“The Slug Is Not Unique” Error Explained

When saving pages in the CMS — especially brand new pages — you may occasionally see the error message:

“The slug is not unique.”

This error simply means that the page URL is duplicated and therefore cannot be saved. Every page on a website must have its own unique URL, and the CMS prevents duplicates to avoid conflicts.

What Is a Slug?

A slug is the last part of a page’s URL that identifies that specific page.

Example

If your page URL is:

https://www.example.com/about-us

The slug is:

about-us

Slugs are usually generated automatically from the page title and:

• Must be unique

• Cannot contain special characters

• Are used to create readable, SEO-friendly URLs

Why Does This Error Happen?

The most common reasons for this error are:

• The page URL was not generated properly when creating a new page

• Another page already exists with the same slug

• The page title produces a duplicate URL

• Special characters prevent the slug from being created

This is most commonly seen when building new pages.

Quick Fix (Most Common Solution)

In most cases, the fix is simple:

1. Click Save again on the page

2. The CMS will automatically generate a new, unique slug

3. The page should then save successfully

This resolves the issue in the majority of scenarios.

Manually Updating the Slug (If Needed)

If the error persists:

1. Open the page you are editing

2. Go to Page Options

3. Locate the Page URL field

4. Unlock the padlock

5. Enter a unique URL slug manually

6. Save the page again

The CMS will notify you if the slug is still in use.

Best Practice Tips

• Keep URLs short and descriptive

• Avoid special characters (e.g. £, %, &, ?)

• Use hyphens instead of spaces

• Ensure page titles are unique where possible

Summary

• A slug is the unique part of a page’s URL

• The error occurs when the slug already exists

• Re-saving the page usually fixes the issue

• URLs must be unique to allow pages to save correctly

If you continue to experience issues after trying the above steps, please contact the Support team and we’ll be happy to help.