Best Business VoIP Providers UK 2025 | Honest Comparison & Pricing
2025 Comparison Guide

Best Business VoIP Providers in the UK

Compare 7 leading VoIP providers: pricing, uptime SLA & UK support quality

From
£8/user
Average Savings
50–70%
Setup
4–8 weeks
View Comparison Call 0333 733 8050
AMVIA VoIP - UK business phone system with sub-90 second response

What This Page Covers

A transparent comparison of the leading business VoIP providers operating in the UK, evaluating pricing, features, uptime guarantees, UK support quality, and implementation timelines. Includes honest positioning on which providers suit specific industries, team sizes, and business needs.

Pricing Features Uptime SLA UK Support Implementation Industry Fit
01
Key Facts

Key Facts

Essential context on UK VoIP pricing, savings, and implementation realities

Typical Pricing
£8–£15/user
Implementation
4–8 weeks
Uptime Standard
99.9%+
  • Implementation reality: Zero-downtime migrations take 4–8 weeks from discovery to full deployment. Parallel running and number porting are standard.
  • Support quality varies widely: Some providers offer 24/7 UK-based support under 90 seconds; others route you to offshore call centres or ticket queues.
02
Provider Comparison

Main Comparison: Best Business VoIP Providers UK 2025

We evaluated 7 leading VoIP providers based on UK market presence, uptime guarantees, support quality, and pricing transparency.

Provider Best For Starting Price Core Features Uptime SLA UK Support Setup Time
Amvia
Featured
 UK SMEs needing joined-up connectivity + VoIP + Microsoft 365 £8–£12/user/mo Hosted VoIP, Teams Direct Routing, call recording, CRM integration, SIP trunking 99.9% with credits Direct UK experts <90s, named account manager 4–6 weeks
BT Business VoIP
Brand-conscious SMEs, larger enterprises ~£10–£15/user/mo Cloud phone system, call routing, hunt groups, CRM integrations 99.99% 24/7 national operation 4–8 weeks
Gamma Horizon
Microsoft 365 and Teams-heavy ~£10–£20/user/mo Hosted telephony, Teams Phone integration, contact centre 99.999% UK via channel partners 3–6 weeks
Virgin Media Business
Bundling fibre + voice ~£20–£25/user/mo Broadband + telephony bundle, inclusive UK minutes 99.9% Central UK team, variable 4–8 weeks
RingCentral
Large teams (50+) needing UCaaS ~£20+/user/mo Complete UCaaS: voice, video, messaging, contact centre 99.999% 24/7 global enterprise 2–6 weeks
8x8
Contact centres, multi-site ops ~£12+/user/mo UCaaS with contact centre, call recording, analytics 99.999% 24/7 enterprise focus 3–8 weeks
Vonage
Simple bundled VoIP ~£12–£15/user/mo Hosted VoIP, softphone apps, call routing, basic UC 99.99% UK-based, responsive 2–4 weeks

Note: Prices exclude VAT. Contract length, add-ons, and packages vary. Updated December 2025.

03
Selection Criteria

How We Selected These VoIP Providers

We evaluated VoIP providers based on UK market presence, uptime guarantees, support quality, and pricing transparency. Here's exactly what we looked for:

  • UK market presence: Providers actively serving UK SMEs and enterprises.
  • Uptime guarantees: Published SLA commitments and track record reliability.
  • Support quality: Response times, UK-based availability, and customer satisfaction signals.
  • Feature set: Core VoIP capabilities (call recording, CRM integration, Teams integration, call routing).
  • Pricing transparency: Honesty about per-user costs and what's included.
  • Implementation approach: Zero-downtime migration capability, parallel running, and typical deployment timelines.
  • Industry suitability: Proven adoption in legal, finance, retail, and logistics sectors.

We have not ranked these providers numerically because no single "best" provider fits all businesses. Instead, this guide explains strengths, weaknesses, and which industries each serves best. Amvia is included based on our service offering and market presence; we have explicitly noted where other providers may be better suited.

Featured Provider

Amvia: Best for Joined-Up UK Connectivity

UK MSP based in Sheffield serving 2,000+ businesses with leased lines, FTTP, SD-WAN, VoIP, Microsoft 365, and cybersecurity.

AMVIA voice over IP

Direct UK Experts <90s

No voicemail, no offshore call centres, no ticket queues. Named account manager with 24/7 availability.

