Archiving
1
On the Home page, find the project and open its three-dot menu
Click Archive Project. The project disappears from the default view but keeps all of its comments, settings and history.

2
To see archived projects, use the filter button
Archived projects are hidden by default. Open the filter next to the search box and include archived projects to see them again.
3
To bring one back, choose Unarchive Project
The project returns to your active list exactly as it was.
Archived projects do not count as active projects for billing. See What is an Active Project.