Vapi vs Retell AI for Business Voice Agents: Pricing, Control, and What to Test

Two Strong Options for Different Teams

Vapi and Retell AI are two of the most widely used platforms for building AI phone agents. Both can power receptionists, booking agents, lead qualification, and support lines. The right choice depends less on which is "better" and more on your team, your compliance needs, and how you want to pay.

Figures below are from each vendor's pricing page in October 2026. Prices change often, so confirm them before deciding.

How Each One Charges

Vapi lists a hosting fee of $0.05 per minute. On top of that, you pay for the providers you choose: speech-to-text, the AI model, the voice, and telephony. Vapi passes model and voice provider costs through at cost. Optional plans add support and discounts, including a $29 per month Core plan and a Pro plan with a $999 monthly minimum.

Retell AI lists a price for each component: $0.055 per minute for voice infrastructure, $0.015 to $0.040 per minute for text-to-speech depending on the voice provider, a per-minute rate for the AI model you choose, and telephony. The vendor puts the total at $0.07 to $0.31 per minute.

A Rough Per-Minute Comparison

Using the published rates, a typical configuration with a mid-priced AI model and voice works out roughly as follows:

These are estimates from listed rates, not quotes, and your real cost depends on model, voice, call length, and telephony. For a business taking 2,000 minutes of calls a month, both platforms typically land in the low hundreds of dollars a month in usage, which matters less than whether the agent books correctly. See our voice AI agent pricing guide.

Concurrency

How many calls can run at once matters during rushes:

• Vapi: 4 to 30 concurrent calls depending on plan, with additional lines at $10 per line per month.
• Retell AI: the first 20 concurrent calls are included, with more at $8 per concurrency per month.

HIPAA and Compliance

• Vapi: HIPAA compliance is an add-on listed at $2,000 per month, including a BAA. Its top tier adds role-based access, zero data retention, and SSO.
• Retell AI: lists HIPAA with BAAs, SOC 2 certification, and custom DPAs. Confirm which plan includes a BAA for your use.

For healthcare, this difference can decide the choice on cost alone. See our HIPAA-compliant AI receptionist guide.

Developer Control and Day-to-Day Operations

Vapi is a developer platform. It gives fine control over every component and suits teams that want to swap providers, tune latency, and integrate deeply through APIs and tools.

Retell AI offers flexible agent tooling with a strong focus on conversation flow and a more packaged experience, while still supporting custom functions and integrations.

Either way, ask how your team will:

• Test a change before it reaches live callers
• Review transcripts and failed calls
• Version prompts and roll back a bad update
• Get alerted when an integration fails

A Test Plan for Choosing

1. Define one call journey, such as new patient booking, from greeting to confirmed appointment.
2. Build it on both platforms with the same instructions, voice style, and integrations.
3. Run the same 20 test calls on each, including interruptions, unclear answers, a taken time slot, a transfer request, and background noise.
4. Score each on task completion, natural pacing, mistakes, and transfer quality.
5. Price the configuration you actually used, at your expected monthly minutes and peak concurrency.
6. Pick the winner for this use case, and pilot it on live calls.

When We Lean One Way or the Other

• Lean Vapi when you need maximum control over providers, plan deep custom integrations, or want to optimize cost per minute at scale.
• Lean Retell AI when you want clear component pricing, included concurrency, and compliance options such as BAAs without a large add-on fee.

Bottom Line

Both platforms can run a production phone agent. Decide with your own test calls, your compliance requirements, and a price based on your real configuration. For a broader view, see Vapi vs. Retell AI vs. Bland vs. Synthflow. We build on both; see our Vapi and Retell AI implementation services.