For many small businesses, the phone system is something they rarely think about. It operates continuously in the background and requires no intervention unless an issue occurs. A missed call can quickly become a missed customer. Suddenly, a routine business tool becomes a priority.
When you need to replace your phone system quickly, it’s easy to focus on the immediate problem. This can make it harder to choose the right long-term solution. For many businesses, that means moving to a cloud phone system. It works over the internet rather than relying on traditional phone lines.
Here are seven of the most common mistakes small businesses make when choosing a cloud phone system, and what you can do to avoid them.
1. Focusing Only on Lines and Handsets
A business phone system may seem simple: a phone line and handset for each employee. It can be tempting to choose the cheapest option that covers these basic needs.
Modern VoIP (Voice over Internet Protocol) systems give businesses greater flexibility. Calls can be answered on a desk phone, a computer or a mobile app, so employees remain reachable in the office, at home or abroad. Businesses can manage call menus, voicemail, forwarding and routing on a unified communication platform, with no additional hardware required.
Before comparing providers, first consider how your business handles phone calls:
- Who answers incoming calls?
- Where should calls go when someone is busy?
- What should happen outside working hours?
- Do different teams or locations need separate phone numbers?
- How many employees may need to handle calls at the same time?
- How many regularly work away from the office?
Once you have that list, use it as your checklist when comparing phone systems. If a provider cannot meet your business’s call requirements, choosing it solely because of its low pricing may not be the most appropriate option.
2. Ignoring Additional Costs
A low monthly fee can look attractive, but it doesn’t always tell you what the service will actually cost. The final bill can include several charges that aren’t obvious from the advertised price. Some providers include additional features at no extra cost, while others charge separately for each add-on.
Before comparing providers, look at the full pricing structure and calculate the cost based on your actual usage. Check the rates for the destinations you call most, such as UK phone numbers and international numbers. Then add the per-user and per-number charges and any setup or porting fees. If your team prefers desk phones or headsets to mobile and desktop apps, include the cost of that equipment too.
It is also worth checking which features and services are included. Voice calls between colleagues may be free, while features such as call recording, voicemail-to-email or voicemail transcription may cost extra. Once you add these, a plan that looked cheaper at first can end up costing considerably more.
3. Not Planning for Future Growth
Your phone system should grow with the business. Adding new team members, opening another office or launching a customer support line should not mean going through the buying process all over again.
Before signing up, find out how easily you can scale the service as your business grows:
- Can you add or remove users yourself?
- Is there a minimum number of users?
- Does the price change with every new team member?
- How quickly can you add another phone number?
- Can you set up a number in a different UK city or another country?
Ideally, these changes should take only a few clicks in an online admin panel. The system should adapt as your business changes, and you should only pay for the services you actually use. You shouldn’t have to renegotiate the whole setup every time something changes.
4. Failing to Plan for Number Porting
If customers already know your business number, you can usually keep it when you move to a new phone system. UK businesses can generally transfer their existing numbers to a new provider, but the porting process needs to be planned in advance.
Before you cancel your current service, ask the new provider to confirm that your numbers can be transferred and what details they need from you. Providers such as Zadarma support UK number porting, so check their requirements and process before you begin the switch.
Complete the required authorisation and agree on a transfer date. Keep your old service running until the number has been transferred and you have tested the new service. This helps avoid unnecessary disruption during the switch.
5. Overlooking Automation
A business phone system is no longer just about answering and transferring calls. Modern systems can automate some of the routine work that used to take up employees’ time.
For example, AI voice agents can handle common customer enquiries, while automated call routing directs callers to the right person or team. CRM integrations link each call to the customer’s records. Auto diallers let sales teams make high volumes of calls without dialling each number by hand. Providers such as Zadarma now offer these features alongside traditional phone services.
Start by looking at where your team’s time actually goes. If your employees regularly answer the same questions, take down caller details, log call details in a CRM or make repetitive outbound calls, part of that work can be automated.
That said, automation is only worth introducing where it solves a real problem. Focus on the tasks that consume the most time and consider whether automating them would actually help your team. Paying for features your team will never use adds unnecessary cost.
6. Not Considering Internet Reliability
With a cloud phone system, your internet connection becomes part of your phone system. If the connection is slow or unreliable, call quality can suffer even when the phone service itself is working normally.
Before switching, make sure your internet connection can handle the number of calls your team expects to make or receive at the same time. It should also have enough capacity for other activities happening on your network.
Where possible, use a stable network connection and make sure your network can prioritise voice traffic. This can help prevent downloads and other heavy network activity from affecting call quality.
You should also consider how the system will perform during an outage. Many cloud phone systems can redirect calls to mobile phones or let employees continue taking calls through an app. Some providers, such as Zadarma, also offer eSIMs that can provide a backup internet connection when the main connection is unavailable.
This is becoming increasingly relevant in the UK as the Public Switched Telephone Network (PSTN) is being switched off on 31 January 2027. Businesses still using traditional phone lines need to plan their move to a digital alternative and consider their internet connection and power supply when setting up their phone system
7. Overlooking Customer Support
When choosing a new phone system, most businesses focus on price, features and technology. Support is easy to overlook, yet it matters just as much. If your phones stop working, you need to know you can reach someone who will help you fix the problem quickly.
Before choosing a provider, check how its support works in practice. How can you contact the support team? When is support available? How quickly do they normally respond? One simple test is to contact the provider before you buy. Their response will show you how quickly they reply and how useful their answers are, before you sign up.
Good support may not seem important when everything is working normally. But when your phones stop working on a Monday morning, it can be just as important as the phone system itself.
Taking the Time to Choose the Right System
A business phone system needs to do more than meet your needs today. Choose one that fits the way your business works now and can adapt as it grows and changes. Comparing providers carefully, understanding the full costs and thinking through how the system will work day to day can save you from having to replace it again in a few years.
Independent reviews and industry awards can also help you narrow down a shortlist. The Comms Council UK Awards, for example, recognise UK VoIP and unified communications providers each year. Smartvoice, the UK company behind Zadarma, was shortlisted in the Best Comms Provider Mid Market category in 2026.
A good phone system should support your business without becoming another problem to manage.
