8 Best Business VoIP Providers and Cloud Phone Systems in 2026

The best business VoIP providers in 2026 are Retell AI, Nextiva, RingCentral, Dialpad, Zoom Phone, 8x8, Ooma Office and GoTo Connect. We compared these VoIP phone service providers on price per user per month, number porting, CRM integration, AI features, SIP and carrier options, and support, using each provider's own pricing pages and docs as of October 2026.

A business VoIP provider is a company that delivers your phone numbers, dial tone and call routing over the internet instead of copper phone lines.

Running a team under 50 people? See our guide to VoIP phone systems for small business.

If the real problem is missed calls rather than the phone system itself, Retell AI, ranked first, is an AI agent that answers calls on top of any of these providers.

Best business VoIP providers at a glance

• Retell AI: Best AI layer for any cloud phone system, answering calls on top of your VoIP provider over SIP
• Nextiva: Best all-around cloud phone system for growing teams
• RingCentral: Best for teams that need deep CRM integration
• Dialpad: Best for sales and support teams that want AI transcription on every call
• Zoom Phone: Best for remote teams already working in Zoom
• 8x8: Best for international calling
• Ooma Office: Best VoIP for small business under 20 seats
• GoTo Connect: Best for multi-location businesses

How do these VoIP providers compare on price, porting and CRM?

Data from each provider's pricing page and docs, checked October 2026.

How does each VoIP provider work with AI voice agents?

An AI voice agent connects to a business VoIP provider in one of two ways: call forwarding to the agent's number, or a SIP trunk pointed at the agent.

Most providers below now sell their own AI receptionist. Retell AI works with all of them, and its custom telephony docs cover both elastic SIP trunking and dialing to a SIP URI.

Sources, checked October 2026: Nextiva pricing, RingCentral pricing, Dialpad pricing, Zoom Phone pricing, 8x8 features, 8x8 SIP trunk FAQ, Ooma Office plans, GoTo Connect pricing.

What is a cloud phone system?

A cloud phone system is a business phone service that runs over the internet from the provider's data centers, so there is no PBX hardware in your office and staff can take calls on a desk phone, laptop or mobile app. Cloud VoIP and business VoIP are other names for the same thing.

Every provider in this list covers the basics: unlimited domestic calling, an auto-attendant, call routing, voicemail transcription and mobile apps. The differences that matter are price per user per month, how easy it is to port your existing numbers, which CRMs it connects to, and how well it works for remote teams spread across locations.

Most providers in this list now sell their own AI receptionist add-on. Retell AI ranks first because it adds a full AI voice agent on top of any of them, over SIP or call forwarding, without changing your phone system.

Business VoIP provider reviews

1. Retell AI: Best AI Layer for Any Cloud Phone System

What does it do? Retell AI is an AI voice agent platform that answers calls on top of the phone system you already have. It is not a dial-tone replacement: your numbers stay with your VoIP provider or carrier, and calls reach the agent over SIP.

Who is it for? Teams that already have a VoIP provider but lose calls to voicemail during lunch, after hours or at peak times.

Retell connects to the carrier you already use through elastic SIP trunking, and you can import existing numbers from Twilio, Telnyx, Vonage or any provider that supports SIP trunks (docs). The agent answers questions from your knowledge base, books appointments, and transfers to a person with a private summary of the call first. After every call it logs a transcript, summary and the fields you choose, and can write them to HubSpot or Salesforce. One senior-care provider raised its scheduling NPS by 38% after moving booking calls to Retell.

Pros

• Answers calls 24/7 on top of any SIP carrier, so you keep your numbers and phone system
• Warm transfer with a private call summary for the person who picks up
• Transcript, summary and custom fields logged after every call, with HubSpot and Salesforce sync
• SOC 2 Type I and Type II, HIPAA with a self-service BAA, GDPR

Cons

• Not a phone system on its own, so you need a VoIP provider or SIP carrier behind it

Pricing $0.07 to $0.31 per minute, pay as you go, with no per-user or platform fee, $10 in free credits and 20 free concurrent calls (extra concurrency is $8 per month each). Retell does not charge for telephony when you use your own SIP trunk. Enterprise pricing available. See Retell pricing.

