work
- Office phone solutions in Midrand and across South Africa
11 Monza Close, Kyalami Business Park, Midrand, Gauteng, 1684
- Office phone solutions in Nelspruit and Mpumalanga
Shop 6G, Riverside Auto Centre, 7 Mystic River Crescent, Riverside, Mbombela, 1200
Popular models
A few of the models we supply and install. Each has its own short page with the key features and specifications. No prices are published: WhatsApp us for a quote.
Phone system
Talk to us about office phone solutions
WhatsApp us and we will reply with the information or a quote.
Or phone 011 466 8510 (WhatsApp, opens in a new tab)
Monday to Thursday, 08:00 to 16:30; Friday, 08:00 to 15:30