Retell AI

What it does

Retell AI is a platform for building, testing, deploying, and monitoring AI voice and chat agents. Callers reach the agent by phone number, SIP trunk, web widget, or SMS, and the platform handles speech-to-text, a language model that chooses replies using your prompt and tools, and text-to-speech back to the caller. Inputs include prompts or conversation flows, a knowledge base crawled from a website or uploaded documents, and CRM or calendar data. Outputs include live call audio, transcripts, post-call analysis, and outcomes written back to connected systems.

Teams use the no-code dashboard to design call flows, run simulation tests and A/B tests before go-live, and use live monitoring to listen in or take over calls. Developers can manage agents programmatically through the API, SDKs, webhooks, or an MCP server. Common uses listed include lead qualification, appointment booking, customer support, and call transfers to a human with a briefing.

Retell suits teams operating customer calls and developers building configurable conversational services. New accounts receive introductory credits and included concurrent-call capacity, with continuing usage billed for the chosen configuration. Model, voice, telephony and optional features affect the total; silence and hold time can still accrue charges. Teams should test how the agent handles exceptions and transfers, set appropriate data-retention controls and confirm any enterprise requirements before deploying sensitive workflows.

What it can do

• Build voice agents with a single prompt or a drag-and-drop conversation flow with functions, transfers, DTMF, and SMS
• Test agents with simulation testing, manual test calls, and A/B tests before deployment
• Deploy inbound and outbound phone agents, web call widgets, and SMS workflows
• Navigate IVR menus, detect voicemail, and perform warm transfers to human agents
• Monitor live calls and take over when needed, with custom analytics and AI quality assurance across calls
• Use a knowledge base built from crawled websites or uploaded documents

Works with

• Salesforce
• HubSpot
• Microsoft Dynamics 365
• GoHighLevel
• Zoho CRM
• Twilio
• Telnyx
• Vonage
• SIP trunking

Example workflows

Inbound appointment booking

Illustrative example. Input: caller phone call and the clinic's calendar integration. Steps: the agent answers, asks for preferred time and details, checks availability through the connected calendar, and books or reschedules. Output: a confirmed appointment and a call transcript with post-call fields synced to the CRM.

Outbound lead qualification

Illustrative example. Input: an uploaded contact list with CRM records and a qualification script. Steps: schedule an outbound campaign with pacing and retries, the agent asks the qualifying questions, and transfers interested leads to a sales rep with a briefing. Output: qualified leads passed to the rep and call outcomes written back to the CRM.

Before you choose

• Charges accrue per minute for the whole call, including silence and hold time; the telephony fee continues after a transfer while the AI fee stops.
• Pricing varies by chosen LLM, voice, telephony, and add-ons, so cost per minute depends on configuration; use the pricing page estimator.
• Compliance certifications and BAA availability are described on the vendor's site; enterprise terms such as custom BAA and data retention require contacting sales.

Listed under

• Support
• Chat and email agents
• Voice and phone agents
• AI phone agents
• Call center
• Contact center
• Customer service
• Developer platform
• Telephony

Get started

Create an account on the dashboard, which includes $10 in free credits.

1. Create an account at dashboard.retellai.com and open the Playground to test the default agent.
2. Write a single prompt describing the agent's task, then add a knowledge base or integrations as needed.
3. Purchase a Retell phone number or connect an existing number through SIP trunking, then run simulation tests before going live.

Signup includes a one-time $10 credit. Voice rates vary by model and voice, with the page showing $0.07–$0.31/min; review telephony and add-ons separately. Chat starts at $0.002 per AI message. Twenty concurrent-call capacity slots are included, not twenty free calls. Whole-call billing includes silence and hold time; after transfer, AI charges stop but telephony charges can continue.

Source: retellai.com/pricing, checked 29 Oct 2026. Prices can change; check before you buy.

Sources for this overview

Product pages, documentation, and pricing checked 29 Oct 2026. Each source supports part of the overview; availability and prices can change.

• AI Voice Agents That Automate Phone Calls | Retell AI ↗www.retellai.com
• AI Phone Agent Pricing | Retell AI ↗www.retellai.com
• Retell AI: build, test, deploy, and monitor voice & chat agents ↗docs.retellai.com

Company website

retellai.com: product, pricing and policy pages

Hacker News

Launch posts and discussion

YC directory mirror

Batch and company name

Web search

Confirms the official site

Social accounts

Accounts the company links, and its posts on X

Human review

Checked by a person

knowledge_base

Last checked 29 Oct 2026. Every field keeps its source and date; unknown means we couldn’t confirm it.