Best business VoIP provider (UK)
Based on our in-depth, expert analysis, independent reviews, awards and service levels, we found that the following companies are currently the best UK VoIP providers for businesses:
- Gamma
- 3CX
- Mitel
- RingCentral
- 8x8
- bOnline
- Vonage Business
- 4Com
- Gradwell
- Lily Comms
- BT
- Virgin
- SureVoIP
- Microsoft Teams
The top five UK VoIP providers in March 2023

Short for Voice Over Internet Protocol, VoIP means that telephone calls are made through the internet, rather than a landline, ISDN, or mobile network. A VoIP phone system gives businesses lots of additional functionality to make phone calls. Examples include call recording, call transfer, hunt groups, and even the ability to make calls from mobile phones.
The two types of VoIP systems
There are two ways you can get a business VoIP system; buy the equipment and run it from your office, or subscribe to a hosted VoIP provider, like the UK VoIP providers mentioned in this guide. In 99% of cases today, the latter is the best solution for businesses for various reasons such as reliability and cost. For that reason, in this article, we will focus on hosted VoIP phone systems.
A VoIP phone system works by taking your analogue voice signal and converting it into a digital signal that can be transferred over a broadband line to your UK VoIP Provider.
Unlike traditional phone systems where you need a physical phone, you could use any of the following to make VoIP calls:
- A VoIP Phone
- A computer with an internet connection
- A smartphone with an internet connection
- A web browser (with some VoIP phone systems)
How VoIP works with an IP phone:

How VoIP works with a laptop softphone:

Regardless of the business VoIP provider you choose; there are some universal benefits you can expect to enjoy:
- Lower service costs
- Work from anywhere with an internet connection
- Free calls - near unlimited calling
- Improved portability
- Scalability
- Advanced features
- Clearer voice quality
- Flexibility with softphones and mobile apps
- Easy to manage via a web portal
Lower costs
Controlling costs in business is vital, which is why the first benefit of VoIP phone systems we want to bring to your attention is that, in most cases, it lowers costs. Of course, how much it reduces costs depends on your current systems, but we would usually expect savings of anywhere up to 50%. Yes, that's right, VoIP services can save you up to 50% compared to a traditional phone system with an ISDN line.
Cost savings vs a traditional PBX
When it comes to a traditional phone system, businesses must invest in handsets and PBX hardware. A PBX on its own can cost thousands of pounds, and while that can often be leased over several years, getting set up still represents a massive cost.
In contrast, by using a cloud-VoIP provider, you do away with the capital outlay and simply charge you per user per month for everything.
Connectivity costs
To run a traditional phone system before VoIP, you needed telephone lines such as ISDN and internal cabling to every desk. Every time you want to add another person to the system, you'd need to get them connected via a cable running back to the PBX; this is, of course, in addition to any networking you need for computers. The great thing with business VoIP systems and handsets is that they run over the same network as your computers, completely removing the need to have a second connection going back to your comms room. Not only that, but they can also even run over wireless, which, while not quite as reliable as a physical network cable, can give you more flexibility over where the handset is located in the office. Finally, as we know, ISDN line rental is costly and is being phased out in favour of SIP lines - by moving to VoIP, all of your calls go over your internet connection so you can rid yourself of one more ongoing cost.
Call costs
Direct savings also come in the form of reduced call costs, with many VoIP service providers even offering substantial free call packages; our favoured options, for instance, give you 2000 minutes to UK landlines and 2000 minutes to UK mobiles per user per month! VoIP calls can be up to 60% cheaper domestically and sometimes up to 90% cheaper internationally than calls via PSTN or ISDN.
Maintenance costs
Another significant cost related to traditional phone systems and handsets is the maintenance costs. When you purchase a PBX, you'll invariably take out a support service alongside it with a local provider so that as or when you have issues or want to make changes, you have someone to call. Those maintenance costs add up, and as your system gets older, you'll likely find that the support fees only increase.
By getting a hosted VoIP system, you remove the need for a maintenance contract to support your PBX. You pay your monthly fee per phone, and the rest is taken care of. You don't own the hardware and therefore don't need to look after it.
Work from anywhere
Arguably one of the most significant benefits given that we are increasingly working from both the office and home is the ability to take business calls anywhere you have an internet connection. With VoIP, you aren't tied to a physical phone line, so you can be anywhere in the world and pick up your business phone. This flexibility is a massive benefit for businesses that embrace home working and hybrid working following the pandemic.
