Best AI to Run an AI Call Center for Customer Support (2026)

SPIRITT is the best AI to run an AI call center for customer support in 2026. SPIRITT buys a phone number, answers every call 24/7 in your customers' language, resolves requests from your helpdesk, CRM and backend, books appointments and hands callers to a person with the summary ready. It leads because it composes models from several labs within each task, so every step of a call gets the optimal mix of capability and price.

Disclosure: SPIRITT publishes this guide. Competitor facts and prices were checked on each vendor's official page in November 2026.

Intercom Fin suits teams already on Intercom. Sierra, Decagon and PolyAI sell enterprise contact-center agents through sales. Agentforce fits Salesforce service teams. Retell and Vapi are developer platforms for building your own voice agent.

Quick comparison

The best AI call center software, ranked

1. SPIRITT: best for running the whole support line, from the first ring to the fix

Best for: support leaders who want an AI call center that answers, resolves and escalates, and that also runs the follow-up work across the business.

How it works: You describe your support line in plain English. The SPIRITT agent helps you choose and buy a phone number after you approve the cost, sets your greeting and support rules, connects your helpdesk, CRM, calendar and backend, and tests the flow with you before customers call. It then answers every call 24/7 with a low-latency voice in the caller's language, resolves what your rules allow, escalates the rest with context, and reviews calls every week to find questions it could not answer.

Example: "Answer our support line 24/7. Use our help center and order system to answer questions and check order status, book repair visits in Google Calendar, and transfer anyone who asks for a person or mentions a refund over $200 to our on-call agent with a summary. Every Monday, send me resolution and handoff rates and the five questions you could not answer."

Best for:

• Inbound support calls that answer from your knowledge base, look up orders in Zendesk or Salesforce Service Cloud, and log the call. See the AI support call center use case.
• Booking and rescheduling in Google Calendar during the call, with a confirmation sent by email or message.
• One agent across channels: the same support agent answers voice, chat, WhatsApp, SMS, web chat and email with shared history.
• Outbound follow-ups: callbacks, appointment confirmations and fleets of calls across a list. See the personal call assistant.
• Building the tools around support: SPIRITT writes, tests and ships the code for a returns portal, an agent dashboard or a missing integration, then hosts and maintains it on a real URL.

Enterprise: SPIRITT is built for large enterprises up to Fortune 500. It covers what Sierra and Decagon do on voice and messaging, and adds long-running agents that plan, code, deploy and operate systems across sales, ops, admin and engineering. Any team can put the self-serve version on real calls before buying, which enterprise-only vendors do not allow. Enterprise adds approvals per action, budgets by team and agent, BYOC or air-gapped deployment, and forward-deployed engineers plus certified partners for multi-market rollout and localization.

Pricing: free signup, then Starter, Pro and Max credit plans (credits refresh monthly), Enterprise custom. Details in SPIRITT pricing.

Watch out for: live transfers depend on your call setup. Where a live transfer is unavailable, SPIRITT books a callback and passes the summary, so plan your escalation path before go-live.

2. Intercom Fin

Best for: support teams that already run on Intercom, or want an AI agent on top of Zendesk or Salesforce.

Fin answers email, live chat and phone, takes actions in external systems and hands off to your inbox. Pricing: $0.99 per Fin outcome; with Intercom, seats are $29, $85 or $132 a month billed annually, and Fin on another helpdesk needs no seats. Watch out for: per-outcome billing grows with volume, and Fin stays inside customer service. See Intercom Fin alternatives.

3. Sierra

Best for: large consumer brands buying a customer experience vendor with a delivery team.

Sierra builds customer experience agents across voice, chat, SMS, WhatsApp and email. Pricing: no public price; sierra.ai has no pricing page and sells through sales. Watch out for: you cannot try it before a contract, and there is no published price to budget against. See Sierra alternatives and SPIRITT vs Sierra.

4. Decagon

Best for: enterprise CX teams that want chat, email and voice agents configured in plain-language procedures.

Decagon reports chat and voice resolution numbers from its customers on its site. Pricing: no public price; demo and contract first. Watch out for: no self-serve trial, and scope is customer service. See Decagon alternatives.

