Business VoIP Phone System for UK Businesses
AMVIA's managed VoIP phone system replaces your traditional landline with a cloud-based telephony platform — delivering flexible, feature-rich calls over your internet connection. Free UK calls, auto-attendant, call recording, and full mobile integration, from a single monthly price.
A VoIP phone system routes calls over the internet rather than traditional copper lines — enabling flexible working, lower call costs, and integration with Microsoft Teams. UK businesses switching from legacy ISDN or analogue lines typically save 40–60% on monthly telecoms costs. AMVIA manages hosted VoIP for businesses with 5 to 500 users.
What is Business VoIP?
VoIP (Voice over Internet Protocol) is a phone technology that routes calls over your internet connection rather than the traditional telephone network. For businesses, a managed VoIP system replaces an on-premises PBX phone system or ISDN lines with a cloud-hosted platform that delivers the same call quality with greater flexibility and lower cost. The UK's PSTN switch-off — originally scheduled for 2025 and now progressing through 2027 — means that all businesses relying on ISDN or analogue lines will eventually need to migrate to VoIP or a compatible alternative. AMVIA provides managed VoIP phone systems that handle the migration, hardware, and ongoing support as a single monthly service.
What's Included with AMVIA's VoIP Service
A complete cloud phone system — with all the features of an enterprise PBX, without the hardware or complexity.
Unlimited UK Calls
Unlimited calls to UK landlines and mobiles included in your monthly subscription — no per-minute charges, no surprise bills.
Auto-Attendant & Hunt Groups
Professional call routing with customisable auto-attendant menus, hunt groups, and out-of-hours messages — presenting your business professionally to every caller.
Mobile & Desktop Softphone
Take and make business calls on your mobile or laptop using the VoIP softphone app — your business number follows you wherever you work.
Call Recording
Automatic call recording with cloud storage and searchable archives — supporting compliance requirements, training, and dispute resolution.
Call Analytics & Reporting
Real-time and historical call reporting showing call volumes, queue times, agent performance, and missed call rates — accessible from the management portal.
CRM & Teams Integration
Integrate with Microsoft Teams, Salesforce, HubSpot, and other CRM systems — enabling click-to-dial, call logging, and screen-pop from your CRM when calls arrive.
Is Your Business Ready for VoIP?
Key requirements and considerations before migrating to a cloud VoIP phone system.
Sufficient internet bandwidth available
Each concurrent VoIP call requires approximately 100Kbps. A 10-user office with frequent calls needs at least 2–3Mbps dedicated to VoIP traffic — well within the capacity of most business broadband and leased lines.
Network QoS configured
Quality of Service settings on your router and switches prioritise VoIP traffic — preventing call quality degradation when internet usage spikes.
Number porting plan in place
Existing phone numbers can typically be ported to your new VoIP system. AMVIA manages the porting process, coordinating with your current carrier to minimise transition risk.
PSTN migration timeline understood
Openreach is phasing out the analogue telephone network. Businesses on ISDN or analogue lines should plan their migration before their provider initiates it on their behalf.
Hardware requirements assessed
VoIP phones, headsets, and conference units may be needed depending on your team's preferences. AMVIA advises on hardware options and can supply and configure IP phones as part of the service.
Business continuity for VoIP considered
If your internet connection fails, softphone apps on mobile devices can continue routing calls via 4G/5G — preventing total loss of phone service during a connectivity outage.
Why Businesses Switch to VoIP
Traditional ISDN and analogue phone systems are being phased out across the UK. Openreach's copper network — the infrastructure underpinning most traditional landlines — is being decommissioned, and all businesses will eventually need to migrate to IP-based telephony. Many businesses use this mandatory transition as an opportunity to modernise their phone system and reduce costs at the same time.
Over two-thirds (>67%) of UK landlines have already been upgraded to VoIP/digital voice. Full migration is required by January 2027. (Cambridge MC)
Europe's SIP trunking market is growing at a projected CAGR of 9.8% over the forecast period, driven by PSTN retirements and demand for cost-efficient communication solutions. (Zionmarketresearch)
Around 2.4 million UK businesses still operate on PSTN or ISDN lines — the majority being SMEs; approximately 33% of large corporations still rely on analogue for some communications. (Aircall)
The cost argument for VoIP is straightforward. On-premises PBX systems require hardware investment, maintenance contracts, and separate ISDN line rental. A managed VoIP service replaces all of this with a single monthly per-user subscription that includes the platform, unlimited calls, and support. Most businesses see a meaningful reduction in their total telecoms spend after migration.
