If an account is no longer active it is easy to keep track of this through the Inactive Account List on the accounts page.
First, go to the account you are wanting to deactivate.
Next to where you would delete the account you will see this icon: After clicking on the icon the following screen will appear:
Once you have deactivated the account you can see a full list of the deactivated accounts on the Accounts page by clicking “View Inactive Accounts” directly above the Total MRR.
If at some point the account becomes active again you can reactivate it by hovering to the right of the “Last Modified Date” column.