You can add new users to your existing Burp Suite Professional license from your PortSwigger account. Find your subscription and click on the "Increase users" option from the Manage Subscription
dropdown box and follow the prompts to the payment screen. Please note the cost is calculated pro-rata based on the number of days remaining on the license.
Looking to add users via a reseller? Provide your reseller with either the previous PortSwigger Order Number or the Email address of the End-User currently associated with the subscription and how
many users you would like to add so they can contact us for a quotation.