Retell AI vs Vapi: pricing, features and which to choose

Retell AI began as a five-person team accepted into Y Combinator in November 2023, then launched publicly in February 2024 through Hacker News and Product Hunt. The company raised a $4.6 million seed round in May 2024, backed by Alt Capital and angel investors; TechCrunch reported $4.53 million raised and hundreds of paying customers that month. Retell’s platform lets businesses build voice agents for phone and web conversations, with templates, APIs, transcripts, analytics, webhooks, simulation tools, and transfers. Its pay-as-you-go plan has no platform fee or minimum commitment, lists voice pricing at $0.07 to $0.31 per minute, and includes 20 concurrent calls. Retell later reported $40 million in annualized revenue in 2025 with a 25-person team, followed by $80 million by December 2025.

A typical Retell workflow begins with a prebuilt template or new agent, followed by configuration of prompts, conversation flows, knowledge sources, tools, transfers, voice settings, and language models. Teams can connect a web call or phone number, then review behavior in Playground, simulation, batch, web, or phone tests. Text tests are billed per message, while web and phone tests use applicable production rates. Before launch, developers can test webhook and custom-function payloads, configure fallback behavior, and revise agent versions. In production, call transcripts, analytics, filters, alerts, and quality tools support monitoring. Agents can also hand calls to staff, use knowledge bases, send SMS, and apply safety guardrails. Retell’s platform supports GPT, Claude, Gemini, ElevenLabs, Cartesia, and other voice or model options.

Retell AI’s main limitation is cost complexity: its $0.07 to $0.31 headline range excludes some telephony and add-on charges, and testing is billed at production rates rather than through a free sandbox. Vapi is a strong alternative for developer-led voice orchestration, while Bland AI offers a more focused phone-agent product; ElevenLabs Conversational AI may appeal more to teams prioritizing voice quality, since TechCrunch’s 2024 test found Retell’s synthetic voice less realistic than ElevenLabs and OpenAI’s. Retell counters with broader workflow tooling, including simulations, webhooks, analytics, transfers, versioning, guardrails, and 20 included concurrent calls. Its enterprise plan adds custom terms, SSO, access controls, and dedicated support, but requires a sales process. Pick Retell for configurable production workflows and metered experimentation, not flat pricing or self-hosting.

Vapi is a San Francisco company that sells the plumbing behind AI phone agents. Jordan Dearsley and Nikhil Gupta, classmates from the University of Waterloo, went through Y Combinator with a productivity app called Superpowered. In 2023 Dearsley built an AI therapist to talk to on walks, found that startups wanted the low-latency voice layer underneath it, and the pair relaunched as Vapi in 2024. In May 2026 it raised a $50 million Series B led by Peak XV at about a $500 million valuation, bringing total funding to $72 million, according to TechCrunch. The company says it has handled more than 1 billion calls and has over 1 million developers on its self-serve platform. Enterprise customers include Amazon Ring, which routes all of its inbound support calls through Vapi, plus Intuit, New York Life and Kavak.

A Vapi agent is a configuration that wires together three parts: a transcriber that turns caller speech into text, a language model that decides what to say, and a voice that speaks the reply. You set these up in the dashboard or through the API, write a system prompt, and attach tools so the agent can book appointments, look up orders or transfer to a human. Vapi supplies phone numbers, or you bring your own through Twilio, Vonage or SIP. Squads let several specialised agents hand a call to each other. Testing and simulation features run scripted calls against an agent before it reaches customers, and observability dashboards flag failed calls. Web and mobile SDKs cover in-app voice. Common uses are customer support lines, lead qualification, appointment scheduling and outbound sales calls.

Vapi expects you to write prompts, configure tools and read logs, so non-technical teams usually need a developer or an agency to get an agent into production. Total cost is harder to predict than a flat per-minute rate because it depends on which models you pick. Retell AI offers a similar developer platform with simpler bundled pricing and strong turn-taking, and Bland AI targets enterprises that want a more managed service with its own hosted models. ElevenLabs Agents is the easier choice if you already use ElevenLabs voices and want one vendor. Pick Vapi if you have engineers, expect high call volumes and want freedom to change speech, language and voice providers as models improve. Choose Retell or a no-code tool if your team wants a working receptionist this week without touching an API.