99.9% SLA with Credits

Uptime guarantee with automatic service credits if breached—transparent financial accountability.

Zero-Downtime Migration

2,000+ implementations with zero failures in 2024. Parallel running and number porting handled completely.

Joined-Up Stack

One vendor for VoIP, broadband, SD-WAN, Microsoft 365—coordinate one vendor instead of five.

"Direct UK expert access is rare and highly valued by SMEs. The difference between providers can mean hours of frustration or instant resolution."

4.6/5 Trustpilot · CityFibre Trusted Partner

Provider-by-Provider Snapshots

Detailed analysis of each VoIP provider's strengths, weaknesses, and ideal use cases

AMVIA
LOGO
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Amvia: Best for Joined-Up UK Connectivity + Communications

£
Starting from
£8–£12/user/mo

Who Amvia is: UK MSP based in Sheffield serving 2,000+ businesses with leased lines, FTTP, SD-WAN, VoIP, Microsoft 365, and cybersecurity managed services.

Core Features

Uptime SLA
99.9% with automatic service credits if breached—transparent financial accountability.
UK Support Quality
Direct UK experts answer in under 90 seconds. No voicemail, no offshore call centres, no ticket queues. Named account manager for every customer. 24/7 availability.
Setup & Migration
4–6 weeks zero-downtime migration. Parallel running allows thorough testing. Handles all number porting paperwork. On-site implementation support included.

Strengths

Direct UK expert access is rare and highly valued.
Zero-downtime migration track record (2,000+ implementations, zero failures in 2024).
Joined-up stack: if you need leased lines, FTTP, SD-WAN, Microsoft 365, or cybersecurity, you coordinate one vendor instead of managing five.
Microsoft-certified partner providing deep Teams expertise.
Transparency on costs, SLA, and support.
4.6/5 Trustpilot rating with CityFibre Trusted Partner certification.

When to Choose Another Provider

  • No global contact centre features (if you need multi-language 24/7 contact centre, RingCentral or 8x8 are better).
  • If your existing BT broadband contract is locked in and you want bundled voice/internet, BT or Virgin Media may offer simplicity.
  • For very large enterprises (500+ users) needing dedicated on-premise infrastructure, on-premise PBX may suit better (though rare in 2025).

Best For Industries

Legal firms (SRA compliance, call recording, UK data residency) Financial services (FCA requirements, secure communications, encryption) Multi-site retail (unified phone system across locations, broadband coordination) Logistics (mobile VoIP for field teams, SD-WAN for branch connectivity)
BT
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BT Business VoIP / BT Cloud Voice: Best for Brand Continuity & Larger Enterprises

£
Starting from
£10–£15/user/mo

Who BT is: UK telecommunications giant with national infrastructure, broadband, and voice services.

Core Features

  • BT Cloud Voice (hosted telephony platform)
  • Call routing and hunt groups
  • Voicemail and call recording
  • CRM integrations
  • Unified communications add-ons
  • Integration with BT broadband services
Uptime SLA
99.99% core network uptime (published).
UK Support Quality
24/7 support via national operation. Large customer base means responsive support infrastructure. Variable response times depending on support tier purchased.
Setup
4–8 weeks depending on team size and existing BT relationships.

Strengths

National brand recognition and trust.
Excellent broadband integration if you're already a BT customer.
Established support infrastructure at scale.
Flexible contract terms and bundling options.
Suitable for enterprises with dedicated procurement teams.

When to Choose Another Provider

  • Support is 24/7 but not always "direct expert in 90 seconds"—typical ticket queues exist.
  • Pricing can be higher than specialist VoIP providers.
  • If you need zero-downtime guaranteed migration, Amvia's track record is more explicit.
  • If you value named account manager relationship, BT's size means more transactional support.

Best For Industries

Larger enterprises (100+ users) Businesses already using BT broadband wanting bundled services Firms prioritizing brand-name stability over innovation
GAMMA
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Gamma Horizon Cloud Phone System: Best for Microsoft Teams & Channel Partners

£
Starting from
£10–£20/user/mo

Who Gamma is: UK telecom company and Horizon cloud phone system provider, primarily sold through approved reseller channel partners.

Core Features

  • Horizon cloud phone system (hosted telephony)
  • Microsoft Teams Phone integration (native calling within Teams)
  • Contact centre options available
  • Advanced call routing and analytics
  • Channel partner administration tools
Uptime SLA
99.999% network uptime (stated).
UK Support Quality
UK-based support available via approved channel partners. Quality varies significantly by partner selected.
Setup
3–6 weeks via channel partners.