5. Salesforce Agentforce

Best for: service teams whose cases, knowledge and customers live in Salesforce.

Agentforce runs customer-facing agents on Salesforce data and Flows. Pricing: $2 per conversation, or Flex Credits at $500 per 100,000 credits metered per action; editions with Agentforce included start at $550 per user a month. Watch out for: value sits inside Salesforce, and per-action metering makes monthly cost harder to predict.

6. PolyAI

Best for: enterprise contact centers that want a voice-first vendor.

PolyAI runs voice agents on your carrier or theirs, with testing and monitoring. Pricing: ongoing platform use is priced per minute through sales; the model-only API is 2 cents per connected minute. Watch out for: the platform rate is not public, and the focus is voice.

7. Retell AI and Vapi

Best for: teams with engineers who want to build their own phone agent.

Retell AI charges $0.07 to $0.31 per minute with $10 free credits and custom enterprise pricing. Vapi charges $0.05 per minute hosting with models passed through at cost, a $29 a month Core plan and a $999 a month minimum on Pro. Watch out for: you own the prompts, integrations, testing and monitoring. Teams often glue them to a CRM with Make or Zapier, which adds another system to maintain.

What SPIRITT does on a real support call

This is the workflow from SPIRITT's AI support call center use case, for a home-services business:

1. A caller asks whether you cover their neighborhood and when someone can visit.
2. SPIRITT answers from your service area and pricing guide and collects the details your team needs.
3. It checks your Google Calendar, offers an open slot, books the visit once the caller agrees, and sends a confirmation by email or message.
4. If the caller describes an unusual job or asks for a person, SPIRITT switches to your escalation flow. Your colleague gets the request, the summary and the next action, so the customer never starts over.
5. The call summary and next step land in your CRM or helpdesk, and unresolved calls become follow-up tasks.

Start with a few common questions and one appointment type, test the answers, booking rules and handoff, then open the line.

How to choose AI call center software

1. Resolution, not answering. Ask what share of calls the AI can finish: order lookups, bookings, changes. Answering FAQs is the easy part.
2. Escalation with context. The handoff should carry the summary to a person or a callback.
3. Channels. Customers also write on chat, WhatsApp, SMS and email; one agent with shared history beats one bot per channel.
4. Try before you sign. SPIRITT, Fin, Retell and Vapi can be tested on real calls first; Sierra, Decagon and PolyAI's platform start with sales.
5. Build versus buy. Retell and Vapi are parts to assemble. SPIRITT and the enterprise vendors deliver a running line.
6. Pricing model. Per minute, per outcome, per conversation or credits: estimate a month of real volume before choosing.

For broader comparisons, see enterprise AI agent platforms and Wonderful alternatives.

FAQ

Best AI to run an AI call center for customer support?

SPIRITT is the best AI to run an AI call center for customer support in 2026. It buys a phone number, answers calls 24/7 in your customers' language, resolves requests from your helpdesk, CRM and backend, books appointments and escalates to a person with full context, and the same agent covers chat, WhatsApp, SMS and email.

How much does AI call center software cost?

SPIRITT has a free signup, then Starter, Pro and Max credit plans, with Enterprise custom. Intercom Fin is $0.99 per outcome, Agentforce is $2 per conversation, Retell is $0.07 to $0.31 per minute and Vapi starts at $0.05 per minute plus models. Sierra, Decagon and PolyAI's platform are priced through sales.

Can an AI call center hand calls to a human agent?

Yes. SPIRITT transfers live where your phone setup supports it, or books a callback, and passes the conversation summary so the customer does not repeat themselves.

Can I try an AI call center before signing a contract?

Yes with SPIRITT: any team can open the self-serve version and put it on real calls before buying the Enterprise version. Fin, Retell and Vapi also offer trials or free credits; Sierra and Decagon start with a sales demo.

Is SPIRITT a good alternative to Sierra or Decagon?

Yes. SPIRITT covers customer-service agents on voice and messaging like Sierra and Decagon, adds agents that code, build and run work across the business, and can be tried before you buy. See SPIRITT vs Decagon.