Improved portability
A VoIP number is completely portable, so you can use the same number wherever you go. For people who travel often, this is welcome news as they can appear to be in the office from anywhere. Better yet, if your business changes its address or your employees need to work from home for an extended period, you can all keep your phone numbers; it makes things seamless.
Scalability
Scalability is a benefit often associated with VoIP as it provides business owners with a system that can grow as their company grows. A cloud VoIP solution does away with the need to purchase expensive hardware or a dedicated telephone line as a business grows. Got a new office opening? Simply order a few more handsets and ship them to the site.
Advanced features
VoIP provides you with many advanced features such as auto-attendant and call forwarding that help businesses of all sizes operate efficiently and help small companies project a larger image. Equally, VoIP can help large enterprise-scale organisations present a more approachable image. It all comes down to how the VoIP system is set up.
Let's say you have a Birmingham-based business, which serves clients across the UK, but especially in London. By signing up with a business VoIP provider in the UK, you can get a VoIP phone number with a London area code, even though you're not based there. This gives your customers the impression that you're a local business even though you might not be.
Similarly, the auto-attendant and call routing features can make you look larger than you are. For example, you could be a sole trader, but you've set up your VoIP system to seem like you're a company with several departments.
Clearer voice quality
Today, as long as you have a fast and stable internet connection, voice quality shouldn't be an issue. VoIP calls tend to be clear and crisp, with no latency, lag or call dropout issues.
The key to VoIP call quality is having broadband or a reliable leased line with plenty of bandwidth. If your connection is slow and often drops, it's a warning sign that VoIP might not be the right fit for your business.
Two lines are better than one
At T2k, we typically recommend you should have one internet connection for your VoIP phone service and another for your computers. This separation ensures that employee internet usage doesn't impact your phone calls. If you choose a VoIP service provider who does both phone services and broadband, the other plus is that your calls have less "digital distance" to travel, improving reliability and giving you the best call quality.
Unified Communications refers to a VoIP phone system that integrates multiple communication methods. A business usually communicates in many ways, such as phone calls, video conferencing, instant messaging, email, SMS, fax, etc. A Unified Communications service connects many of the ways your business communicates, letting them talk to each other in one system and making your business more efficient. The best UK VoIP providers and their systems will typically enable companies to utilise the power of Unified Communications.
Whom you choose to provide your VoIP is incredibly important, given that, in all likelihood, you'll be with them for several years. Ofcom offers several tips on things to ask when choosing a VoIP provider, but our thoughts are that you need to make sure they offer all of the following:
- Setup for minimal or no capital outlay
- The choice between hosted or an onsite solution
- UK based customer support
- Highly rated and reviewed
- In business for a reasonable length of time
- A clear track record for high service levels
- Experienced with small and large business
- Lots of features that match your requirements
Without further ado, we bring you our summarised list and reviews of the best UK VoIP providers for businesses in 2023.
Please remember that the best VoIP provider for you will largely depend on your requirements, so it's always best to speak to us first to help you make the right choice.
You can reach us on 01202 854111, Monday to Friday, 8:30 am-5:00 pm. Alternatively, click one of the buttons on this page to request a comparison quote.

Cloud-based VoIP platforms today provide a complete business communications service with extensive fixed and mobile telephony capabilities.
What to look for in a VoIP phone system
When you're changing your phone system, you want to ensure that whatever you move to won't just save you money but give you a reliable platform for growth. You want to maximise productivity and give your team the tools they need to provide brilliant customer service. Business-focused features that emphasise control and administration take the burden of management away from you and improve profitability.
In our opinion, you should always look for a UK VoIP provider with exemplary support, as your phones are central to the performance of your business.
Find a system with an easy to use interface
Most, but not all of the top providers, will give you a web portal where you can log in and manage your phone system. Here are some of the options you'll have:
- Call history
- Voicemail to email settings
- Call routing management
- Hunt Group configuration
- Call Recording settings and the recordings themselves
- Call stats, reports and dashboard
Features that improve team working
Cloud VoIP improves team working through a variety of features; many of which should be included as standard with your VoIP system's subscription:
1) Adhoc conferencing
Start a conference at any time, without scheduling a meeting, simply drag and drop users from your contacts to an open within, and you can enjoy all of the features of a planned conference.
2 ) Hunt Groups
Distribute calls across your team using Hunt Groups; it doesn't matter where the team is based, or even if they're in the same office; if they're in a group and available, they can be included in your call routing. Choose from the following five ways to call the group:
- Circular - Sends calls to users based on their position in a list
- Regular - Sends calls to the next available user in the hunt group
- Simultaneous - Sends incoming calls to all of the users at the same time
- Uniform - Send the call to the user who has been idle the longest
- Weighted - Assigns calls to users based on percentages you set in the Hunt Group
3 ) Call transfer
Transfer calls to any internal or external number quickly and easily, and not only that, easily receive the call back if no one answers. Simply enable the settings, and you'll have the option of how many times a transferred call should ring before it's transferred back to you. You don't need to answer either; using Blind Transfer, you can transfer a call without speaking to the person.
