Find your perfect
business phone system

Start by identifying your three most important requirements — typically team size, working style (office, hybrid or remote), and whether you need a specific integration like Microsoft Teams or a CRM. From there, the field narrows quickly. Use the finder above to get a scored recommendation based on your specific answers, then read the full review for your top match before requesting a quote. If you're still unsure, speak with the T2K team — a 15-minute conversation is usually enough to identify the right system.

A hosted phone system lives in the cloud — your provider manages the infrastructure, updates happen automatically, and there is no hardware on your premises to maintain. An on-premise system runs on a server installed in your building, giving you full control over data, configuration and where your calls are processed. Hosted systems like Gamma Horizon and Voiceflex Flow suit most UK SMEs. On-premise systems like Mitel MiVoice Business and 3CX suit organisations with strict data sovereignty requirements or complex call routing needs.

UK business phone system costs vary significantly by system and team size. Entry-level hosted options like Gamma Phoneline+ start from around £5 per line per month. Mid-market hosted systems like Gamma Horizon typically run £12–£18 per user per month. Enterprise UCaaS platforms with AI features sit at £25–£40 per user per month. 3CX is priced per concurrent call rather than per user, which makes it cheaper than per-user alternatives for larger teams — a business with 60 staff rarely has more than 15 simultaneous calls, so they pay for 15 concurrent calls rather than 60 licences. On-premise systems involve higher upfront CapEx but lower ongoing fees. Request a tailored quote for a specific price based on your team size and requirements.

For most small UK businesses — under 25 staff, no specialist compliance requirements, no on-premise preference — Gamma Horizon is the most reliable recommendation. It is the UK's most widely deployed hosted PBX, requires no hardware, has a 99.999% uptime SLA, and is straightforward to manage without IT resource. For micro-businesses and sole traders replacing a traditional landline, Gamma Phoneline+ is the simplest and most cost-effective option. For small businesses that use Microsoft Teams daily, Voiceflex Flow is the strongest choice. Use the finder above to confirm which suits your specific situation.

For remote and hybrid teams, the best VoIP systems are those with native mobile apps, softphone clients, and integration with collaboration tools already in use. Voiceflex Flow is the strongest option for remote-first businesses that use Microsoft Teams — staff make and receive calls natively inside Teams without a separate app or a Teams Phone licence. Gamma Webex suits teams needing a full collaboration platform with AI meetings and messaging alongside carrier-grade telephony. Gamma Horizon's mobile app gives remote workers an identical experience to office-based colleagues with no additional configuration required. See our guide to phone system features for remote and hybrid teams for more detail.

Yes. All six systems support full number porting — your existing geographic number transfers to the new system with no change to your published number or disruption to inbound calls. T2K manages the porting process on your behalf, which typically takes 10–15 working days. There is no need to change your number, update stationery, or notify customers. If you also want to add numbers for other UK locations, use our UK area code finder to search available numbers across all dialling codes.

Not necessarily. Many SIP-compatible IP desk phones can be reprogrammed to work with a new VoIP system. If your existing phones are traditional analogue handsets connected to the PSTN, they will need to be replaced or connected via an ATA adaptor. In most cases, modern cloud phone systems also include softphone apps for computers and mobile devices, which can significantly reduce the need for new hardware. T2K can assess your existing hardware as part of a free pre-migration consultation — no obligation to proceed.

A cloud-hosted system like Gamma Horizon or Phoneline+ can typically be active within 24–48 hours for straightforward new number deployments. Number porting from a previous provider takes 10–15 working days. More complex deployments involving CRM integration, contact centre configuration, or large numbers of users typically take 2–6 weeks from order to go-live. On-premise systems like Mitel MiVoice Business require physical installation and typically take 4–8 weeks depending on site complexity. T2K provides a detailed migration timeline at the quote stage so you know exactly what to expect.