The flexibility argument is equally compelling. With a VoIP system, adding a new user takes minutes rather than days. Staff can work from any location using the softphone app on their laptop or mobile. Business numbers travel with employees — not with physical handsets. Call routing rules can be changed instantly from the management portal. These capabilities matter more than ever for businesses with hybrid or remote working arrangements.
VoIP and the PSTN Switch-Off
The UK's Public Switched Telephone Network (PSTN) is being decommissioned by Openreach. This affects any business currently on ISDN2, ISDN30, or analogue (POTS) lines — including those provided via BT, Virgin Media Business, or resellers. While the timeline has been extended from the original 2025 date, Openreach is actively progressing the migration, and new ISDN connections are no longer available in much of the UK.
Businesses in affected exchanges are being notified of mandatory migration. Rather than waiting for a forced migration — which may be disruptive and rushed — AMVIA recommends planning a managed transition at a time of your choosing, with proper number porting, hardware assessment, and staff training included.
VoIP Call Quality
VoIP call quality is primarily determined by three factors: internet bandwidth, network configuration, and the quality of the VoIP platform. With adequate bandwidth and proper Quality of Service (QoS) configuration, modern VoIP delivers call quality comparable to — or better than — traditional ISDN.
Common VoIP quality issues arise from misconfigured networks, insufficient bandwidth, or consumer-grade routers that do not prioritise voice traffic. AMVIA's managed VoIP service includes a network assessment prior to deployment, QoS configuration on your router, and ongoing call quality monitoring — addressing the root causes of quality problems before they affect your team.
Microsoft Teams and VoIP Integration
Many businesses use Microsoft Teams for internal communication but rely on a separate phone system for external calls. AMVIA's VoIP service integrates directly with Microsoft Teams via Direct Routing or Microsoft's Operator Connect programme — allowing users to make and receive external calls from within the Teams interface, using their existing business phone number.
This integration simplifies the telephony environment significantly: one client for internal messaging and calls, and one platform for external calls — reducing context-switching and the complexity of maintaining separate systems. Calls appear in the Teams call history, can be forwarded to Teams groups, and support Teams-native features like call transfer and consultation hold.
VoIP for Multi-Site Businesses
Cloud VoIP is particularly well suited to businesses with multiple offices, remote workers, or frequent relocation. Because the phone system is hosted in the cloud rather than on a physical PBX at a single site, there is no "main site" dependency. Staff at any location — or working remotely — connect to the same phone system, share extensions, and can transfer calls seamlessly between sites and individuals.
AMVIA manages multi-site VoIP deployments for businesses across the UK — providing a single management portal for all sites, centralised billing, and unified support regardless of location. Call routing between sites uses the internet connection rather than ISDN tie lines, eliminating per-minute internal call charges.
Frequently Asked Questions — Business VoIP
Existing phone numbers — including geographic numbers (01/02), non-geographic numbers (03/08), and freephone numbers — can typically be ported to your new VoIP service. AMVIA manages the porting process with your existing carrier, coordinating the transfer date to minimise disruption. Porting typically takes 10–20 working days depending on the carrier. You can use temporary numbers during the porting period if needed.
Modern cloud VoIP is highly reliable when deployed correctly. AMVIA's VoIP platform runs on redundant cloud infrastructure with 99.99% uptime. The main variable is your internet connection — if your broadband fails, your VoIP service is affected. AMVIA addresses this by recommending a 4G/5G failover solution for critical sites, and by configuring softphone apps on staff mobiles as a backup. Most businesses find this level of resilience comparable to or better than their previous ISDN setup. <strong>PSTN resilience incidents increased 45% in 2024</strong> — and 2024/25 saw over 2,600 major PSTN resilience incidents — making legacy lines demonstrably less reliable than modern VoIP infrastructure. <em>(UK Government)</em>
Yes — most modern IP desk phones are compatible with cloud VoIP platforms. AMVIA can assess your existing handsets and advise on compatibility. Where new hardware is needed, we supply and configure IP phones from Yealink, Cisco, and Polycom as part of the service. Alternatively, many businesses opt for softphone apps on laptops and headsets — eliminating desk phone hardware costs entirely.
AMVIA's VoIP platform includes flexible time-based routing rules. Outside business hours, calls can be routed to a voicemail box, an out-of-hours message, an on-call mobile, or a third-party answering service — depending on your preference. Rules can be configured per number, per department, and adjusted instantly from the management portal without requiring AMVIA involvement.
Get a VoIP Quote for Your Business
Tell us about your team and current phone setup — AMVIA will provide a fixed monthly price for a complete managed VoIP service, including migration, hardware, and ongoing support.
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