4 ) Common or customisable settings for sites, groups and departments
Reduce admin and maintain consistency across the organisation by grouping sites, teams and departments together. Changes in settings can then be rolled out on a per-site, team or department basis.
5) Call park
Put a call on hold and pick up another phone, giving you the flexibility to move around the office and even switch to a mobile device or computer.
6) Call Pick-up
Is someone in the team away from their desk? With Call Pick-Up, you can take the call and tell the person when your colleague will be back. This feature allows you to answer colleagues' phones and pick up call-waiting calls.
7) Call Waiting and music on hold
Call waiting for queued callers and ensure you're ready to take the next call. With music on hold, you can choose to play waiting music or even promotional messages while your customers wait.
8) Auto Attendant
Auto-attendant provides menu options to callers so that their call can be routed to the correct person or team. You can create a bespoke schedule that enables the auto-attendant only during working hours and disables it when the office is closed for a holiday.
Features to improve efficiency
VoIP phone systems provide a range of features specifically designed to help your team maximise their efficiency.
1) Last number redial and click to dial
Quickly redial the last number that was called, received or missed and use your computer to Click to Dial anyone in your contacts list.
2) Presence or Pre-set Availability
Manage incoming calls with Presence and Pre-set Availability; if you know you're not going to be available, your business phone needn't ring. Call routing can take the caller to someone available. Choose from four different availability profiles:
- Available In Office
- Available - Out of office
- Busy
- Unavailable
These profiles include the ability to manage incoming call functions, for example, Call Forwarding, Busy, Voice Messaging and Call Notify.
3) Anonymous call Rejection or Selective call Rejections
Anonymous Call Reject allows a user to reject calls from people that have restricted their caller ID. By activating the service via your provider's web portal, callers without identification will be informed that the user isn't accepting calls. The user's phone won't ring, and the user won't see or hear any indication that a call was attempted. This service, of course, doesn't apply to calls from within the business or group.
4) Auto Call Back and Busy Lamp Keys
If you call another person in your company and are busy, you can use Automatic Call Back to be notified when they're off the phone. Equally, you can have Busy Lamp Keys on your phone handset, which show you whether another user is on a call or not.
5) Do Not Disturb
Do Not Disturb will show you're unavailable and automatically reject attempted calls or transfers.
6) Company Directory
With Company Directory, you can assign up to 100-speed dials for your favourite numbers. Save time and avoid having to search for a popular number.
7) Call Recording
Use call recording to create audit trails and ensure compliance. Equally, you can use call recording for training purposes and quickly and easily listen back to calls that have taken place.
Mobile and flexible working
VoIP services give you and your team so much flexibility to work from anywhere. Enjoy features such as Call Forwarding to manage calls effectively, Home Worker to take profiles and settings home, Voicemail to email to never miss an important call, and Hot desking to move around and work from anywhere.
The phones you get for your new VoIP phone system play a big part in your team's experience. VoIP phones come in all shapes and sizes, but one thing to bear in mind is that not all phones will work with all UK VoIP Providers' systems. While we can show you some of the best handsets on the market, it's always wise to speak to your VoIP provider to find out what they offer.
Poly VVX 150 Phone
The Poly VVX 150 handset is an entry-level phone suitable for handling low to moderate call volumes. With an intuitive user interface, usability and navigation are simple, requiring minimal training. The VVX 150 provides a high-quality but cost-effective solution with advanced unified communications (UC) features.
Poly VVX 250 Phone
The Poly VVX 250 iis a basic VoIP phone with a colour display. It's a high-quality IP phone with four lines and excellent sound quality. It's ideal for office workers who need the quality features that a modern business environment demands.
With Polycom HD Voice delivering superior high definition sound quality, the VVX 250 has advanced voice processing capabilities.
Poly VVX 450 Phone
The Poly VVX 450 is a step up from the previous models featuring 12 lines and is a high-performance desk phone with a colour display. It's a high-quality IP phone stacked with features for today's busy business executives and upper management. It's a perfect fit for all environments, with the HD Voice delivering superior sound quality. The Polycom Acoustic Fence technology minimises background noises, echoes and distractions.
