Retell vs Vapi
Two of the most-shipped programmable voice platforms in 2026. We've benchmarked both inside paid Diagnostic engagements — here's the honest read, from a vendor-neutral advisor.
Retell and Vapi are the two names that show up in almost every AI voice shortlist we audit. Both are developer-first platforms — you bring the orchestration ideas, they handle the realtime voice stack. Neither ships as a packaged receptionist; both can become one with two to four weeks of integration work.
We've shortlisted both inside paid Diagnostics across ANZ healthcare networks (110+ clinics, 7.2M minutes/year on the platform our largest engagement runs). The comparison below distils where each one actually wins — without affiliate fees, without resale margin, without a preferred-vendor relationship.
Scorecard — Retell vs Vapi
Reliable sub-second turn-taking from Sydney/Melbourne; very consistent in steady state.
Slightly better first-token in our test calls; comparable steady-state latency.
Opinionated TTS set; good defaults, less room to tune persona per use-case.
Multi-provider TTS routing — pick ElevenLabs / PlayHT / Cartesia per persona. More work, better ceiling.
Visual conversation flow editor. The most accessible in the category — non-engineers can review and edit.
Squad / function-call pattern. Powerful for engineers; steeper for clinical or business reviewers.
Simpler per-minute pricing; modestly higher at scale (>100k mins/mo).
Provider-pass-through. More moving parts; lower floor when you optimise STT/TTS routing.
2–3 weeks to a working pilot for a 2-person team. The visual editor pulls weight here.
3–4 weeks typical. Worth it if voice tuning or warm-transfer-with-summary matter.
Works; less mature than Vapi for context-preserving handoff with summary.
Mature warm-transfer + transcript-summary pattern. Matters for after-hours triage.
Product-grade dashboard, analytics, transcript search.
Strong logs + assistant trace; excellent for QA cycles.
BAA available; US-hosted by default. Partner-built overlay required for AU Privacy Act residency.
BAA available; same shape. Both clear board review with the right DPA + overlay.
Teams with non-engineer reviewers; time-to-pilot is the constraint.
Engineering teams who want maximum control over voice and transfer flows.
What we'd pick for an ANZ healthcare network
- — Clinical, ops or compliance reviewers need to read and edit the conversation flow themselves.
- — Time-to-pilot is the dominant constraint and a 2-person team is shipping.
- — You want the simplest unit economics conversation when finance asks.
- — You need fine-grained control over TTS provider, voice persona, or per-step model routing.
- — Warm-transfer-with-summary to an on-call human is a hard requirement (triage, after-hours, escalation).
- — Your engineering team owns voice end-to-end and wants the thinnest, most composable platform layer.
Retell wins on speed-to-pilot and reviewer ergonomics; Vapi wins on voice tunability and transfer maturity. Neither replaces the integration work into your CRM, PMS, or system of record — that sits on you or your partner. For ANZ healthcare specifically, we've shortlisted both successfully; the deciding factor is usually who's reviewing the flows, not who's coding them.
FAQ
Which is cheaper — Retell or Vapi?
Depends on volume and tuning. At small scale (<50k minutes/month) the numbers are within ~15% of each other. At higher volume, Vapi's pass-through pricing lets you optimise the STT/TTS layer for a lower floor — but only if you have the engineering bandwidth to tune it. Retell's simpler per-minute model is what most networks actually pay, because that engineering tuning rarely happens.
Which is easier to ship for a 2-person team?
Retell. The visual flow editor removes most of the orchestration code. A 2-person team typically ships a working pilot on Retell in 2–3 weeks; Vapi adds a week to that timeline in exchange for more headroom later.
Is Retell HIPAA compliant? Is Vapi?
Both offer a BAA and can be deployed in a HIPAA-compliant configuration. Neither is 'compliant' as a stand-alone product — compliance is the configuration around it. For ANZ, both can be configured to meet the Australian Privacy Principles with a partner-built AU-residency overlay. See our deeper write-up: Is Retell AI HIPAA compliant?
Which has better Australian accent handling?
Vapi, narrowly — because you choose the TTS provider. ElevenLabs and PlayHT both have strong AU voices that you can plug straight in. Retell's defaults are good for AU/NZ but less tuneable.
Which one would Cadence shortlist for a multi-site GP network?
Both make our shortlist regularly. The deciding factors are: (1) who's reviewing the flow — clinical SME vs engineer; (2) whether warm-transfer-with-summary is a hard requirement; (3) what the existing engineering bandwidth looks like. We run the actual scoring inside a paid 2-week Diagnostic.
Are you reselling either platform?
No. Cadence is the independent advisor — we take no referral fees, no resale margin, no preferred-vendor kickback from either Retell or Vapi (or any other platform). We score against the CAPR framework, recommend, and run the deployment.
Want the picked-for-you answer in 2 weeks?
The 2-week paid Diagnostic runs the full 8-domain CAPR scorecard against your network's call profile, PMS and compliance posture. You leave with a named pick.