2. Nextiva: Best All-Around UCaaS for Growing Teams

What does it do? Nextiva is a unified cloud phone system that bundles voice, video meetings, team chat, and SMS, with a recent push into customer experience and AI features.

Who is it for? Mid-market teams that want one vendor for calling, meetings, and messaging with 24/7 support that actually picks up.

Where Nextiva strains is the jump from "Core" phone service at $15/user to the full customer-experience platform, which is $75/user/month for its Scale tier. That gap is where buyers get surprised at renewal. Integrations are also narrower than RingCentral at roughly 20 native CRM connectors.

Pros

• Strong support: Nextiva's customer support rated 9.0 out of 10 on G2 versus RingCentral's 7.9 Getnextphone
• 99.999% uptime commitment
• Unified app works cleanly for calling, chat, and video together
• Competitive starting price at $15/user/month (annual)

Cons

• Limited native integrations (~20) compared to competitors with 300+
• Pricing for the CX tier rises to $75/user/month
• Annual contracts with auto-renewal; month-to-month costs about 50% more ($23 vs $15 on Core)

Pricing NEXT Core $15/user/month billed annually ($23 billed monthly), NEXT Engage $25 ($50 monthly), NEXT Scale $75. The XBert AI Employee, Nextiva's AI voice agent, starts at $99 per month (Nextiva pricing).

3. RingCentral: Best for Enterprise Teams with Deep CRM Integration Needs

What does it do? RingCentral offers a full UCaaS platform with voice, video, and messaging, backed by the largest integration ecosystem in the category.

Who is it for? Larger companies running Salesforce, HubSpot, Zendesk, or Microsoft Teams who need certified integrations and can absorb a higher per-seat cost.

The tradeoff is cost and complexity. Core at $20/user excludes CRM integrations, which are gated to Advanced at $25. Most small teams end up paying the middle tier and still wanting more. G2 reviews from early 2026 repeatedly flag long support queues and number-porting delays described as "multi-week sagas."

Pros

• Largest integration ecosystem, with over 330 integrations covering CRMs, project management, and helpdesk systems Premierbusinessteam
• Video meetings support up to 300 participants per call, strong for all-hands
• Mature enterprise compliance (SOC 2, HIPAA, HITRUST)
• Reliable call quality at scale

Cons

• Starting price $20/user billed annually ($30 monthly), the most expensive published entry tier in this comparison
• Admin UI is complex; onboarding takes longer than modern competitors
• SMS cap of 25 messages per user on the Core plan
• Support response times and porting friction are documented in recent reviews

Pricing RingEX Core $20, Advanced $25 and Ultra $35 per user per month billed annually ($30, $35 and $45 billed monthly). The AI Receptionist (AIR) add-on starts at $39, and AI Customer Engagement bundles are quote-based (RingCentral pricing).

4. Dialpad: Best for Sales and Support Teams That Want AI on Every Call

What does it do? Dialpad is a UCaaS platform with AI transcription, sentiment analysis, and live coaching built into every call tier.

Who is it for? Sales and support teams that would otherwise buy Gong or Chorus separately and want coaching baked into the phone system.

Dialpad shines for teams that want coaching without buying a separate platform. The weakness is integration breadth: Dialpad primarily integrates with Google Workspace and Microsoft 365 Premierbusinessteam, which hurts if your stack lives in Salesforce or Zendesk. Dialpad now also sells AI Agents for voice and digital channels, billed per conversation (Dialpad pricing).