Strengths

Strong Microsoft Teams Phone integration.
Extremely high uptime guarantee (99.999%).
Channel partner ecosystem enables customization.
Competitive feature set for Microsoft 365 environments.

When to Choose Another Provider

  • You must work through approved resellers—no direct relationship with Gamma.
  • Support quality depends entirely on which partner you select.
  • If you want direct vendor accountability, this is not ideal.
  • Pricing can vary widely between partners.

Best For Industries

Microsoft 365-heavy organizations valuing Teams Phone Businesses comfortable working through managed resellers
VIRGIN
MEDIA
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Virgin Media Business: Best for Broadband + Voice Bundling

£
Starting from
£20–£25/user/mo

Who Virgin Media Business is: Virgin Media division providing broadband, phone, and bundled business services.

Core Features

  • Hosted telephony + fibre broadband bundle
  • Cloud phone system
  • Inclusive UK minutes
  • Basic voicemail
  • CRM sync capabilities
  • Simplified administration
Uptime SLA
99.9% on core network (typical).
UK Support Quality
Central UK support team, generally responsive, variable experience depending on support tier.
Setup
4–8 weeks, aligned with broadband installation timelines.

Strengths

Simplicity: one vendor for broadband + phone.
Bundled pricing can be competitive if you need both services.
UK infrastructure and national presence.
Straightforward to administer for businesses with simple needs.

When to Choose Another Provider

  • Per-user cost is higher than specialist VoIP providers (though bundled pricing improves ROI).
  • Feature set is simpler than RingCentral or 8x8.
  • If you already have a non-Virgin fibre provider (FTTP, leased line, SD-WAN), bundling benefits disappear.
  • Setup times can extend if broadband installation encounters delays.

Best For Industries

Small to medium businesses (5–30 users) wanting broadband + phone simplicity Offices in areas where Virgin Media fibre coverage is strong
RING
CENTRAL
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RingCentral: Best for Large Teams & Full Unified Communications

£
Starting from
£20+/user/mo

Who RingCentral is: Global cloud communications provider serving enterprises and contact centres worldwide.

Core Features

  • Complete Unified Communications as a Service (UCaaS): voice, video conferencing, instant messaging
  • Contact centre capabilities
  • Deep CRM integrations (Salesforce, Microsoft Dynamics)
  • Advanced analytics and reporting
  • Mobile-first design
  • Global calling and presence management
Uptime SLA
99.999% stated global uptime.
UK Support Quality
24/7 global support, enterprise-orientated, responsive, strong partner ecosystem.
Setup
2–6 weeks (primarily cloud-based deployment, faster than on-premise).

Strengths

Comprehensive UCaaS platform (voice, video, messaging in one solution).
Exceptional for contact centres and large operations.
Advanced analytics and business intelligence.
Strong CRM integrations reduce context-switching.
Global presence for multinational teams.
Highest uptime guarantee (99.999%).

When to Choose Another Provider

  • Higher per-user cost (~£20+) makes it less ideal for cost-conscious SMEs.
  • Complexity of full platform overkill for simple phone system needs.
  • If you want UK-specific support + simple voice-only, Amvia or Gamma are better.
  • Setup and training requirements are higher due to feature richness.

Best For Industries

Large enterprises (100+ users) Contact centres and customer service teams Businesses with complex CRM needs (sales teams using Salesforce heavily) Global operations requiring unified communications across time zones
8X8
LOGO
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8x8: Best for Contact Centres & Multi-Site Analytics

£
Starting from
£12+/user/mo

Who 8x8 is: Global UCaaS and contact centre provider with strong analytics and compliance focus.

Core Features

  • UCaaS: voice, video, messaging
  • Contact centre features (IVR, queuing, recording)
  • Advanced analytics and call recording
  • Global calling
  • CRM integrations
  • Compliance-focused call management
Uptime SLA
99.999% stated uptime.
UK Support Quality
24/7 support, enterprise focus, particularly strong on contact centre support.
Setup
3–8 weeks depending on contact centre configuration.

Strengths

Excellent for contact centres and customer service operations.
Strong call recording and compliance features (valuable for regulated industries).
Advanced analytics help optimize team performance.
Competitive pricing for feature-rich platform.
High uptime guarantee.

