Business VoIP and Unified Communications-as-a-Service (UCaaS) platforms replace on-premises PBX hardware with cloud calling, video meetings, team messaging, and contact-center features. The market splits into ecosystem plays (Microsoft Teams Phone, Cisco Webex Calling, Zoom Phone) that extend tools you already own, and independent suites (RingCentral, 8x8, Dialpad) that lead on analytics, integrations, and international coverage. Per-seat list prices range from roughly $10 to $35 per month, but real-world pricing is heavily negotiable at 50+ seats.
| Vendor | Deployment | Pricing model | Typical price range |
|---|---|---|---|
| RingCentral MVP | 100% Cloud (SaaS); mobile, desktop, and browser clients | Per user per month subscription | $20–$35/user/month (Core to Ultra plans); volume discounts available |
| Microsoft Teams Phone | Cloud (Microsoft Azure); PSTN via Calling Plans, Direct Routing, or Operator Connect | Add-on license per user on top of M365 | $8–$15/user/month (Teams Phone Standard or Premium); Calling Plan rates vary |
| Zoom Phone | Cloud (SaaS); PSTN via Zoom carrier, BYOC, or carrier integrations | Per user per month (annual subscription) | $10–$20/user/month; bundled discounts with Zoom One plans |
| 8x8 XCaaS | 100% Cloud (SaaS); global infrastructure across 55 countries | Per user per month; tiered bundles for UC and CCaaS | $28–$57/user/month (UCaaS); CCaaS add-on from $85/agent/month |
| Dialpad | 100% Cloud (SaaS); Google Cloud infrastructure | Per user per month (annual) | $15–$35/user/month (Standard to Enterprise); Ai Contact Center from $80/agent |
| Cisco Webex Calling | Cloud (SaaS); Cisco global data centers; PSTN via Cisco or bring-your-own carrier | Per user per month; partner-delivered pricing | $17–$35/user/month (through partner); volume discounts negotiated |
| Interlink | Cloud VoIP + Managed Services; dedicated account and support team | Per line/seat per month with managed services included | Typically 30–50% below comparable enterprise UCaaS pricing; custom quotes |
RingCentral is the platform that brought the enterprise PBX to the cloud and never looked back. With 400,000+ customers across 46 countries, RingCentral MVP (Message, Video, Phone) replaces your on-premises phone system, your video conferencing tool, and your internal messaging platform with a single cloud app — on any device, in any country. If you're ripping out an aging Avaya or Cisco on-prem PBX, RingCentral is the default replacement that won't require a 6-month implementation.
If your organization runs on Microsoft 365, Teams Phone is the cloud PBX you may already be paying for. Add a Teams Phone license to your existing M365 subscription and your Microsoft Teams becomes a full enterprise phone system — with PSTN calling, call queues, auto-attendants, and voicemail, all inside the Teams app your users already live in. No new app to train, no separate login, no third-party UCaaS bill. For Microsoft shops, it's the lowest total-cost path to ditching the on-prem PBX.
Zoom Phone takes everything organizations love about Zoom's intuitive, reliable video platform and applies it to cloud calling. If your team already lives in Zoom for meetings, Zoom Phone gives them inbound and outbound PSTN calling from the same Zoom client — no new app, no new login, no training barrier. Zoom Phone has grown to 7 million seats faster than any UCaaS platform in history, and its AI-powered call summaries and voicemail transcription are genuinely ahead of competitors.
8x8 is the only major provider that delivers both UCaaS and cloud contact center on the same platform — the same agent identity, the same analytics engine, the same admin portal. Most enterprises run separate vendors for internal UC and customer-facing contact center, creating data silos and disjointed agent experiences. 8x8 XCaaS (Experience Communications as a Service) eliminates that gap, letting agents handle internal collaboration and customer interactions from one desktop without toggling between applications.
Dialpad didn't bolt AI onto an existing phone system — it built AI into the core of its platform from day one. Every call on Dialpad is transcribed in real time, with AI flagging action items, coaching sales reps on competitor mentions, and surfacing answers from your knowledge base when customers ask questions. If you're evaluating UCaaS platforms and AI productivity is a key buying criterion, Dialpad is the benchmark that every other vendor is measured against.
Cisco Webex Calling is the UCaaS platform for organizations that demand enterprise-grade reliability, deep security, and the telephony feature depth that only a company with 40 years of networking DNA can deliver. For organizations migrating off Cisco Unified Communications Manager (CUCM) on-prem, Webex Calling is the natural cloud destination — preserving Cisco endpoint investments and existing admin familiarity while moving call control to Cisco's cloud. If compliance, security, and Cisco ecosystem continuity are your primary buying criteria, Webex Calling is the platform.
Interlink is the VoIP provider that treats your phone system like a managed service — not a software subscription you're handed and left to figure out. Where enterprise UCaaS vendors sell you a portal and a knowledge base, Interlink assigns you a dedicated team, builds the custom call reports your business actually needs, and manages your system on your behalf. For budget-conscious organizations that are tired of paying enterprise prices for features they never use and support that never picks up, Interlink is the alternative worth a conversation.
A single-site business with under 100 users typically cuts over in 2–4 weeks. Multi-site enterprises with contact centers, overhead paging, fax lines, and analog devices should plan 2–4 months, driven mostly by number porting and network readiness assessments.
For a single office with business-grade fiber, usually not. For multi-site deployments on mixed broadband, SD-WAN with voice-aware traffic steering measurably reduces jitter and dropped calls — many of our clients bundle both purchases to negotiate better pricing.
Every profile above links to a full independent review with features, competitor analysis, and a buyer's FAQ. Browse other categories in the vendor directory or get a free, vendor-neutral recommendation from a Compare Select advisor.