I managed to remove the slug “blog” from the main site of my WordPress Multisite.

Now, why would I want that? Simply because my URL is: blog.dys.ph. It it sure looks not ok to have: blog.dys.ph/blog/post-name, right? So I removed it.

Here’s how:

1. In your main site (the one with the “blog” slug), go to Settings > Permalinks (/wp-admin/options-permalink.php)
2. Choose “Default” and Save Changes
3. In your Network Admin Sites (/wp-admin/network/sites.php), edit the main site
4. On the Edit Site page, go to Settings (/wp-admin/network/site-settings.php?id=1)
5. Scroll to Permalinks section and populate the field with this value “/%postname%” (without the quotation marks) and Save Changes
6. Go to the URL of your main site and try it out – the “blog” slug should be gone