How Do I Choose the Right Phone System for My Business?
We make our living from IT support contracts, not phone contracts, so we're genuinely indifferent to which system you pick. This is a straight answer to a decision every UK business now has to make before the old phone network switches off in January 2027.
The Short Answer
For most UK SMEs the choice now comes down to two sensible options: Microsoft Teams Phone if you're already on Microsoft 365 and mainly need straightforward calling, or a dedicated platform like Wildix if calls are core to how you win and serve customers and you need deep CRM integration and call analytics. Whatever you pick, the deadline is real — the old phone network switches off in January 2027.
Why you have to make this decision now (the 2027 switch-off)
The reason we're writing this now, rather than in a couple of years, is simple: the UK's traditional analogue phone network — PSTN and ISDN — is being permanently switched off by 31 January 2027. This isn't a marketing deadline invented to sell you something; it's an industry-wide migration away from copper lines to internet-based calling.
It also isn't just about desk phones. Alarms, lift emergency lines, door-entry systems and card machines often run on the same copper line, and they'll stop working too. A lot of businesses discover these dependencies only when something goes quiet, so they're worth mapping before you do anything else.
Stop-sell rules are already in force, which means you can no longer buy or modify legacy copper lines — the door to the old world is effectively already shut. Practically, the risk of leaving it late is a scramble for install slots through 2026 as everyone migrates at once. Moving earlier gives you a calmer switch and time to test.
What are your actual options in 2026?
Strip away the marketing and there are three realistic routes for a UK SME. Most businesses land on the first two.
Microsoft Teams Phone
Turns the Teams you already have into a phone system. Best fit if you're already on Microsoft 365 and your calling is fairly standard — you'd rather add calling to a platform you already run than stand up a separate one.
A dedicated UCaaS platform (e.g. Wildix)
A proper business communications platform. Best fit if calls are central to the business and you need CRM integration, contact-centre features and analytics — a purpose-built tool for teams whose day is the phone.
Hosted VoIP / SIP to an existing PBX
For businesses keeping on-site kit that's still SIP-capable, or with specific needs the two options above don't meet. It's less common now, but it's a sensible bridge when there's hardware worth keeping.
If you want the underlying voice, data and connectivity side of this explained in plain terms, our voice, data and hardware page covers how the connectivity fits together.
How much does a business phone system cost? (UK, 2026)
Honest ballpark figures below — all approximate, and vendor pricing moves, so treat these as a starting point and check current pricing before you rely on them.
Teams Phone Standard add-on
~£6–£6.60 per user/month, on top of an Microsoft 365 plan that already includes Teams — and before you add a calling plan or SIP trunk.
Realistic all-in for Teams Phone
Roughly ~£12–£30 per user/month once you include a calling plan and connectivity. The range is wide because it depends heavily on how you make calls.
Wildix / dedicated UCaaS
Typically priced per user/month too, but it varies more with features, contact-centre needs and integration work. Get a quote rather than trust a headline figure — the number on a web page rarely matches what you actually need.
The honest point: the licence is the predictable bit. Connectivity and call volume are what actually move the total, so a per-user headline figure only tells you part of the story. For a fuller breakdown, see our telephony pricing page.
When Teams Phone is the right choice
Let's be genuinely fair to Teams Phone, because for a large share of ordinary SME offices it's the sensible default and there's no need to overthink it. If you're already invested in Microsoft 365, you're paying for the underlying platform anyway — Teams Phone just switches on calling.
It's a good fit when:
- You're already invested in Microsoft 365
- Your calling needs are standard — make and receive calls, voicemail, a simple auto-attendant and call queues
- You value having one platform for chat, meetings and calls
- You want the lowest incremental cost
If that's you, the honest answer is to use Teams Phone and move on. Much of this decision only gets complicated when calls are central to how you make money — which is where the next section comes in. It's also worth making sure you're getting full value from the Microsoft licences you already pay for; our guide on Microsoft 365 management for SMEs covers that, and if you're weighing the wider platform choice, our Microsoft 365 vs Google Workspace comparison is a good companion read.
When we'd recommend Wildix instead
This is our honest preference in the right circumstances, so it's worth being specific about why — because the reason is practical, not commercial.
Wildix is a full communications platform with open, documented APIs, which means it can be integrated deeply with the tools a business already runs on. We've used those APIs to build integrations ourselves with property-sector CRMs — Reapit, Street and Loop — as well as generic CRMs like Salesforce and HubSpot. That's first-hand work, not a spec sheet we're repeating.
