Retell AI
Developer platform for building, deploying, and monitoring voice agents
Best for
Best for engineering teams building production voice agents who need turn-taking quality and low-level workflow control
At a glance
- Pricing
- paidfrom $0.07/mo
- Setup time
- 1 hour
- Learning curve
- medium
- Last verified
- 5/21/2026
What we love
- ✓Best-in-class interruption handling
- ✓Bring-your-own-LLM keeps costs flexible
- ✓HIPAA path is rare in this category
Where it falls short
- −Less polished no-code UI than competitors
- −Smaller voice library than dedicated TTS shops
- −Docs sometimes lag feature releases
Pricing
✓ Pricing verified Jun 21, 20262 tiers
Pay-as-you-go
per call minute
- ✓All voices
- ✓API access
- ✓Standard support
Scale
annual contract
- ✓Volume discount
- ✓Priority support
- ✓HIPAA BAA
- ✓Dedicated infra
Why we picked it
Retell's turn-taking model is the secret sauce — most voice agents talk over users or freeze on interruption. Retell handles it like a real call.
Overview
Retell AI is a developer-focused voice agent platform that combines a turn-taking engine, low-latency LLM orchestration, and built-in telephony. The retell-engine handles interruptions and barge-in better than most, which matters once you're running thousands of live calls. Y Combinator-backed and widely used in healthcare, real estate, and SMB outbound.
Key features
- ●Turn-taking model with barge-in handling
- ●Hosted telephony or BYO Twilio
- ●LLM-agnostic routing (GPT, Claude, custom)
- ●Knowledge base attachment
- ●Live monitoring and call analytics
- ●Webhooks for function calls
- ●HIPAA-eligible plans
Best use cases
Patient intake
Run HIPAA-compliant intake and appointment booking calls with EHR integration.
Lead qualification
Place outbound qualification calls with live transfer to human AEs on hot signals.
Integrations
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