Microsoft Teams Phone vs Zoom Phone: Which Is Best for UK SMEs?

This is a genuine comparison, not a sales pitch. Both platforms are mature, both carry UK numbers, and both are valid replacements for the analogue lines being withdrawn. The decision turns on which collaboration suite your staff already live in and how you want calling, security, and admin consolidated. If you are weighing up business VoIP options for the first time, start with the question of where your team already works.

What's the real difference between Teams Phone and Zoom Phone?

Teams Phone and Zoom Phone both turn an internet connection into a full business phone system. The difference is the suite each is built around: Teams Phone embeds calling into Microsoft 365, while Zoom Phone bolts onto the Zoom meetings platform. For a Microsoft-centric business, that integration decides which one is simpler to run.

Teams Phone lives inside the same desktop and mobile app your staff use for chat, meetings, and file sharing. Zoom Phone is strong, but it assumes Zoom is your collaboration hub — if it is not, you carry two apps and two admin consoles. The cleanest route into Teams calling for most SMEs is Microsoft Teams Direct Routing, which connects UK PSTN calling to Teams without Microsoft's own Calling Plans.

Microsoft documents the Direct Routing architecture and supported session border controllers in its official guidance (learn.microsoft.com), which is worth reviewing before any migration.

How do Teams Phone and Zoom Phone compare on cost?

Cost depends on what you already pay for. If you hold Microsoft 365 Business licences, Teams Phone adds calling on top of software you own; Zoom Phone adds a new line item on a platform you may not. The per-user calling fee matters less than whether you are paying twice for overlapping tools.

Microsoft 365 Business licences run from £4.60 per user per month (Business Basic) to £16.90 (Business Premium), ex VAT on an annual plan, per Microsoft's UK pricing (microsoft.com/en-gb). Calling is then layered on. Through a provider like AMVIA, Teams Direct Routing typically costs from £5.95 per user per month, and your team already has the Teams desktop and mobile app. Zoom Phone requires a separate licence at £10 to £15 per user per month, plus a separate application to deploy and secure.

• Already on Microsoft 365? Teams Phone avoids buying into a second platform.
• Already standardised on Zoom? Zoom Phone keeps everything in one console.
• Mixed estate? Price both against the cost of running two apps, not just per-user fees.

For a fuller breakdown of internet-calling economics, see our guide on VoIP vs landline costs.

Which has better call quality for UK businesses?

Neither platform is meaningfully clearer than the other on a healthy connection. Call quality on both Teams Phone and Zoom Phone is governed far more by your underlying internet — latency, jitter, and contention — than by the vendor's codec. Get the connectivity right and both deliver crisp, reliable voice.

Teams Phone routes over Microsoft's global network; Zoom runs its own backbone. Both perform reliably. For UK SMEs the practical variable is the access circuit: the UK broadband average download speed is 69.4 Mbps (Ofcom Connected Nations 2024), which comfortably supports either platform for typical office headcounts. Ofcom's Connected Nations programme tracks UK fixed-line performance in detail (ofcom.org.uk). Where voice is business-critical, a dedicated circuit removes contention entirely — and tightening call security matters as much as quality, which is why we treat VoIP security as part of the build, not an afterthought.

Which platform is better for the PSTN switch-off?

Both platforms are valid replacements for traditional analogue lines, so either keeps you compliant. The deciding factor is not the switch-off itself but which migration causes least disruption — and for Microsoft 365 businesses, moving calling into Teams is the shorter path.

The UK PSTN switch-off is scheduled for completion by 31 January 2027 (Openreach), after which ISDN and analogue lines are withdrawn. Ofcom oversees the migration of the public phone network to IP (ofcom.org.uk). Teams Phone via Direct Routing offers flexible UK number management and call routing while keeping everything inside your existing Microsoft 365 tenant — no new platform to adopt under deadline pressure. Plan the move early using our PSTN switch-off guidance rather than waiting for your lines to be cut.

When should you choose each option?

Choose on where your people already work, not on a feature checklist. The two platforms are close on capability; the real differentiators are app consolidation, admin overhead, and security model. Pick the one that removes a tool rather than adding one.

Choose Microsoft Teams Phone when: - Your business already runs on Microsoft 365 and Teams is the daily app. - You want one app, one admin centre, and one security model (Entra ID + Defender). - You need UK number flexibility via Direct Routing without Microsoft Calling Plans. - You want calling, chat, and meetings consolidated under a single provider.

Choose Zoom Phone when: - Zoom is already your primary meetings and collaboration platform. - Staff have deep Zoom habits you do not want to disrupt. - Your telephony requirements are simple and platform consolidation is not a goal. - You are not committed to the Microsoft 365 ecosystem.

The momentum is with Teams, reflecting how many businesses are consolidating calling into Microsoft 365. If you want help configuring it, Microsoft Teams Calling is the service to scope.

What does AMVIA recommend?

If your business uses Microsoft 365, we recommend Teams Phone via Direct Routing. It gives full PSTN calling inside the Teams app your team already uses, without buying a second collaboration platform or running parallel admin. One provider, security-first, Microsoft-certified.

AMVIA provides Teams Direct Routing from £5.95 per user per month — competitive against Zoom Phone for M365-centric businesses, and delivered with the calling layer, number porting, and security configured together. If you are Zoom-first, we will still build and support Zoom Phone properly; we just will not pretend it is the cheaper or simpler option when you already own Microsoft 365. For tighter integration, see how we connect VoIP with Microsoft 365.