When to Choose Another Provider

  • Contact centre complexity may be overkill for simple business phone systems.
  • If you want straightforward UK SME VoIP without contact centre bells, Amvia is simpler.
  • Learning curve on analytics and advanced features.

Best For Industries

Contact centres and customer service operations Financial services (compliance and recording requirements) Multi-site businesses needing unified analytics across locations
VONAGE
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Vonage / Vonage Communications: Best for Simple Bundled Solutions

£
Starting from
£12–£15/user/mo

Who Vonage is: Global communications provider with strong UK presence, offering bundled VoIP and UC solutions.

Core Features

  • Hosted VoIP
  • Mobile and desktop softphone apps
  • Call routing and basic UC
  • Voicemail-to-email
  • Moderate CRM integration options
  • Simple administration
Uptime SLA
99.99% typical uptime.
UK Support Quality
UK-based support with strong reputation, responsive support queue, variable response times.
Setup
2–4 weeks (faster deployment than some competitors).

Strengths

Simple, transparent pricing (fewer confusing tiers).
Good balance of features and ease of use.
UK support reputation is strong.
Straightforward to implement (2–4 weeks typical).
Suitable for SMEs wanting VoIP without complexity.

When to Choose Another Provider

  • Feature set is middle-ground (not as full-featured as RingCentral, not as simple as basic VoIP).
  • If you want zero-downtime guaranteed migration, Amvia's track record is more explicit.
  • If you need contact centre or advanced UC, RingCentral or 8x8 are better.

Best For Industries

Small to medium businesses (10–50 users) Teams wanting straightforward hosted VoIP without complexity

Industry-Specific VoIP Recommendations

Different industries have unique compliance, connectivity, and support requirements.

Best VoIP for Law Firms

SRA Compliance & Call Recording

Legal practices need bulletproof call recording for client documentation, UK data residency for GDPR compliance, and integration with practice management systems.

1. Amvia First Choice

Direct UK support understands SRA requirements, UK data residency, integrated call recording with compliance controls.

2. BT Business VoIP

Established with law firm clients, call recording, reliable uptime.

3. Gamma Horizon

Teams Phone integration for collaboration-heavy firms.

Best VoIP for Financial Services

FCA & Operational Resilience

FCA operational resilience requirements demand robust failover, MiFID II call recording, encrypted communications.

1. Amvia First Choice

FCA-aware implementation, encrypted comms, 4G failover, UK SOC monitoring 24/7.

2. 8x8

Strong compliance features, operational resilience analytics.

3. BT Business VoIP

Established in financial services, compliance track record.

Multi-Site Retail

Unified Phone System

Centralized administration across locations, failover resilience, simple UI for high staff turnover.

→ Amvia

Unified VoIP + SD-WAN across all stores

→ Virgin Media

Broadband + phone bundling

Logistics & Field Teams

Mobile VoIP

Mobile VoIP apps for drivers, 4G/5G failover during travel, fleet management integration.

→ Amvia

Mobile apps + SD-WAN + 4G/5G failover

→ RingCentral

Mobile-first, global presence

How to Choose the Right VoIP Provider

Use this framework to narrow your choices based on team size, budget, and support requirements

1
Team Size & Growth
1–20 users
Simple VoIP
Amvia
Vonage
BT
20–100 users
Mid-market with growth
Amvia
BT
Gamma
Virgin Media
100–500+ users
Enterprise UCaaS
RingCentral
8x8
BT
Amvia
2
Budget & Cost Sensitivity
£8–£15
Cost-conscious SMEs
Amvia
Vonage
Gamma
£10–£25
Mid-market
BT
Virgin Media
£20+
Enterprise
RingCentral
8x8
3
Support Quality Requirements
UK expert <90s, no voicemail
→ Amvia (unique)
24/7 large team support
→ BT, RingCentral, 8x8
Channel partner relationship
→ Gamma

Still unsure which provider fits? Use our recommendations above or scroll up to review the detailed provider snapshots.