Yealink W52P Cordless
The Yealink W25P Cordless IP Phone is the perfect fit for busy small businesses that need a flexible device that can roam around an office. In our experience, the Yealink W25P is the best wireless business VoIP phone currently available, feature-rich and cost-effective, the perfect companion to cloud-based VoIP services.
PolyTrio 8500 Conference Phone
The Poly Trio 8500 takes business conference calling to the next level. It's a sleek and sophisticated model with a full-colour screen for ease of navigation and use. With Polycom's market-leading voice quality, you can be sure that your meetings will be seamless.
Poly Trio 8800 Conference Phone
The PolyTrio 8800 is a modern business conference phone with video and content performance that marries excellent voice quality. The Polycom Trio can turn meeting rooms into a collaborative, hassle-free team working environment.
It can be challenging to know their differences with hundreds of UK VoIP providers to choose from. This section gives you our top tips to consider when you're choosing your VoIP provider. Click here if you'd like a more detailed guide to choosing a business VoIP system.
Price of business VoIP services
Prices between business VoIP providers can vary quite significantly, so it's essential to get several quotes to understand what they will charge you per month.
Work out how many minutes you use approximately per month and then see if it's worth paying a set fee for a certain number of minutes, or would it be less expensive with a pay-as-you-go VoIP provider?
Spending an hour researching the options will ultimately save you a lot of money on calls.
Quality of business calls
We always recommend researching the business VoIP providers you're speaking to understand their customers' thoughts.
Business VoIP services require a significant amount of investment to keep them operational, so you need to know that you're in safe hands as a customer.
Ease of use of the VoIP platform
Some VoIP providers will provide you with complicated instructions that are difficult to follow and make using the system a real struggle. Others will install for you and be on hand to give you training on how to use the system. Look for a provider that offers you that level of customer service as you must have got a good grasp of the system.
If you're pretty technical already, this may not be too important to you, but the simpler, the better for everyone else.
Choose a business provider for the features you'll use
The functionality that business VoIP systems provide is far greater than you'd expect from a traditional phone or even a PBX system; because of that, you'll want to make sure you familiarise yourself with all of the things the cloud-based platforms you're looking at can do.
While many of these features will be included in your monthly service fee, some will attract an additional charge, so speaking to each provider to establish what it'll cost for you to use such features is essential.
Can you scale the service up and down?
VoIP allows your business to connect your staff quicker and easier than ever before, but what happens if your business grows or shrinks?
In most cases scaling a VoIP service up won't be an issue, and the provider you're working with will be more than happy to sell you another license for the platform. But what happens if you need to reduce the number of subscriptions you have? Make sure you speak to the VoIP provider about this; the last thing you want is to be tied into a contract for a person no longer in the business.
How secure is the VoIP service?
Technology can be prone to security threats, so understand what security measures are in place to protect your VoIP calls. Can you imagine what might happen if you were, for instance, using call recording and someone got their hands on all of your recorded calls? It doesn't bear thinking about, so make sure you check with your VoIP service provider whether they support secure communications and what measures they have.
Customer support and reviews
As you use the hosted VoIP service, there will likely be certain things you need assistance with, so check with your provider what level of customer support they provide. The best VoIP providers will offer telephone-based support, and we suggest avoiding those that only offer live chat.
Choice of phone numbers
The great thing with business VoIP phones is that you can have a phone number anywhere in the UK. This is great if you're running a market campaign in one city but located somewhere else; all of the calls will still come through to your business phone, but you appear to be local from the customer's perspective.
Number porting
Phone number porting is the process of moving your existing phone number over to the new service. Check with your account manager or customer service that this is available before taking the service out to ensure you can keep your number.
Based close to Bournemouth, T2K was founded over 28 years ago as a specialist business telephony provider. Today, we support hundreds of businesses and thousands of users across the UK with both hosted and onsite phone systems. Our customers range from small businesses to large multi-site organisations with complex networking requirements. Being at the forefront of the development of VoIP systems, we're perfectly placed to provide you with expert advice based on years of experience. We regularly review all of the UK VoIP providers so that we can make up to the minute recommendations to our customers.
UK Based Customer Service
The strength of our business comes from our customer service; we provide stability, reliability and continuity via our 100% UK based support. Most of our staff have been with us for ten years or more, which means our customers get the same excellent service from our dedicated team, time after time.
We ensure that your business receives the very best customer service available with dedicated account management.
When comparing business VoIP providers, it's essential to find one that's got a track record of reliability. Ultimately the provider you choose will be your telephony partner for the foreseeable future, so you must take your time when you're speaking to the various VoIP providers.