by Retell AI · founded 2023 · updated Aug 2026
Retell AI is a developer-friendly platform for autonomous phone and voice agents: build, test and deploy AI that answers calls, books appointments and resolves issues. Pay-as-you-go pricing from ~$0.07/minute (plus LLM and telephony) and production deployments in 2–9 days make it the fast, transparent entry into voice AI.
Fixed weights, sources attached, the formula
Each score is built from the claims below. This is a snapshot, so check the current terms with the vendor before you commit to anything.
All 4 claims below are past their re-check window. Pricing, availability and security details move fast, so confirm those with the vendor.
| Claim | Source | Checked |
|---|---|---|
| Medical Data Systems runs 100% of inbound debt-collection calls on Retell: ~30% transfer rate, ~$280K/month automated collections activity· re-check | Retell AI case studies | Jul 2026 |
| Self-service HIPAA BAA included without enterprise-tier gating· re-check | Retell AI compliance docs | Jul 2026 |
| Pay-as-you-go voice platform from ~$0.07/min plus model and telephony costs· re-check | Vendor pricing pages | Jun 2026 |
| Enterprise tier now starts at $8,000 with white-glove managed setup; per-minute range widened to $0.07-$0.31 with newly added GPT-5.x and Claude 4.5/4.6 Sonnet model support plus a Fast Tier LLM option at 1.5-2x standard rates· re-check | Vendor pricing pages | Aug 2026 |
Rime, which fields calls with voice models trained on studio-recorded conversational data, raised a $24M Series A led by M13. More capital chasing contact-centre voice quality, specifically naturalness on collections and support calls.
xAI launched a Voice Agent Builder that spins up production voice agents in under two minutes with no code, priced at $0.05/min of audio plus $0.01/min telephony. More price pressure on voice-agent platforms. Retell is the obvious thing to benchmark it against on high-volume outbound.
Sierra's Series E (led by GV and Tiger Global) pushes total funding past $1.5B on ~$200M ARR. Its agents now run revenue-cycle workflows between providers and payers and process insurance claims. Healthcare collections and RCM buyers should have it on the list.
New governance products operationalize real-time TCPA, DNC and TSR compliance across collections and regulated outreach, a response to AI voice agents scaling in debt recovery. If you run AI collections calls, a documented consent-and-suppression control layer is now table stakes.
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