View Provider Comparison Table

FAQ: Common Questions

Everything UK SMEs ask about VoIP providers

Who is the best VoIP provider for small businesses in the UK?
There is no single "best" provider—it depends on your industry, infrastructure, and support preferences. For cost-conscious SMEs (5–30 users) wanting direct UK support, Amvia is a strong choice (£8–£12/user, 99.9% SLA, <90s expert access). For brand stability, BT is established. For bundled broadband, Virgin Media.
How much should I expect to pay per user for business VoIP?
Typical hosted VoIP pricing in the UK is £8–£15 per user monthly for SMEs, with all-inclusive call packages. This represents 50–70% savings compared to traditional ISDN (£20–£50/user). Always confirm what's included—some providers charge extra for call recording and CRM integration.
What's the difference between hosted VoIP and on-premise PBX?
Hosted VoIP (cloud phone system) is managed by your provider in the cloud. Benefits: no hardware, automatic updates, lower cost (£8–£15/user), scales easily. On-premise PBX is hardware in your office. For 95% of UK SMEs, hosted VoIP is better due to lower cost and easier management.
Can I keep my existing phone numbers when switching?
Yes. All UK geographic numbers (01, 02), non-geographic (03, 0800, 0845), and mobile numbers port seamlessly. Ofcom regulates the process, typically 5–10 working days with zero service interruption. Your VoIP provider handles all paperwork.
How long does VoIP implementation take?
Complete implementation takes 4–8 weeks. Actual service disruption is measured in hours, not days. Providers like Amvia prioritize zero-downtime migration, allowing parallel running before final cutover.
What happens if my internet fails with VoIP?
Professional VoIP systems include automatic failover. During outages: inbound calls route to designated mobiles, mobile VoIP apps continue via cellular data, emergency calls (999/112) route automatically. Optional 4G/5G backup provides geographic redundancy.
Is VoIP call quality as good as traditional phones?
Yes, modern VoIP typically delivers superior call quality. HD voice codecs (G.722, Opus) provide wider frequency range than traditional telephony, resulting in clearer conversations. 99% of UK businesses report equal or better call quality post-migration.

Implementation Timeline & Next Steps

If You've Decided on a Provider:

1. Request a discovery meeting

30–60 minutes. Discuss your current infrastructure, team size, Microsoft 365 setup, broadband connectivity, and compliance needs.

2. Get a formal proposal

Per-user pricing, setup fees, contract length, and support SLA.

3. Negotiate contract terms

Contract length, early termination, add-on pricing.

4. Plan parallel running

Your old phone system operates alongside new VoIP for 1–2 weeks, allowing staff familiarization and testing before cutover.

5. Schedule cutover

Typically a low-traffic day/time for minimal disruption.

If You Want to Compare Providers:

1. Shortlist 2–3 providers

Based on this guide's recommendations for your industry.

2. Request discovery meetings

Ask the same questions to compare responses.

3. Ask for references

From businesses similar to yours (team size, industry, Microsoft 365 usage).

4. Verify uptime SLA

And service credits for breaches (important, not all providers offer financial accountability).

5. Confirm support availability

Hours, response times, escalation paths.

Summary: Best Business VoIP Providers in the UK (2025)

Provider Best For Starting Price Key Differentiator
Amvia
 UK SMEs, compliance-heavy, joined-up connectivity £8–£12/user Direct UK expert <90s, zero-downtime migration, 99.9% SLA with credits
BT Business
 Brand continuity, larger teams, broadband bundling £10–£15/user National infrastructure, 24/7 support, established enterprise presence
Gamma Horizon
 Microsoft Teams-heavy, channel partner preference £10–£20/user 99.999% uptime, Teams Phone integration, partner ecosystem
Virgin Media Business
 Broadband + phone simplicity £20–£25/user Bundled fibre + voice, one vendor simplicity, cost-effective at scale
RingCentral
 Large enterprises, contact centres, CRM-heavy £20+/user Full UCaaS, 99.999% uptime, Salesforce/Dynamics integration, global
8x8
 Contact centres, compliance, multi-site analytics £12+/user Contact centre features, compliance recording, advanced analytics
Vonage
 Simple VoIP needs, straightforward pricing £12–£15/user Transparent pricing, quick deployment (2–4 weeks), UK support
Next Steps

Final Recommendation

For most UK SMEs (5–100 users), Amvia offers the best balance of direct UK support, transparent pricing, and zero-downtime migration.

Call 0333 733 8050 Request Discovery Call

Remember: Choose based on your industry, team size, and support preferences—not price alone. A £8 provider with poor support becomes expensive when your business can't make calls.

Ready to switch to VoIP?

Contact our team for a free consultation and transparent pricing tailored to your business needs.