Yes and No. By default, a user can submit a ticket without an account, but you can change this to require the user to create an account in order to do so.
Why would I want my users to have accounts to submit a ticket?
Since all, we require from the user is an email address to submit a ticket when they do not already have an account with SeamlessDesk the only information we can obtain from that user is their email address and maybe their name. If you require a user to create an account then you can gather more information from that user to help you better communicate with them.
How do I change the setting to require users to have an account to submit a ticket?
1. Go to Site Setting > Settings
2. Click on "Tickets"
3. Change the default value on "Allow users to submit a ticket through your portal without being logged into the site?" from Yes to No