While you can delete individual themes and copies of themes in the theme tab, the storefront host itself cannot not directly deleted. In lieu of deleting the storefront host, you can "Lock" the storefront host. A locked storefront host is not publicly browsable unless you share the access password with the person browsing there.

Locking a storefront removes the storefront host from your storefront count, so it effectively "deletes" it from affecting your service plan due to storefront host count.

Modifying the UltraCart main menu to show only the unlocked storefronts in the Storefronts pop out menu

Navigate to the "Your Preferences" page, then in the "Menu Navigation" section, left-mouse click the "Storefronts" menu item.
In the sub-menu that appears, click the "eye" icon for the storefront(s) you wish to hide from the menu.
After making your desired changes, click the "Save" button at the bottom of the page.

Example of modifications to the Navigation Menu to toggle the display and the ordering of the storefront hosts

Modify-Menu-Nav-Storefronts.mp4

Related Documentation

Delete a theme

Locking your Storefront Host

Your Preferences#MenuNavigation

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