### Answer To handle 500 concurrent calls, you'd need to increase your concurrency limit from the default. Pay-As-You-Go workspaces are allocated a quota of 20 concurrent calls by default. [(1) ]() Your burst limit would be calculated as the lower of: - 3× your concurrency limit, OR - Your concurrency limit + 300 For a 500 concurrent call limit, your burst would allow up to 800 concurrent calls (500 + 300 = 800, which is less than 3 × 500 = 1500) . If concurrency burst is enabled and you exceed your standard 500 limit but stay within the 800 burst limit, those burst calls will have an additional $0.10/min surcharge applied to the entire call duration. To adjust your concurrency limit to 500, you can do so from the Settings > Limits page in your dashboard. For volumes over $3k/month, you may want to explore the Enterprise Plan for volume-based discounts and custom call concurrency. [(2) ]()

​ To learn more, see the sources I considered: [[1] Understand concurrency & limits](https://docs.retellai.com/deploy/concurrency) [[2] Inside Retell AI | The Conversational AI Platform Behind Scalable AI Phone Systems | Retell AI](https://www.retellai.com/blog/inside-retell-ai-conversational-ai-phone-system) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.

### Answer For 200 concurrent calls, you can adjust your concurrency limit from the dashboard at Settings > Limits. [(1) ]() With a 200 concurrent call limit, your burst capacity would allow up to 500 concurrent calls (200 + 300 = 500, which is less than 3 × 200 = 600) . If concurrency burst is enabled: - Calls within your standard 200 limit proceed with no additional charges - Calls that exceed 200 but stay within the 500 burst limit will have an additional $0.10/min surcharge applied to the entire call duration The burst surcharge applies to the entire duration of any call that started while in burst mode, not just the portion of time spent above the normal limit. You can enable or disable concurrency burst from the Settings > Limits page in your dashboard. Adjusting concurrency limits is available to the Admin and Developer roles.

​ To learn more, see the sources I considered: [[1] Understand concurrency & limits](https://docs.retellai.com/deploy/concurrency) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.