Its AI and call-analytics capabilities — via x-bees and the analytics tooling — are genuinely strong: conversation transcription, summaries, sentiment and call analytics that log straight into the CRM. Deep CRM integration and AI/analytics are the two specific areas where we've historically hit limitations with Teams Phone, and that's the real reason behind the recommendation.
It's a good fit when:
- Calls are core to how you win and serve customers — estate agents, sales-led firms, anywhere call handling and follow-up quality directly affect revenue
- You want calls and outcomes tied into your CRM automatically
- You need contact-centre features and real reporting
The honest downsides of Wildix (and of our recommendation)
If we're recommending it, we should be equally straight about where it costs you:
- It's another platform to run alongside Microsoft 365, rather than living inside the Teams you already pay for — that's more moving parts and, often, more cost.
- The integration and analytics strengths only pay off if you'll actually use them. A quiet office that just needs to make and take calls will get most of that value from Teams Phone at lower cost.
- It's a bigger commitment and a more involved setup than switching on a Teams Phone licence.
So, plainly: if you're a light-calling business already happy in Microsoft 365, we'll tell you to use Teams Phone. Recommending Wildix there would be us selling you something you don't need — and that's not how we work.
The questions to ask yourself before you decide
This is a genuine decision checklist, not a funnel. Work through it honestly and the right answer usually becomes obvious.
- 1Are we already paying for Microsoft 365?
- 2How central are phone calls to how we actually make money?
- 3Do we need calls, recordings and outcomes to flow into our CRM automatically?
- 4Do we need contact-centre features — queues, wallboards, proper analytics?
- 5What's still connected to our old copper lines (alarms, lifts, door entry, card machines) that also needs migrating?
- 6Is any existing on-site phone hardware still worth keeping, and is it SIP-capable?
How Genmar would approach it
We'd start with a line audit — what's actually connected, including the non-phone dependencies like alarms and lift lines — then map users to the right platform and the cheapest licensing that fits. Because we support both Teams Phone and Wildix, and make our living from IT support rather than phone contracts, the recommendation isn't decided before we've looked at your situation.
Want an honest steer for your specific setup, before the 2027 install rush?
Talk it through with usFrequently asked questions
The questions UK businesses ask us most often about the phone system decision and the 2027 switch-off.
Do I have to replace my phone system before 2027?
Yes, if it still relies on the old copper network. The UK's traditional analogue phone network (PSTN and ISDN) is being permanently switched off by 31 January 2027, and stop-sell rules are already in force, so you can no longer buy or modify legacy copper lines. Migrate early rather than late — leaving it to 2026 risks a scramble for install slots as everyone moves at once.
Is Microsoft Teams Phone good enough for a small business?
For most standard offices, yes. If you're already on Microsoft 365 and your calling needs are ordinary — make and receive calls, voicemail, a simple auto-attendant and call queues — Teams Phone turns the Teams you already have into a capable phone system at the lowest incremental cost. You only need to look further if calls are genuinely central to how you make money.
Why would I pay for Wildix when I already have Microsoft 365?
Only if calls are core to the business. Wildix earns its place through deep CRM integration, contact-centre features and AI call analytics — transcription, summaries, sentiment and call outcomes logged straight into your CRM. If you're a light-calling office that just needs to make and take calls, that value largely goes unused and Teams Phone will do the job for less.
Can a phone system integrate with my CRM?
Yes. Wildix has open, documented APIs, and we've built integrations ourselves with property-sector CRMs — Reapit, Street and Loop — as well as generic CRMs like Salesforce and HubSpot. That lets calls, recordings and outcomes flow into the CRM automatically rather than being logged by hand.
Will my business keep its existing phone numbers?
Number porting is usually possible, so in most cases you keep your existing numbers when you move to a new system. It's worth confirming this early as part of the migration plan, because porting timescales can affect when you're able to cut over.
What happens to my alarm, lift line or card machine after the switch-off?
These often share the same copper line as your phones and will stop working when it's switched off. Alarms, lift emergency lines, door-entry systems and card machines all need identifying and migrating too. Include them in the line audit up front — they're the dependencies businesses most often forget until it's too late.
Keep reading
Choosing a phone system is one part of choosing the right IT partner. If you're reviewing your provider more broadly, start here.
How to Choose the Right IT Support Provider