A license is required for large Zoom conferences with more than 300 participants.
A separate license request must be submitted each time, unless it is for a recurring event such as a large class. Please allow up to 2 business days to fulfill requests.
Find which license you need with the Meeting vs Webinar Comparison.
Use the Request Large Webinar or Large Meeting button on the right to request the license.
See Zoom Webinar Help for more information