You are able to cancel your Payment Subscription at any time, no strings attached! If you decide to reopen your site, you can start it back up whenever, with all of your data still present.
To completely cancel your account, you will need to cancel payments and delete the organization.
To cancel the payment, go to the Organizer Dashboard
In the top right corner, go to Payments, then under "Cancel Plan" click on Cancel
Confirm cancelation by clicking on OK.
To learn how to delete your organization's account next, read more about it here.