Theoretically, infinite.
We are a cloud provider and so, we tend to have a lot of spare capacity to handle spikes, But please intimate us if you will receive more than 20 concurrent phone calls. We would then just double-check that we have enough spare capacity available to take these calls.
As a general principle, please intimate support before you undertake an advertisement on Radio, TV or Newspaper.
If you have any questions or concerns, please connect with us using the chat widget on your Exotel Dashboard or Whatsapp us on 08088919888