Retell AI vs Vapi: which voice agent platform suits your business

Retell AI vs Vapi comes down to how much you want packaged for you. Retell bundles more into one per-minute price and gives non-technical staff a no-code studio, while Vapi charges a small platform fee and passes through the cost of each provider you choose, which gives a developer more control and more parts to manage.

Both are platforms for building AI phone agents, not finished receptionists. Someone still has to write the agent, connect it to your calendar and CRM, test it and keep it working. CentriWeb builds and looks after voice agents for clients, on platforms of this kind, so weigh our view with that in mind. Every fact below comes from Retell’s and Vapi’s own pages as at November 2026; check their pages for current prices.

Retell AI vs Vapi at a glance

How each one bills

Retell: one bundled rate, built from parts

Retell’s pricing page lists pay as you go voice agents at $0.07 to $0.31 a minute, depending on the voice and language model you pick. The parts it lists include $0.055 a minute for its voice engine and $0.015 a minute for telephony in listed countries. Its own worked example comes to $0.11 a minute before telephony and add-ons.

Other points from the same page:

• New accounts get $10 in free credits, with no minimums or contracts.
• 20 concurrent calls are included. Extra capacity is $8 per concurrent call per month.
• Calls are billed to the second, and silence and hold time are billed.
• Add-ons such as a knowledge base, denoising and PII removal add a fraction of a cent to a cent a minute each.

Vapi: a platform fee plus what each provider charges

Vapi’s pricing page lists $0.05 a minute for Vapi hosting, then passes through the cost of the transcriber, language model and voice at cost, with no markup. Telephony is charged by whichever carrier you use. You can start at $0 with $5 of free credit, and a Core package is listed at $29 a month.

Concurrency is lower at the entry level: 4 concurrent calls with no package, 10 on Core, and $10 a month for each extra line. Vapi’s own calculator shows an estimated $82 to $129 a month for 1,000 minutes.

The figures are shown as dollar amounts on pages written for a US audience, so confirm the currency before you budget. Our guides to Retell AI pricing and Vapi pricing walk through a full month’s bill for each.

What you still have to build on either platform

Neither platform knows your business on day one. On both, the work that decides whether callers are happy is the same list:

1. The script and prompt. What the agent says, what it must never say, and when it hands over. Our guide to writing an AI receptionist script covers this.
2. Your information. Services, service areas, hours, pricing rules and the questions people actually ask.
3. Calendar and CRM connections. Booking into the real diary and writing the caller’s details where your team will see them.
4. Transfers. Who gets the call when the agent should stop, and what happens when nobody answers.
5. Testing. Calls in your own accent, with background noise, interruptions and awkward questions.

How each platform helps with that list differs.

• Retell’s documentation describes two agent types: a single prompt, and a conversation flow split into nodes for tighter control. It lists built-in CRM sync for Salesforce, HubSpot, Dynamics 365, GoHighLevel and Zoho, warm transfers, webhooks, simulation testing and A/B testing between prompts.
• Vapi’s documentation is built around assistants (a system prompt plus tools) and squads (several assistants handing over with context). Tools connect the agent to your APIs and databases, and simulations test a setup before customers call. A CLI and config-as-code suit a developer who wants agents in version control.

Phone numbers in your country

This matters more outside the United States and Canada than most comparisons let on. Retell’s number guide says it sells only US and Canada numbers, and points you to your own telephony provider for other countries. Vapi’s phone calling guide says its free numbers use US area codes and are inbound only, and that international or outbound use needs a number imported from Twilio, Telnyx, DIDWW or a SIP trunk.

So on either platform, a business outside those countries will usually bring its own number through a carrier, which is one more account and one more bill to look after. Check that your carrier supports the connection before you build.

Where each one is strong

Retell AI

• Fewer decisions to make: the voice engine, model and voice are chosen from one menu and billed together.
• A no-code studio that the Retell homepage says a customer service team can work in, with developers extending it.
• Higher included concurrency (20 calls), which matters if calls arrive in bursts.
• Compliance claims on its own homepage, including HIPAA and SOC 2 Type 1 and Type 2, which some health businesses will need to check.

Vapi

• Choice of each component, with provider costs passed through at cost.
• A small platform fee, which suits a team that already pays providers directly.
• Squads for handing a caller between specialised assistants.
• Developer tooling (CLI, SDKs, config-as-code) that fits a team already shipping software.

Who maintains it six months in

The launch is the easy part. Over the following months, your prices change, a staff member leaves, the calendar tool updates its connection, and callers find questions nobody planned for. Someone has to read call transcripts, fix the prompt and retest.

With Retell, that person can be a capable office manager for prompt changes, with a developer called in for integrations. With Vapi, the maintainer is more often a developer, because more of the setup lives in tools, API calls and provider accounts. Before you pick, name the person who will do this work each month. If you can’t, that’s a sign to look at how the agent will be looked after before you look at features. Another platform often set beside Retell AI is covered in Bland AI vs Retell AI.

When a built and looked after system fits better

A self-serve platform is a good choice if call volume is low, an owner or staff member has the time and interest to run it, or the standard setup does the job. Plenty of businesses fit that description, and they don’t need anyone else involved.

A system built and looked after for you suits a business where missed calls cost real money, where the agent must book into a live calendar and write to the CRM every time, and where nobody on staff wants to read transcripts and fix prompts. That’s the work our AI phone and chat agents service covers, and why we often start with how calls are handled now before choosing a platform. If you’re weighing doing it yourself, our guide on whether to build a voice agent yourself or have one built sets out both paths.

How to choose

1. Write down what the agent must do: answer questions, book jobs, take messages, transfer, or call people back.
2. Estimate monthly minutes and your busiest hour, then price both on their own calculators.
3. Check how you’ll get a number from your own country onto the platform.
4. Name the person who will maintain it and ask them which builder they can work in.
5. Build the same simple agent on both with the free credits and call each one yourself.