How to Change a Custom Post Type Slug via a Child Theme

Sometimes, you may want to change the URL slug of a custom post type to better reflect your site’s content or improve SEO. If the custom post type is registered by a plugin or the parent theme, you can easily override the slug by adding a function in your child theme.

In this tutorial, we’ll walk you through the steps to change the slug of a custom post type when you already know the existing slug.

Step 1: Determine the Current Slug

Before making any changes, ensure you know the current slug of the custom post type. This slug is part of the URL when you view a post of that type. For example, if the current URL is https://yourdomain.com/old-slug/post-name/, then old-slug is the slug you want to change. Or you can check it in your WP Dashboard by hovering over the post type menu.

Step 2: Add the Function to Your Child Theme

To change the slug, you’ll need to add a function to your child theme’s functions.php file. This function will use WordPress hooks to modify the existing custom post type’s rewrite rules.

1. Open the functions.php file in your child theme. If you don’t have a functions.php file in your child theme, create one in your child theme directory.
2. Add the following function to modify the post type slug:

   function change_post_type_slug() {
       // Get the global WordPress variable for post types
       global $wp_post_types;
       
       // Check if the post type exists before trying to modify it
       if (isset($wp_post_types['your_post_type_slug'])) {
           // Get the post type object
           $post_type = $wp_post_types['your_post_type_slug'];
           
           // Modify the slug
           $post_type->rewrite['slug'] = 'new-slug';
           
           // Ensure the rewrite rules are applied correctly
           add_action('init', 'flush_rewrite_rules', 20);
       }
   }
   add_action('init', 'change_post_type_slug', 20);
   

    

   Replace 'your_post_type_slug' with the actual slug of the post type you want to change and 'new-slug' with the new slug you want to use.

3. Save the functions.php file after adding the function.

Step 3: Flush Rewrite Rules

To ensure the new slug is applied, you need to flush the rewrite rules in WordPress.

1. Go to Permalinks Settings: In your WordPress dashboard, navigate to Settings > Permalinks.
2. Save Changes: Scroll down and click the Save Changes button. You don’t need to change any settings; just saving will flush the rewrite rules.

Step 4: Verify the New Slug

Now, you can check to ensure the slug has been updated successfully.

1. View a Post: Navigate to a post of the custom post type you modified.
2. Check the URL: The URL should now reflect the new slug, e.g., https://yourdomain.com/new-slug/post-name/.

With just a few lines of code added to your child theme, you can easily change the slug of any custom post type, whether it’s part of a plugin or the parent theme. This method ensures your customizations persist even when the parent theme or plugin is updated.