Pros

• AI transcription and summaries included in base plan, not as an add-on
• Clean modern UI, faster to learn than RingCentral or 8x8
• $15/user/month Standard tier billed annually ($27 monthly), $25 for Pro

Cons

• CRM integrations start on the $25 Pro plan, not Standard
• Integration ecosystem narrower than RingCentral's
• Upper-tier AI Sales Center and Contact Center plans scale quickly in price
• SMS registration process can be slow

Pricing Standard $15/user/month and Pro $25/user/month billed annually (Standard is $27 billed monthly), Enterprise custom pricing. Dialpad Sell starts at $39 and Dialpad Support at $89 per user per month, and AI Agents bill per conversation (Dialpad pricing).

5. Zoom Phone: Best for Teams Already Living Inside Zoom

What does it do? Zoom Phone extends the Zoom app into business telephony with calling, SMS, and routing inside the same interface as Zoom Meetings.

Who is it for? Teams already running Zoom for video who want one app for calls and meetings without adding a separate vendor.

Zoom Phone is a strong option if Zoom is already a daily tool. It's weaker as a standalone phone system: AI features are thinner than Dialpad's, the contact-center depth is limited, and the per-minute metered plan can become expensive for outbound-heavy teams. Pricing also has multiple tiers that confuse buyers comparing headline prices to reality.

Pros

• Unlimited US and Canada calling from $16/user/month (billed annually)
• Native escalation from voice call to Zoom meeting in one click
• Familiar UI for any team already on Zoom, with near-zero training
• Bring your own carrier (BYOC) support listed on every phone plan, so you can keep an existing SIP carrier

Cons

• AI layer is thinner than Dialpad or Retell AI
• Metered plan can be expensive for high-volume outbound
• Contact center features available only as a separate add-on
• Support quality varies depending on ticket type

Pricing US & CA Unlimited $16/user/month billed annually ($18 monthly). Pro Plus bundle $20.50 and Business Plus bundle $24.50 per user per month billed annually ($24 and $29 billed monthly) (Zoom Phone pricing).

6. 8x8: Best for International Calling and Large Video Conferencing

What does it do? 8x8 is a UCaaS platform strong on global reach, with unlimited international calling bundled into higher tiers and 500-participant video meetings.

Who is it for? Businesses with distributed teams across multiple countries or those running large webinars alongside day-to-day calls.

Where 8x8 wins is global and big meetings: 500-participant video is the highest in this comparison. Where it loses is pricing transparency and mobile experience. Several users in recent reviews flagged the iOS and Android apps as less polished than Ooma's or Nextiva's.

Pros

• Unlimited calling to 14 countries on X2 and up to 48 countries on higher tiers (8x8 calling zones)
• 500-participant video conferencing, the highest in this list
• License-free Microsoft Teams integration available
• Contact center options scale into enterprise territory

Cons

• No public pricing: every buyer negotiates
• Interface feels dated compared to modern competitors
• Mobile apps less intuitive than Nextiva or Ooma
• Support response times reported as inconsistent

Pricing Custom pricing for X Series plans. 8x8 says annual plans save up to 25% (8x8 plans). Contact 8x8 for a quote.

7. Ooma Office: Best Budget Pick for Small Offices Under 20 Seats

What does it do? Ooma Office is a VoIP service aimed at small businesses, with 50+ features included on every plan and month-to-month billing.

Who is it for? Retail shops, restaurants, small clinics, and service businesses with 2 to 20 employees that want a reliable phone system on a tight budget.

The ceiling is real. AI transcription and insights are only on Pro Plus, integrations stop at Salesforce and Microsoft Dynamics plus a few others, and international calling is metered. Video is limited to the Pro and Pro Plus tiers with smaller participant caps. For a 2-person retail store, it's hard to beat. For a 50-person sales team, it's a bad fit.

