5 Best Business VoIP Phone Systems | UK Comparison
The five best business VoIP phone systems for UK companies are Gamma Horizon, RingCentral, 3CX, Microsoft Teams Phone, and 8x8. Each suits different business profiles — from SMEs wanting a managed hosted system to Microsoft 365-heavy organisations consolidating communications. Pricing ranges from £8 to £25 per user per month.
Nathan Hill-Haimes
Technical Director
Choosing the Right VoIP System
The UK hosted VoIP market has matured significantly. The platforms available today range from polished, fully managed hosted PBX solutions to developer-friendly open platforms. Selecting the right one depends on your business size, the features you need, your existing technology stack, and your appetite for self-management versus a fully managed service.
The five platforms below represent the strongest options for UK businesses in 2025, evaluated on features, pricing, reliability, support, and fit for common SME scenarios.
1. Gamma Horizon
Gamma Horizon is a carrier-grade hosted VoIP platform popular with UK SMEs and mid-market businesses. It is built on Broadsoft (now Cisco Broadworks) — the same platform used by many UK telecoms operators — and delivers a comprehensive, reliable feature set with strong uptime SLAs.
- Key features: Auto-attendant, hunt groups, call recording, analytics, voicemail to email, mobile app, Microsoft Teams integration
- Pricing: Approximately £12–£18 per user per month
- Best for: Businesses wanting a UK-carrier-backed, fully managed hosted phone system with strong technical support
- Strengths: Excellent UK network infrastructure, strong partner support through resellers like AMVIA, proven uptime record
2. RingCentral
RingCentral is a US-headquartered UCaaS (Unified Communications as a Service) platform with a strong UK presence. It combines VoIP calling with team messaging, video meetings, and a wide library of third-party integrations.
- Key features: VoIP, team messaging, video, extensive CRM integrations (Salesforce, HubSpot, Dynamics), call analytics, contact centre add-on
- Pricing: Approximately £15–£25 per user per month
- Best for: Businesses that want to consolidate calling, messaging, and video in one platform with deep CRM integration
- Strengths: Very wide integration library, strong enterprise feature set, global footprint for multinational businesses
3. 3CX
3CX is a software-based IP PBX that can be deployed in the cloud, on a private server, or on-premise. It offers significant pricing advantages compared to fully managed platforms, particularly for larger user counts, and provides a high degree of configuration flexibility.
- Key features: Full hosted PBX, video conferencing, web client, mobile apps, CRM integrations, call centre features
- Pricing: From approximately £8–£14 per user per month (hosted), or annual licence fee for self-hosted
- Best for: Businesses wanting cost efficiency and configuration control; IT-literate teams comfortable managing the platform
- Strengths: Competitive pricing, strong feature depth, flexible deployment options
4. Microsoft Teams Phone
Microsoft Teams Phone adds PSTN calling capability to Microsoft Teams — enabling Teams to make and receive external calls as a full business phone system. It is most compelling for businesses already running Microsoft 365, as it consolidates calling with existing collaboration tools.
- Key features: VoIP calling from Teams interface, voicemail, call queues, auto-attendant, call recording, integration with all M365 apps
- Pricing: Teams Phone licence £6–£12 per user per month + Calling Plan £5–£9 per user per month
- Best for: Microsoft 365 users who want to use Teams as their phone system without a separate VoIP platform
- Strengths: Deep M365 integration, single interface for all communications, familiar to Teams users
5. 8x8
8x8 is a UCaaS platform with a strong presence in the UK mid-market. It offers a good balance of features, usability, and pricing across its X-series plans, and is particularly well regarded for its contact centre capabilities.
- Key features: VoIP, video, team messaging, analytics, contact centre, AI-powered features
- Pricing: Approximately £12–£20 per user per month
- Best for: Businesses with contact centre or customer service teams that need strong analytics and call management
- Strengths: Strong analytics, contact centre features, competitive enterprise pricing
How to Choose
For most UK SMEs under 50 users wanting a straightforward managed system: Gamma Horizon or 3CX. For Microsoft 365-heavy businesses: Teams Phone. For businesses needing deep CRM integration: RingCentral. For contact centre operations: 8x8 or RingCentral Contact Centre.
AMVIA works with Gamma Horizon, 3CX, and Microsoft Teams Phone and can provide independent advice on the right fit for your business.
Which VoIP System Is Right for You?
AMVIA compares VoIP platforms based on your team size, feature needs, and existing technology — and provides a clear, independent recommendation at no cost.
Frequently Asked Questions
For small UK businesses (fewer than 20 users), Gamma Horizon and 3CX are strong choices — both offer professional features at competitive prices with reliable UK-based infrastructure. Microsoft Teams Phone is ideal for businesses already using Microsoft 365. The right choice depends on your specific requirements and existing technology.
Business VoIP in the UK typically costs £8–£25 per user per month depending on the platform and feature tier. Entry-level plans (Gamma, 3CX) start around £8–£12. Mid-range plans with analytics and integrations cost £12–£18. Enterprise platforms (RingCentral, 8x8) typically start at £15–£20. <strong>Microsoft Teams Phone has surpassed 26 million PSTN users worldwide</strong> as of December 2025 — up from 20 million in April 2024, representing 30% growth in 20 months. <em>(UC Today)</em>
Yes. RingCentral has a UK entity and provides services to UK businesses with local phone numbers, UK-based support, and GDPR-compliant data handling. Pricing for UK customers is comparable to US pricing, typically £15–£25 per user per month depending on plan.
Yes, with a Teams Phone licence and a calling plan or direct routing. Teams Phone adds PSTN calling to Teams — enabling external calls through the Teams interface. It works best for businesses already using Microsoft 365 who want to consolidate communications without a separate VoIP platform. <strong>6 million new Teams Phone PSTN users were added in 8 months</strong> (April 2024 to December 2025), confirming Teams as one of the largest cloud PBX platforms globally. <em>(UC Today)</em>
Gamma Horizon is a fully managed hosted service — the platform is managed entirely by Gamma and its reseller partners. 3CX is a software PBX that requires more configuration and management, but offers more flexibility and lower pricing at scale. Gamma suits businesses wanting a fully managed solution; 3CX suits those with IT capability or a managed IT provider.
All five platforms fully support remote and hybrid working. Users access their extension through a mobile app or desktop softphone from any location with broadband. Calls can be transferred, recorded, and managed exactly as if the user were in the office.
Related Reading
Comparison of the Top UK VoIP Providers | AMVIA 2025
Side-by-side comparison of UK VoIP providers on pricing, features, uptime, and customer support.
How Much Does VoIP Cost? | UK Business Pricing Guide
A clear breakdown of VoIP costs for UK businesses — per-user pricing, hardware, and what to budget for.
Choosing the Best Business VoIP Providers | Buyer's Guide
A step-by-step guide to evaluating VoIP providers for your UK business.