VoIP vs Traditional Landline: Which Is Best for UK Businesses?

VoIP vs landline: what is the actual difference?

A landline carries your call over the copper Public Switched Telephone Network (PSTN). VoIP carries the same call as data over your internet connection. That single change is what enables lower line costs, mobile and desktop apps, and multi-site working — and it is why our business VoIP team treats VoIP as the default for any UK SME, not a nice-to-have.

The practical differences show up in the bill and in what each system can do:

The honest summary: a landline does one thing — connect a fixed handset to a phone number. VoIP does that plus everything a modern, hybrid workforce expects, usually for less money per user.

How much does VoIP actually save compared to a landline?

Most businesses save 40–60% on telephony costs after switching to VoIP (typical UK 2026 range), because VoIP is priced per user with UK calls bundled, while landlines charge per physical line plus per-minute call rates. The bigger the team and the more sites you run, the wider the gap.

Worked example for a typical 20-user office:

• VoIP: from £5.95 per user per month, calls included, call recording and apps bundled.
• Landline: £15–£30 per line per month, plus per-minute charges, plus paid add-ons for recording and IVR.

On top of the line saving, VoIP removes the cost of physically cabling new desks or sites — you add a user in software, not with an engineer visit. Compare a hosted setup in detail on our hosted phone system page before you size your plan.

Is VoIP call quality as good as a landline?

On a stable connection, VoIP quality matches or beats a landline, because VoIP supports HD voice codecs that the analogue PSTN never could. Quality only suffers when the underlying internet connection is congested or unreliable — which is a connectivity problem, not a VoIP problem.

UK fixed broadband averaged a 69.4 Mbps download speed (Ofcom, Connected Nations 2024), which comfortably carries dozens of simultaneous VoIP calls — a single HD call uses under 0.1 Mbps. If your office runs a shaky line or you cannot tolerate a single dropped call, put VoIP over a dedicated internet leased line so voice gets guaranteed, uncontended bandwidth.

What protects quality in practice:

• A business-grade connection with headroom, not a consumer line shared with everything else.
• QoS rules that prioritise voice traffic over downloads and backups.
• A provider who actually configures the network, not just ships you handsets.

Why are UK landlines being switched off in 2027?

The PSTN is being retired nationally, so every business still on analogue or ISDN lines must move to an IP-based phone system. Openreach is closing the old network, with the industry switch-off targeted for 31 January 2027; after that, traditional landlines simply stop working.

An estimated 2.4 million UK businesses are still on PSTN or ISDN lines (market estimate as of 2026) and will need to migrate. Ofcom's guidance on the future of landline calls confirms the move from analogue to digital voice is happening across the whole country, not just for early adopters. The risk of waiting is not technical — it is commercial: number-porting queues, engineer availability and last-minute pricing all get worse as the deadline nears. Our PSTN switch-off guide breaks down the timeline and what to do first.

Which businesses should still keep a landline?

Very few. A landline only makes sense as a temporary fallback where a site has genuinely no reliable broadband, or for specific legacy equipment — lift lines, alarm panels, some PDQ card machines — that has not yet been certified for IP. Even then, these are being re-engineered for digital, not preserved.

To be balanced: if your broadband is poor and cannot be upgraded quickly, a rushed VoIP move can hurt call quality. The right answer there is to fix the connection first — or run a leased line — rather than stay on a network that is being switched off regardless. For anyone with a sound connection, there is no business case left for analogue.

How does AMVIA migrate you from landline to VoIP?

We port your existing numbers, supply handsets or softphones, configure call routing, and cut over without downtime on your live numbers. One provider owns the whole switchover, so there is no finger-pointing between your line provider and your phone supplier when something needs fixing.

Where AMVIA fits a UK SME:

• Number porting of every existing geographic and non-geographic number, with no loss of identity.
• Multi-site rollouts run as one system — see multi-site VoIP for branch and home-worker setups.
• Microsoft-native calling if you live in Teams — we set up Microsoft Teams Direct Routing so Teams becomes your phone system.
• Security-first by default: VoIP is an internet service and needs hardening, which is why we treat VoIP security as part of the build, not an afterthought.

One provider. Security-first. Microsoft-certified. That is how we keep a migration boring — which, when it is your phone system, is exactly what you want.