Hosted VoIP is a business phone service delivered over the internet. Instead of running a phone system from a box in your office, your provider runs it in secure data centres, and your team makes and takes calls on desk phones, laptops, or mobile apps.
For UK businesses, this matters now for a practical reason. The old copper phone network (the PSTN) is due to close on 31 January 2027, and Openreach has said it will not be delayed again. Any business still on analogue lines or ISDN needs a digital replacement.
This guide explains how hosted VoIP works, what it changes for your calls, and what to check before you switch.
What “Hosted” Actually Means
VoIP stands for Voice over Internet Protocol. Your voice is turned into small packets of data, sent over the internet, and turned back into sound at the other end.
“Hosted” describes where the phone system lives. A traditional PBX sits on your premises and needs hardware, wiring, and an engineer for changes. With a hosted phone system, that PBX is software run by your provider, often called a cloud PBX or cloud telephony platform.
You still have a normal-looking phone on your desk and a normal UK number. The difference is behind the scenes.
What Happens When a Call Comes In
It helps to follow one call from start to finish.
- A customer dials your number. It might be an 01, 02, 03, or 08 number, or a mobile-style number.
- The call reaches your provider’s platform. This happens over the UK telephone network and the provider’s carrier connections.
- Your call rules are applied. The system checks your settings: opening hours, an auto attendant (“press 1 for sales”), or a ring group.
- The call is delivered over the internet. It’s sent to the right IP handset, softphone app, or mobile.
- If nobody answers, the fallback rules apply. That could be voicemail sent to email, diversion to a mobile, or a second team.
All of this is controlled through a web portal. Changing the routing for a bank holiday takes minutes and doesn’t need an engineer visit.
The Four Parts of a Hosted VoIP Setup
The platform. The provider’s hosted voip London handles routing, voicemail, call recording, and reporting.
Your internet connection. Voice uses relatively little bandwidth, but it needs consistent, low-delay connectivity. Fibre broadband is the sensible baseline for most offices.
Your devices. These are usually IP desk phones, softphone apps on laptops, and mobile apps. Some older handsets can be adapted, but many analogue phones can’t.
Your numbers. In most cases you can keep your current business number through number porting, so customers never notice the change.
How Hosted VoIP Improves Everyday Business Calls
Calls Reach the Right Person First Time
Ring groups, hunt groups, and auto attendants send callers to the right team instead of a single overloaded extension. A small accountancy firm, for instance, might ring reception first, then the wider team, then a shared mobile at busy times like January tax deadlines.
Staff Stay Reachable Wherever They Work
Hybrid working is where hosted telephony earns its keep. A consultant working from home can answer the office number through an app and show the company number, rather than a personal mobile. The caller doesn’t know or care where they are.
You Can See What’s Happening
Most platforms offer call logs and reports showing missed calls, peak times, and call volumes. A dental practice that spots a pattern of missed calls at 9am can change staffing or routing to fix it. Under an old PBX, that data was often hard to get.
Growth Is Simple
Adding a user usually means assigning a licence and plugging in or installing a phone. Opening a second site doesn’t need new phone lines. This is a big reason why a cloud phone system suits small business owners who expect their team to change over time.
What Affects Call Quality
Poor-sounding calls are the most common complaint about VoIP, and they’re usually caused by the network, not the technology. Things to check:
- Router quality and settings. Many business routers can prioritise voice traffic over downloads and backups.
- Wi-Fi vs wired. Desk phones are more reliable on a wired connection.
- Shared bandwidth. Video calls, cloud backups, and large uploads can crowd out voice.
- Connection type. Fibre or a dedicated line is generally more consistent than older copper-based broadband.
A reputable provider will ask about your connection before you sign up, and may suggest a network check.
Planning for Power Cuts and Outages
Old analogue lines could keep working in a power cut. Digital voice depends on local power and a working connection. Sensible precautions include:
- A battery backup for the router
- Automatic diversion to mobile numbers if the office goes offline
- A backup connection, such as 4G or 5G, for critical sites
Before You Switch: UK Checks Worth Making
Audit your lines and devices. Phone lines are often used for more than phones: alarms, lift emergency lines, CCTV links, door entry systems, and card payment terminals. Each needs a digital replacement or a confirmed plan.
Check contract and porting terms. Ask about minimum terms, notice periods, and how long number porting takes.
Understand pricing. Costs are usually a monthly fee per user plus call charges or bundles. Compare inclusive minutes and charges for mobile, international, and 03 and 08 numbers rather than headline seat prices.
Ask about security and data. Find out where call data and recordings are stored and how GDPR is handled. If you take card payments by phone, ask how call recording interacts with PCI DSS.
Start early. Provider and engineer capacity tends to tighten as deadlines approach, so don’t leave the move until the last few months.
Providers such as Wavetel Business offer hosted telephony and can help map existing lines to digital replacements. Whoever you choose, get the migration plan in writing.
When Hosted VoIP May Not Be the Easy Option
It isn’t right for every site. Premises with weak broadband, such as some rural locations, may need a better connection or mobile failover first. Large contact centres with complex integrations may need a tailored design. A good provider will tell you this upfront.
Frequently Asked Questions
How does hosted VoIP work in simple terms?
Your calls travel over the internet to a phone system run by your provider. That system routes each call to the right handset, app, or voicemail, and you manage settings through an online portal.
Can I keep my existing business phone number?
In most cases, yes. Number porting moves your current UK number to your new provider, although timescales vary.
Do I need special equipment for a hosted IP phone system?
You need reliable broadband and either IP desk phones or softphone apps. Some older handsets can be adapted, but many analogue ones can’t.
What happens if my internet goes down?
Calls will be affected unless you have a failover. Providers can automatically divert calls to mobile numbers, and a backup connection adds further resilience.
Is hosted VoIP suitable for a very small business?
Yes. Many providers support teams of just a few people, and a hosted phone system for a small business can be more affordable than maintaining on-site equipment.
Conclusion
Hosted VoIP replaces fixed phone lines and on-site equipment with a cloud-based service that routes calls over your internet connection. For UK businesses, the benefits are practical: calls reach the right person, staff can work from anywhere, and you can see how calls are being handled.
The takeaway is to prepare before you buy. Audit your lines and devices, test your broadband, plan for outages, and compare providers on support and terms as well as price. With the PSTN closing in January 2027, starting early gives you time to move calmly rather than in a rush.