As long as your subscription is canceled, no other action is necessary to close your account. It is possible to manually delete your data, if desired.
If you feel that Flow is no longer a good fit, you can cancel your subscription at any time in the Billing and Organization settings, found in the dropdown menu in the top left of Flow. In order for a cancellation to take place in time to stop a renewal, it must be submitted 3-5 days before your renewal date. If your account has any unpaid invoices, those will need to be paid before the cancellation can go through.
If you're using the Mac App Store version of the Flow app, you'll have to go to manage.getflow.com in a browser to make changes to your billing information or subscription.
Click "Manage Subscription" to go to your subscription page. Once there, click "Cancel Subscription" at the bottom of the page.
You will be brought to a confirmation page to finalize the cancellation. Click “Cancel” to Confirm. Once confirmed, you will see a yellow alert next to your subscription “You have canceled your [ ] plan”. Your account will close when your subscription period runs out, as indicated.
Note: Once your account is closed, your organization data will be deleted after 30 days.