Unified communications (UC) is the umbrella term for platforms that combine voice, video, chat, meetings and file sharing into a single service that a UK SME buys per user per month. In 2026, that means one of four platforms for most UK SMEs: Microsoft Teams Phone, RingCentral, Zoom Phone, or 8×8. The right choice depends on what your team already uses, what your existing licence covers, and how close you are to the 2027 PSTN switch-off.
This guide is a straight buyer’s view for UK SMEs in 2026. It covers what UC replaces, the four platforms in play, cost bands, a decision framework based on your existing stack, and the mistakes that catch businesses out on renewal.
What unified communications replaces
UC replaces three separate things a UK SME used to buy: a desk phone system (PBX), a video conferencing tool, and an instant messaging platform. As a result, UC replaces multiple suppliers, contracts and logins with one user identity and a single interface that brings everything together.
For instance, rather than relying on separate systems, a UC platform gives users one office phone number that can ring on their laptop, mobile app and, if required, a desk phone.
Voicemails arrive in email. Video meetings launch from the same app. Team chat is threaded per conversation. Numbers port with the person when they change desk or move site.
The change compared with 2020 is that the platforms have matured. All four leading UC options now do the core job reliably. Differentiation is on integration, pricing model, and how they fit alongside what you already own.
Why UK SMEs are moving to UC in 2026
Three forces are driving the shift this year.
- The PSTN switch-off deadline. Openreach is retiring analogue PSTN and ISDN by 31 January 2027. Any UK SME still on ISDN lines needs to move to SIP or a cloud UC platform before then. Roughly 500,000 UK business lines were still on legacy services in early 2026.
- Hybrid work made desk phones obsolete for most roles. A cloud UC softphone works from home, office and a customer site with the same extension. On-premise PBXs need a VPN or Session Border Controller to get close to this, at operational cost.
- Cost predictability. UC platforms are per user per month. New starter needs an extension: add a user in the admin console. Leaver: remove them. No hardware refresh cycle. Cash flow becomes predictable OpEx.
The four UC platforms UK SMEs are choosing between in 2026
For the vast majority of UK SMEs, the shortlist is these four. The differences are less about features (all four handle the basics well) and more about fit with what you already run.
| Platform | Best for | Typical UK SME cost (per user/month) |
| Microsoft Teams Phone | Businesses already all-in on Microsoft 365 with Teams as the daily collaboration tool | £6 to £14 as an add-on to M365 |
| RingCentral | Businesses that want a full-stack UCaaS with contact-centre features, without dependency on Microsoft licensing | £15 to £30 |
| Zoom Phone | Businesses whose teams already meet on Zoom and want phone integrated into the same app | £10 to £20 |
| 8×8 | Businesses running UC and a contact centre side-by-side and looking to consolidate | £18 to £35 |
None of these platforms is universally best. The right choice tracks the platform your team already uses for daily collaboration. Force-fitting the wrong platform is where UC projects go sideways.
How to choose: three questions
Most UK SMEs get to the right platform with three questions.
- What does your team currently use for daily collaboration and meetings?
- What licences do you already pay for through Microsoft 365 or another suite?
- Do you need a contact-centre layer (call queues, IVR, analytics) or just business calling?
Team lives in Microsoft 365 and Teams, no heavy contact centre. Teams Phone is usually the shortest path. It layers onto the existing tenant, uses the same identity, and shows up in the app people already have open.
Contact-centre features or non-Microsoft stack. RingCentral outscores the alternatives for most UK mid-market SMEs. However, it sits above your existing tools rather than forcing you to consolidate them. For example, if Zoom is already your default meeting platform and phone is simply an add-on, Zoom Phone can offer the cleanest integration. In addition, it may be more cost-effective when Zoom licences are already in place.
How UC platforms integrate with the rest of your stack
The value of UC compounds when it plugs into the tools your team already uses. All four platforms have integrations libraries, but the depth of integration varies.
- Microsoft 365 and CRM. Teams Phone integrates natively with Dynamics 365 and connects to Salesforce, HubSpot and other mainstream CRMs. Calls log automatically against the contact record.
- Contact-centre bolt-ons. RingCentral and 8×8 both offer contact-centre modules that sit on the same UC platform, sharing user identity and directory. Cleaner than running two separate products.
- Analytics and call reporting. Every platform ships basic call analytics. Advanced reporting (wallboards, agent scorecards, historical trend analysis) is a tier-up feature. Ask before you assume it is included.
- Compliance and call recording. Financial services and regulated sectors need call recording that meets FCA or MiFID II retention rules. All four leading platforms support this but usually on higher tiers.
The practical test: list the five tools your team uses daily and ask each shortlisted UC vendor for a live demo of the integration. Marketing pages promise a lot. A demo shows what works today.
What UC costs in 2026
Sticker price per user is the starting point, not the number that matters. The full monthly picture for a UK SME includes the platform licence, the phone numbers (DDIs), any hardware if you want desk phones, and porting fees when moving from an existing supplier.
- Platform licence: £6 to £35 per user per month depending on platform and tier
- Phone number pool (DDIs): Usually free with the licence, or 50p to £2 per number per month for extras
- Desk phones (optional): £80 to £250 per handset, one-off
- Number porting from existing supplier: Typically £15 to £50 per number, one-off, with a two- to six-week port window
- Contact-centre add-ons (if needed): £20 to £80 per agent per month on top of base UC licence
For a 20-user UK SME with straightforward calling needs, expect £2,000 to £4,000 a year on the platform alone. If Teams Phone works on top of existing M365 licences, that number can be closer to £1,500.
The connectivity that UC depends on
UC quality lives and dies on your internet connection. Voice needs low latency and low jitter, both directions. Video needs bandwidth to spare. If the internet drops, the calls drop, unless the platform has a mobile-network failover on the softphone.
Symmetric upload matters more than raw download speed. A business FTTP with 100 Mbps symmetric usually handles 20 to 30 concurrent UC users comfortably. Larger teams or heavy video call volume tilt toward a leased line.
Common mistakes when picking a UC platform
- Buying the lowest-tier plan and finding feature gaps at go-live. Call queues, call recording, integrations and mobile-app features vary heavily by tier. Compare like for like.
- Ignoring the licence you already own. Businesses on Microsoft 365 E5 already have Teams Phone rights they may not be using. Auditing existing entitlements first can shave a real chunk of the migration cost.
- Underestimating porting time. Two to six weeks per number is normal. Kick off porting early, run the two services in parallel briefly rather than cutting hard.
- Not planning training. UC changes how staff work. A 30-minute walkthrough per team on the first week saves months of low-adoption pain.
- Confusing UC with a contact centre. UC is business calling for whole-organisation use. Contact centre is a specialist layer for customer service teams handling call volume. Different products, different pricing, sometimes bundled.
How to migrate without disruption
The clean migration pattern is a parallel-run window followed by a scheduled cutover. Provision the new UC platform for a small pilot group (five to ten users) first. Port their numbers, run the platform in parallel with the old system for two to three weeks, resolve teething problems. Then roll out to the rest of the business in waves of 10 to 20 users.
The whole migration for a 50-user UK SME typically runs six to twelve weeks from contract to full cutover. Faster than that risks skipped training and staff annoyance. Slower usually means the project has stalled on porting or handset delivery.
Talk to us about your UC setup
If you would like a second pair of eyes on your options from our communications team before you sign the next contract, get in touch and we will walk through your existing licence position, the two or three platforms that make most sense for your business, and where the sensible tradeoffs sit in 2026.