There are many articles on the internet about how to use WordPress Multisite and its benefits, user support, capabilities to power several blogs from one installation. But you can find only few articles how to delete WordPress Multisite.
Deleting WordPress Multisite data was a new subject and many WordPress experts who have been using over years has no idea about this.
I am sharing how to remove WordPress Multisite data completely in case you don’t want it or you want to re-install in future with a fresh state or whatever.
Before proceeding to the steps make sure you take a backup of the database so you can restore it if something goes wrong. And if you don’t feel comfortable or don’t really know what you are doing, then you shouldn’t be doing it.
Remove all the code lines which you have added earlier for enabling Multisite on your wp-config.php file.
Revert back to your older .htaccess file or delete it and regenerate it by going to
Settings > Permalinks
Remove the two fields generated to the users table that are multisite only (deleted and spam columns).
Drop the following tables generated by WordPress in database at PhpMy Admin (prefixed by your DB prefix which is generally wp_):
wp_sitecategories (if you have global terms enabled)
Now you have a clean WordPress install without any traces of WordPress Multisite data.