Retell AI

Retell AI is a voice and chat AI platform that helps businesses deploy human‑like phone agents and conversational assistants without complex infrastructure. It provides pay‑as‑you‑go pricing, customizable voices, and multi‑LLM orchestration, making it easier for companies to automate customer support, appointment scheduling, and lead qualification. Designed for startups, healthcare providers, and enterprise teams, Retell AI reduces the complexity of building voice agents by offering pre‑built templates and drag‑and‑drop call flow design.

The platform includes real‑time function calling, streaming RAG for knowledge base sync, and ultra‑low latency (~600ms) to ensure natural conversations. Retell AI also supports HIPAA compliance, PII redaction, opt‑out recording, and enterprise‑grade safety guardrails, alongside integrations with Twilio, Telynx, and major CRMs. Businesses can choose from multiple LLMs such as GPT‑5.5, Claude 4.6, and Gemini 3.5, and pair them with text‑to‑speech voices from providers like ElevenLabs and OpenAI. These features help organizations scale customer interactions, reduce costs, and deliver consistent service quality across inbound and outbound calls.

And the best part? Retell AI offers free credits on sign‑up, allowing businesses to test the platform immediately without contracts. Paid usage is billed per minute for voice agents and per message for chat agents. Enterprise plans unlock unlimited concurrent calls, dedicated servers, and 24/7 support, making Retell AI flexible for both small pilots and large deployments.