# Reserve Site Names on the Network

> Blocks signups for site names you want to keep, such as shop, support or your brand names, on top of WordPress's built-in reserved list.

- Type: PHP
- Runs: Run everywhere
- Category: [Multisite](https://wpide.com/library/category/multisite/)
- Tags: signup, site-names, reserved
- Author: WPIDE Team
- Installs: 0
- Updated: 2026-10-28
- Page: https://wpide.com/library/ms-reserved-site-names/

## Code

```php
if ( ! is_multisite() ) {
    return;
}

$wpide_reserved = array( 'shop', 'store', 'support', 'help', 'admin', 'login', 'api', 'docs', 'status', 'billing' ); // Lower case.

add_filter( 'subdirectory_reserved_names', function ( $names ) use ( $wpide_reserved ) {
    return array_merge( $names, $wpide_reserved );
} );

add_filter( 'wpmu_validate_blog_signup', function ( $result ) use ( $wpide_reserved ) {
    if ( ! is_super_admin() && in_array( strtolower( (string) $result['blogname'] ), $wpide_reserved, true ) ) {
        $result['errors']->add( 'blogname', 'That site name is reserved. Please choose another one.' );
    }

    return $result;
} );
```

## Notes

Names are compared in lower case; add as many as you need.

## How to use it

Install the free WPIDE plugin (https://wordpress.org/plugins/wpide/), find "Reserve Site Names on the Network" in its snippet library and add it in one click; or create a new PHP snippet in WPIDE (or any code snippets plugin) and paste the code above. More snippets: https://wpide.com/library/