How to change a Squarespace url slug
How do I change the URL slug for a page in Squarespace?
To change a page's URL slug in Squarespace:
Open the page settings by clicking the gear icon next to the page name.
Under the "General" tab, edit the "URL Slug" field.
Click "Save" and your new URL will be live.
IMPORTANT
If the old page slug had already been indexed by Google you will need to set up a URL mapping so that people trying to access the old slug are directed to the new one.
This is good for user experience and also tells Google to preserve SEO power.