If the account is a customer account, no, they are free.
If you add them to any of the Jira "can log in" groups, so they can use Jira as well as the portal, then they do cost, as they're now a Jira user.
Hello Atlassian Community! I'm Tania, a Senior Product Marketing Manager for Jira Service Desk Cloud! I'm excited to announce some exciting improvements coming up for those who work with queues and...
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