Notebooks for OneNote for the web are stored on OneDrive. If you no longer need a particular notebook, you can delete it. If there’s a chance that you’ll want to use it again later, you can keep the notebook and use the OneNote desktop app to change who can view or edit it.
Important: Before deleting a notebook that you’ve shared with others, let everyone who has permission to view or edit it know that you’re planning to remove the notebook, so they don’t lose their work. Deleting a notebook is permanent. After you delete it, you will not be able to recover it.
To delete a notebook, do the following:
Go to your OneDrive account and navigate to the notebook that you want to delete (it’s likely stored in Files > Documents).
Right-click the name of the notebook, and then select Delete.
I still see my notebook after deleting it
After you delete a notebook, it might still show up in your list of notebooks online. If you prefer a cleaner list of only the notebooks that you actively use, you can open the OneNote for desktop app and remove the deleted notebook from your list of notebooks.
Do the following:
Open the OneNote desktop app and go to your list of notebooks.
Right-click the notebook name, and then click Close this Notebook.