Pros

• Lowest no-contract entry price at $19.95/user/month with 50+ features included
• Month-to-month billing, no early termination fee
• 24/7 customer support on every plan
• Pre-provisioned hardware makes setup fast for non-technical users

Cons

• AI transcription and insights only on the top Pro Plus tier
• Limited integrations (~10 total)
• CRM integration, call queues and AI transcription require the $29.95 Pro Plus plan
• Scales poorly past 20 seats

Pricing Essentials $19.95/user/month, Pro $24.95, Pro Plus $29.95, all no-contract. An AI Receptionist add-on is available, and the custom-priced Enterprise plan adds SIP trunking. Hardware sold separately, with IP phones from $59.99 (Ooma Office pricing chart).

8. GoTo Connect: Best for Multi-Location Admins Managing Several Sites

What does it do? GoTo Connect is a cloud phone system with particularly strong multi-location admin tools, a visual dial plan editor, and AI receptionist add-ons.

Who is it for? Businesses running 3+ physical locations that need centralized call-flow management and straightforward device provisioning.

The downside is cost and integration depth. The third-party integration library is narrower than RingCentral's. GoTo also acquired Grasshopper, which creates some portfolio overlap and occasional support confusion for customers straddling both products.

Pros

• Best-in-class multi-location admin tools with visual dial plan editor
• A Phone System + AI Receptionist plan includes 100 AI Receptionist credits
• SOC 2 Type II and ISO 27001 certifications
• Straightforward device provisioning across sites

Cons

• No public pricing, so every buyer needs a sales quote
• Fewer integrations than RingCentral
• Reporting less customizable than Dialpad's
• Digital fax feature reported as clunky in user reviews

Pricing Custom pricing. GoTo sells Phone System, Phone System + AI Receptionist, CX, CX Complete and Contact Center plans through sales (GoTo Connect pricing).

How we compared these providers

Total Cost of Ownership, Not Sticker Price

I looked at real monthly cost, including taxes, porting fees, and required add-ons. Sticker prices on landing pages rarely match invoice reality.

AI Call Handling Depth

I looked at whether each provider actually answers calls conversationally or just transcribes voicemails after the fact.

SIP Flexibility and Carrier Choice

I weighted heavily whether a provider locks you into its own telephony or lets you bring a SIP trunk. Bring-your-own-carrier is the difference between a 30-minute migration and a 30-day cutover when you need to switch.

Integration Ecosystem Depth

CRM, helpdesk, and calendar integrations matter more than raw count. I checked specifically for Salesforce, HubSpot, Zendesk, Microsoft 365, and Google Workspace native connectors, since those cover most buyer stacks.

What do businesses use VoIP for in 2026?

After-hours inbound answering. Pairing a VoIP provider with an AI answering service closes the coverage gap without paying for a night-shift receptionist.

Appointment booking during peak hours. Dental, medical, and service businesses lose bookings when three front-desk lines are all busy. An AI appointment setter handles overflow calls, checks a shared calendar in real time, and books slots without putting callers on hold.

Inbound lead qualification for sales teams. Routing inbound calls through lead qualification before they reach a rep ensures only qualified prospects hit the calendar. Every call is logged into the CRM.

Multi-location front-desk coverage. Franchises and clinics with 3+ sites struggle with inconsistent call handling across locations. AI-powered receptionists run the same script at every branch while GoTo Connect or Nextiva handles the dial tone.

High-volume outbound campaigns. Collections, reminders, and survey calls scale poorly on human-seat pricing.

International support coverage. Teams supporting customers across regions benefit from providers like 8x8 for international VoIP minutes and AI platforms for 24/7 multi-language coverage.

What can go wrong with business VoIP?

Network quality is the ceiling. VoIP performance depends on internet stability. Jitter and packet loss turn into dropped calls and robotic audio, and AI layers amplify the problem because context gets lost when a sentence stutters. Upgrading to a dedicated business internet circuit is often step one.

Hidden taxes and regulatory fees. Published pricing rarely includes E911 fees, universal service fund surcharges, and state-level telecom taxes. Ask each provider for a sample invoice before you sign.

Number porting timelines: Porting a business number from a legacy carrier is not instant. Plan the migration around low-volume periods and keep the old line active as backup.

