Retell AI vs Vapi: Which Should You Use to Build Voice Agents?

Retell AI and Vapi both let you build an AI agent that makes and answers real phone calls. We've published full builds on both: a dental assistant on Retell and a first assistant on Vapi. Our own client systems currently run on Retell, so factor that in as you read.

The quick comparison

Prices were checked on Retell's and Vapi's pricing pages on 4 November 2026.

Where Retell AI wins

Faster to a working phone agent. Retell feels like one product. The voice, model and phone settings all live in one place, and that matters when a client is waiting on you.

Simpler billing for clients. Costs appear in one bill, so it's easier to explain to a client and to build into your retainer.

More room to grow on the entry tier. With 20 concurrent calls included at no plan cost, you can run a batch of outbound calls or a busy inbound line without upgrading.

Where Vapi wins

More control. Vapi is built around choosing each provider yourself: transcriber, model, voice and telephony. If you want to tune each piece, it's the better fit.

Pass-through provider costs. Vapi says models pass through with no markup, so careful teams can tune costs closely.

Developer-first workflow. If you think in APIs and want agents defined in code, Vapi will feel natural.

What about latency and call quality?

Published comparisons disagree. Different reviews rank each of them as faster, and many of those reviews come from companies selling something. The results depend heavily on which model, voice and region you pick, so a table can't settle it.

The honest test takes an afternoon. Build the same short script on both, using the same model and a similar voice. Call each one ten times from a normal mobile, and interrupt it mid-sentence. Then pick the one that sounds better to you.

Which should you choose?

Pick Retell if:

• You're selling to clients and want them live quickly.
• You aren't a developer, or you want to spend your time on sales.
• You'll run outbound batches and need concurrency without extra fees.

Pick Vapi if:

• You or your team are comfortable with APIs.
• You need a specific provider combination.
• You want tight control over each cost line.

For most people starting an agency, we'd begin with Retell. It removes decisions at the stage when your real problem is getting a first client, not tuning the stack. You can always move later, since your prompts and call scripts carry over.

Whichever you choose, the real work is the same

The platform is only one part of a sellable system. Clients pay for what surrounds it:

• A script that handles interruptions and odd questions.
• CRM or sheet updates during the call, usually through n8n or Make.
• Booking and a clean handover to a person.
• Recordings and reports that prove the value.

Want to know what this costs in practice? See our breakdown of AI voice agent costs, including real spend from our own calls.

Frequently asked questions

Is Retell AI or Vapi cheaper?

They're close. Vapi's calculator estimates $82 to $129 per 1,000 minutes. A mid-range Retell setup comes to about $110 per 1,000 minutes. Your choice of model and voice affects the total more than the platform does.

Which is better for beginners, Retell AI or Vapi?

We think Retell is easier for beginners and non-developers, because more of the setup is bundled in one place. Vapi rewards people who are comfortable with technical configuration.

Can I use Retell AI or Vapi with n8n?

Yes. Both can connect to n8n and Make through webhooks and custom functions. That's how an agent can look up a lead or update a CRM during a call.

Do Retell AI and Vapi support Arabic?

Language support depends on the transcriber, model and voice you select, and it changes often. Test real Arabic calls in your target dialect before promising this to a client.