If a QuickBooks Online Admin removes an Accounting firm from their Manage Users list, the firm will receive an email letting them know their access has been removed.
Once you're ready to remove them, the steps below are sure to be of assistance:
Remove an Accountant User
From QuickBooks Online, click the Gear icon (⚙).
Select Manage Users.
Under Accounting firms, find the name of the accountant you wish to remove.
In the Action drop-down menu, select Delete (see below).
Click Delete to confirm your selection.
This information is also available from our guide on managing an accountant user for your convenience. Doing this will remove the accountant and their access to your Online company without a moment's delay. Please don't hesitate to keep in touch with me here should you need any additional assistance. Thanks for coming to the Community, wishing you and your business continued success in all that you do.