In this guide
Short answer: VoIP, or Voice over Internet Protocol, makes phone calls over your broadband instead of over a copper phone line. You keep a normal phone and, usually, your number. It needs power and a stable internet connection, but it offers more features and flexibility, and it is where all UK landlines are heading.
You may have heard VoIP mentioned in connection with the UK landline switch-off, or by a business offering cheaper calls. The name sounds technical, but the idea is simple, and it is probably already part of your life if you have ever used WhatsApp or Teams to make a call.
How VoIP works
- You speak into a phone, an app or a computer.
- Your voice is turned into digital data and split into small packets.
- The packets travel over your internet connection to your VoIP provider.
- The provider connects the call to the person you are ringing, whether on another VoIP service, a mobile or a traditional landline.
- The reverse happens for the voice coming back.
The set of rules that sets up and manages the call is called SIP, which you will often see in VoIP phone settings.
What do you need?
- A broadband connection. It does not need to be very fast, but it must be stable.
- A handset. A SIP desk phone, a cordless phone with an adapter, or an app on your mobile or computer.
- A VoIP provider. This supplies your number and connects your calls.
- A router that handles voice properly. Voice traffic should be prioritised so calls do not break up when the connection is busy.
How much bandwidth does it use?
Less than most people expect. A single call uses roughly 80 to 100 kbps in each direction. What matters far more than headline speed is a connection with low delay and little loss, because voice is sensitive to a bumpy connection.
VoIP versus a traditional landline
| Feature | Traditional landline | VoIP |
|---|---|---|
| Runs over | Copper phone line | Broadband |
| Works in a power cut | Yes | Not without a battery backup |
| Number | Tied to the line | Portable between providers |
| Extra features | Limited | Voicemail to email, forwarding, call groups, apps |
| Handsets | Any standard phone | SIP phones, or standard phones with an adapter |
What VoIP offers homes
For most homes, VoIP is simply the new way of having a landline. You keep a normal phone, and calls to UK landlines and mobiles are often included in the plan. It makes more sense now than ever, because the old network is being retired; our guide to the 2027 landline switch-off explains what to do.
What VoIP offers small businesses
- Several extensions on one number.
- Hunt groups that ring a team in order.
- An auto-attendant greeting, such as press 1 for sales.
- Voicemail sent to email.
- Calls that follow you to a mobile or a laptop.
- A local number, such as 01702 in Southend or 01245 in Chelmsford.
Things to know
- Power cuts. A VoIP phone needs the router and handset to be powered. Use a battery backup and keep a charged mobile.
- Emergency calls. 999 works, but your registered address must be right so help can find you.
- Call quality. Voice needs a stable connection. Wired phones and proper router settings prevent most problems.
Keeping your number
You can usually move your existing number to a VoIP provider. Read how to keep your landline number for the steps, and how to fix VoIP call quality problems if calls ever crackle or drop.
HomeIT Services supplies and sets up VoIP for homes and small businesses across Essex, with handsets, routers and numbers all configured. See VoIP phone systems and digital landline setup, or contact us from Chelmsford, Southend-on-Sea or nearby.
Frequently asked questions
It does the same job, but calls travel over your broadband instead of a copper phone line. You can keep your number and use a normal-looking phone.
Yes. VoIP needs an internet connection, and call quality depends on its stability, not only its speed.
Yes. UK VoIP providers must support emergency calls, but the call needs power and an internet connection, so have a charged mobile as a backup.
A single call typically uses roughly 80 to 100 kbps each way, so even a modest connection can handle several calls at once.
Yes. Features such as extensions, hunt groups, voicemail to email, an auto-attendant and mobile apps make it a flexible replacement for older business lines.
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