Last updated: 2026-07-01
Retell AI is a voice AI platform that has processed over 50 million AI phone calls, connecting speech recognition, a large language model, and text-to-speech into one real-time pipeline for inbound and outbound call automation. Unlike single-stack competitors, it lets developers choose their own LLM and voice-engine providers for each deployment.
About Retell AI
Retell AI is a voice agent platform founded in 2023 in New York by Bing Wu, Evie Wang, Zexia Zhang, Todd Li, and Weijia Yu. The company is backed by $5.1M in seed funding from Y Combinator (W24 batch), Alt Capital, Carya Venture, and angel investors including the co-founders of Lyft, Box, and Twitch, and has grown to a team of 25 serving clients across healthcare, financial services, insurance, logistics, and retail. The core product assembles speech-to-text, a large language model, and text-to-speech into a single real-time voice pipeline for inbound and outbound calls. Rather than locking teams into one vendor, it exposes each stage of that pipeline for independent selection, and developers can build custom workflows with SDKs alongside a no-code conversation flow builder for non-engineers, giving full control over the quality-versus-cost trade-off that a fixed-stack platform does not allow.
Pricing
Usage-based: $0.07+/minute for voice engine, plus LLM ($0.003-$0.08/min) and telephony ($0.015/min). All-in realistic rate: $0.085-$0.19/minute. $10 free credits on signup. 20 concurrent calls included; additional at $8/line/month. Enterprise discounts from $0.05/min for accounts over $3,000/month.
Key Features
- 600ms End-to-End Latency: Delivers voice responses in as low as 600 milliseconds from the end of caller speech, avoiding the awkward pauses that make phone bots sound robotic.
- Component-Based LLM and Voice Selection: Lets developers pick their LLM (GPT-4.1, Claude, or others) and voice engine (ElevenLabs, Cartesia, MiniMax, OpenAI) independently, trading cost against quality for each deployment.
- No-Code Conversation Flow Builder: Provides a node-and-transition flow editor for structured call scripts, letting non-engineers build branching inbound and outbound agent workflows without writing code.
- Outbound Batch Campaigns: Runs high-volume outbound call campaigns without concurrency limits, with voicemail detection, real-time CRM record updates, and per-call conversion tracking.
- Multilingual Voice with Auto-Detection: Automatically detects the caller's language and switches among dozens of supported languages, letting a single agent deployment serve multilingual audiences without separate configurations.
- HIPAA and SOC 2 Compliance: Meets HIPAA, SOC 2 Type II, and GDPR requirements with PII redaction, encrypted transcripts, and audit-ready data processing agreements for regulated-industry deployments.
Pros
- G2 rating of 4.8/5 across 1,414 reviews, with 93% five-star ratings and recognition as G2 Best Agentic AI Software for 2026, the highest user-satisfaction score in the AI voice agent category.
- Multi-provider architecture lets teams mix and match LLMs and voice engines, giving cost control that single-stack competitors like Bland AI or Vapi cannot match at the component level.
- HIPAA, SOC 2 Type II, and GDPR compliance out of the box, enabling healthcare and financial services deployments without additional infrastructure work.
Cons
- Component-based pricing makes total cost hard to predict up front: real invoices commonly land 30-60% above the headline per-minute rate once LLM and telephony fees are added.
- Voice quality for non-English calls, particularly German, has drawn complaints: 67 G2 reviewers specifically cited issues with international language support.
- No zero-code onboarding path: building production agents requires developer involvement for LLM selection, telephony configuration, and SDK integration, which limits adoption by non-technical teams.
Frequently Asked Questions
How much does Retell AI cost in 2026?
Retell AI charges $0.07+/minute for the voice engine with no platform fee, plus separate costs for the LLM ($0.003-$0.08/minute) and telephony ($0.015/minute), which bring the realistic all-in rate to $0.085-$0.19/minute. Twenty concurrent calls are included free, with additional lines at $8/line/month, and enterprise accounts spending $3,000+/month receive volume discounts to about $0.05/minute.
Is Retell AI free to use?
There is no ongoing free tier, but new accounts get $10 in free credits and 20 concurrent calls at no charge, enough for roughly 140 minutes of testing at the base rate. Usage-based billing begins automatically once the credits run out.
What are the best alternatives to Retell AI?
Bland AI offers simpler flat per-minute pricing that is easier to budget than Retell's component-based model. Vapi targets developers who want similar multi-provider flexibility but with a smaller user community. Twilio Voice suits teams that want raw telephony infrastructure and plan to build their own voice AI stack from scratch rather than use a managed platform.
How does Retell AI compare to Bland AI in 2026?
Retell's multi-provider architecture lets teams choose their LLM and voice engine independently, while Bland AI runs a fixed stack with simpler, more predictable per-minute billing. Retell publishes explicit HIPAA and SOC 2 Type II compliance documentation, which matters for healthcare and financial-services deployments, while Bland AI's compliance posture is less prominently documented. For regulated-industry call automation, Retell is the stronger pick.
How do you get started with Retell AI?
Sign up on retellai.com to claim the signup credits and included concurrency, then choose an LLM and voice engine in the dashboard or use the no-code flow builder to sketch a call script. Developers wire up custom logic with the Node.js or Python SDK and connect a phone number through the built-in Twilio or Vonage integration before going live.
Top Alternatives
- echowin: Pick echowin if you want a no-code phone receptionist ready to go for a small business; pick Retell AI if you need a developer-controlled voice pipeline with your own choice of LLM and TTS provider.
- Rootle: Pick Rootle if your call volume is concentrated in Indian-language markets and you want a no-code setup; pick Retell AI if you need HIPAA and SOC 2 Type II compliant infrastructure for regulated industries.
HokAI guides covering Retell AI
- Best AI Voice Assistants in 2026: A Buyer's Guide to Synthesis, Transcription and Agents: AI voice assistants split into three buying decisions: synthesis, transcription and agent orchestration. Compare ElevenLabs, Deepgram and Retell AI for 2026.