Compliance complexity in regulated industries: Healthcare and financial services require specific BAA contracts and call-recording consent flows. See the HHS HIPAA telehealth guidance for current rules on recorded calls and PHI.

Annual contracts and auto-renewal traps: Most providers default to annual billing with auto-renewal. Month-to-month billing usually costs more per user than annual. Read cancellation terms carefully before signing.

Business VoIP FAQ

What is the best VoIP for small business?

For a small business under 20 seats, the best VoIP provider is usually the one with no contract and every feature on the base plan; in this list that is Ooma Office. If you want AI transcription on every call, Dialpad's entry plan includes it. When comparing cloud phone systems for small business, check three things before price: whether you can keep your number, whether the plan is month to month, and whether the auto-attendant is included or an add-on.

Which VoIP providers work best for remote teams?

Remote teams need a cloud phone system that works the same on a laptop, a mobile app and a desk phone, with one number per person that follows them anywhere. Zoom Phone suits teams already meeting in Zoom, and 8x8 suits teams spread across countries. For any provider, test call quality on home internet, since VoIP quality depends on the connection.

Which business VoIP provider offers the best price-to-feature ratio for small teams?

For teams under 20 seats with basic calling needs, Ooma Office at $19.95/user/month with no contract delivers the most features per dollar. For teams that need modern AI transcription baked in, Dialpad Standard at $15/user/month is the better pick since AI is included on the base plan instead of a $15 add-on.

How does a business VoIP provider compare to an AI voice agent platform?

A business VoIP provider gives you dial tone, numbers and routing. It moves voice packets. An AI voice agent platform like Retell AI answers calls conversationally and executes tasks like booking or call transfer. Most 2026 stacks use both: a VoIP carrier for the SIP trunk and an AI layer for inbound handling.

Can any business VoIP provider handle 24/7 inbound calls without hiring more staff?

Some can now, through paid AI receptionist add-ons such as RingCentral AIR, Nextiva XBert and GoTo AI Receptionist. Without one, a VoIP provider sends after-hours calls to voicemail. An AI voice agent like Retell AI answers those calls around the clock on top of any provider.

What is the real cost of a business VoIP provider beyond the per-seat price?

Expect E911 fees, federal and state telecom taxes, and SMS registration fees on top of the per-user price. Ask each provider for a sample invoice before you sign.

Which business VoIP provider is best for healthcare practices under HIPAA?

RingCentral and Nextiva both sign HIPAA BAAs for covered services. RingCentral lists RingEX and its AI Receptionist as covered, and Nextiva limits some features on HIPAA accounts. 8x8 and GoTo Connect also support HIPAA workflows. If the use case includes AI-handled patient calls, verify the BAA covers the AI layer specifically. Retell AI offers a self-service HIPAA BAA portal, while some AI add-ons from traditional VoIP vendors require custom contracts.

Does a business VoIP provider lock you into its telephony carrier?

It depends. RingCentral and Nextiva bundle their own carrier on standard plans. Zoom Phone supports bring your own carrier (BYOC), 8x8 sets up SIP trunks through its professional services team, and Ooma includes SIP trunking on its Enterprise plan. Pure AI voice platforms like Retell AI are carrier-agnostic and work over any SIP trunk. That is useful if you want to keep an existing carrier while upgrading the intelligence layer.

How does number porting work when you switch VoIP providers?

Number porting moves your existing business number from your old carrier to the new VoIP provider, so customers keep calling the same number. You submit a port request with a recent bill from the old carrier and a letter of authorization; the new provider handles the transfer with the old carrier. Keep the old service active until the port completes, then test inbound calls before you cancel it.

How do I connect an AI voice agent to my business VoIP provider?

You have two options: forward a number, queue or IVR branch to the AI agent, or point a SIP trunk at it. Retell AI supports elastic SIP trunking and dialing to a SIP URI, and does not charge for telephony on your own trunk.