Request for information regarding the use and deployment of Retell AI

Hello,

I am reaching out to you to request some information about your platform.

I am a developer based in France, and my goal is to design AI voice agents and chatbots for commercial use by French companies. These agents would be used, in particular, to manage calendars, customer profiles, incoming inquiries, and automated reminders.

With this in mind, I would like to better understand how the commercial deployment of these agents is organized. Is it necessary to create a separate account for each client company in order to transfer the developed agent to them, or is it possible to maintain a single account from which I could design and manage multiple agents for different companies ?

Additionally, I would like to know if it is possible to connect these agents to French phone numbers (+33). I am also wondering about the availability of native French voices on your platform, as I did not clearly identify this option during my initial explorations.

To help me plan the scale of my projects, could you also tell me the limitations of the free version, particularly in terms of the number of daily API calls, concurrent calls, and additional development and integration capabilities ?

I’m also interested in the key differences between the various AI models offered (e.g., GPT-5.1, Claude, etc.), particularly regarding their features, performance, and the use cases for which they are best suited.

Finally, I’d like to learn more about the certified partnership you offer: what are the terms, benefits, and prerequisites ? I’d also like a clearer understanding of how billing works. Are agent usage minutes billed at the end of the month or in real time ? Is there a fee for setting up an agent, or is billing only applied when the agent is actually used ?

Thank you in advance for your response, and please let me know if you need any further clarification.

Best regards,

Gardais

Baptiste

baptiste.gardais@gmail.com

(+33)760113697

Hi @baptiste.gardais

Retell allows you to manage multiple client agents within a single account, with scalability mainly limited by your concurrency quota rather than the number of agents. While it natively supports US and other numbers, international numbers like French (+33) can be integrated using external providers such as Twilio or Telnyx. The platform supports French language and voices across major TTS providers, with voice selection influencing accent and delivery. Pricing follows a usage-based, per-minute billing model with no clear free tier specified, and additional costs may apply for higher token usage or faster processing tiers. Although various LLM configuration options are available, detailed model comparisons are not provided in the documentation. Retell also offers a tiered Partner Program with increasing benefits based on customer onboarding or content contributions.

Thank You