> ## Documentation Index
> Fetch the complete documentation index at: https://docs.closethecall.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Voice Providers Explained

> Understanding VAPI, Retell, and Bland — which one powers your AI and why it matters

## What Is a Voice Provider?

A voice provider is the **AI engine that handles phone calls**. It listens to the caller, thinks of a response, and speaks back in a natural voice. Think of it as the "brain" behind your AI receptionist.

The voice provider is separate from the phone number. The phone number is how callers reach your AI. The voice provider is what answers and talks.

***

## For Direct Clients

<Info>Your provider is managed by the platform. You do not need to choose or configure anything — it just works. The platform uses VAPI by default, which gives you the best feature set including appointment booking, lead capture, and caller intelligence.</Info>

***

## For Agencies

You choose which voice provider to use for all your clients. Set this in **Agency Settings > API Keys** by entering the API key for your chosen provider.

See [API Keys & Voice Providers](/agency/api-keys-providers) for setup instructions.

***

## The 3 Providers

### VAPI (Recommended — Default)

VAPI is the most popular AI voice platform and the default provider on CloseTheCall. It offers the richest feature set of any provider.

* **Voices:** ElevenLabs premium voices (Sarah, Alice, Eric, Daniel), VAPI native voices, custom voice clones
* **Phone numbers:** US only (native provisioning). UK, AU, and other countries require Twilio — see [Twilio Setup](/integrations/twilio-setup)
* **Key features:** Function calling (book appointments, capture leads), knowledge base RAG, Squads (multi-assistant routing), voicemail detection, caller intelligence (greet returning callers by name), bilingual support (5 languages), call transfer to human
* **Pricing:** Varies by voice and LLM selection. Check [vapi.ai](https://vapi.ai) for current rates.
* **Best for:** Most businesses. Richest feature set, best AI quality.

### Retell

Retell is a high-quality conversational AI platform with low latency and simpler setup.

* **Voices:** Retell native voices, custom voice options
* **Phone numbers:** Native provisioning for multiple countries — no Twilio needed for UK, AU, or EU numbers
* **Key features:** Agent creation, custom voices, call transfer, basic call handling
* **Pricing:** Varies by usage. Check [retell.ai](https://retell.ai) for current rates.
* **Best for:** Agencies wanting simpler setup with native international numbers without the Twilio hassle.

### Bland

Bland is a budget-friendly voice AI option designed for high-volume deployments.

* **Voices:** Bland native voices
* **Phone numbers:** Native provisioning for multiple countries — no Twilio needed
* **Key features:** Basic AI agents, call handling, simple conversation flows
* **Pricing:** Varies by usage. Check [bland.ai](https://bland.ai) for current rates.
* **Best for:** High-volume, cost-sensitive deployments where advanced features are not required.

***

## Comparison Table

| Feature                                      | VAPI                             | Retell                               | Bland                              |
| -------------------------------------------- | -------------------------------- | ------------------------------------ | ---------------------------------- |
| Voice quality                                | Premium (ElevenLabs)             | High                                 | Good                               |
| Phone numbers (US)                           | Native                           | Native                               | Native                             |
| Phone numbers (UK/AU/EU)                     | Needs Twilio                     | Native                               | Native                             |
| Multi-assistant routing (Squads)             | Yes                              | No                                   | No                                 |
| Knowledge base RAG                           | Yes                              | No                                   | No                                 |
| Function calling (book appts, capture leads) | Yes                              | Limited                              | Limited                            |
| Caller intelligence (greet by name)          | Yes                              | No                                   | No                                 |
| Voicemail detection                          | Yes                              | Basic                                | No                                 |
| Bilingual support                            | Yes (5 languages)                | No                                   | No                                 |
| Cost                                         | Check [vapi.ai](https://vapi.ai) | Check [retell.ai](https://retell.ai) | Check [bland.ai](https://bland.ai) |

***

## Which Should You Choose?

<CardGroup cols={2}>
  <Card title="I want the best AI quality and most features" icon="star">
    **Choose VAPI.** It has function calling, knowledge base integration, caller intelligence, voicemail detection, and bilingual support. Most CloseTheCall features are built on VAPI.
  </Card>

  <Card title="I need international numbers without Twilio" icon="globe">
    **Choose Retell.** It provisions phone numbers natively in multiple countries, so you skip the Twilio regulatory setup entirely.
  </Card>

  <Card title="I want the lowest cost per minute" icon="coins">
    **Choose Bland.** It is the most affordable option for simple call answering at scale. Check their website for current rates.
  </Card>

  <Card title="I am a direct client and do not care" icon="circle-check">
    **Do not worry about it.** The platform handles everything for you. Your AI receptionist uses VAPI by default and it just works.
  </Card>
</CardGroup>

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