diff --git a/plugins/bcc-login/includes/class-bcc-login-settings.php b/plugins/bcc-login/includes/class-bcc-login-settings.php
index fc175f2..b38e599 100644
--- a/plugins/bcc-login/includes/class-bcc-login-settings.php
+++ b/plugins/bcc-login/includes/class-bcc-login-settings.php
@@ -657,6 +657,11 @@ function render_delete_subscribers_button () {
             <h2><?php _e( 'Maintenance', 'bcc-login' ); ?></h2>		
             <p><?php _e( 'We recommend deleting subscribers that were automatically generated by earlier versions of the login plugin.', 'bcc-login') ?></p>
             <p><?php _e( 'This also removes the tokens and login data stored by earlier versions for all users, and expired transients.', 'bcc-login') ?></p>
+            <?php if ( is_multisite() && $this->_settings->create_missing_users ) : ?>
+                <p><?php _e( 'On a network, subscribers who also belong to another site are kept: with OIDC_CREATE_USERS on, they couldn\'t log in here again after only leaving this site. Network administrators are left alone. Only a network administrator can delete user accounts.', 'bcc-login' ) ?></p>
+            <?php elseif ( is_multisite() ) : ?>
+                <p><?php _e( 'On a network, subscribers who also belong to another site only leave this site, and network administrators are left alone. Only a network administrator can delete user accounts.', 'bcc-login' ) ?></p>
+            <?php endif; ?>
             <form method="post">
 				<?php wp_nonce_field( 'delete_subscribers', 'delete_subscribers_nonce' ); ?>
 				<?php submit_button('Delete subscribers', 'delete', 'delete_subscribers', false, array(
@@ -680,25 +685,46 @@ function delete_subscribers_handler() {
         ) {
             global $wpdb;
 
-            // Remember who gets deleted, to remove them from the object cache afterwards. The cleanup below only
-            // finds users that still have meta left, which isn't the case if the role was their only meta.
-            $subscriber_ids = array_map( 'intval', $wpdb->get_col(
-                "SELECT user_id FROM {$wpdb->prefix}usermeta
-                WHERE meta_key = '{$wpdb->prefix}capabilities' AND meta_value LIKE 'a:1:{s:10:\"subscriber\";b:1;}'"
-            ) );
+            // Users whose only role on this site is subscriber. On a network the users and usermeta tables are
+            // shared by all sites, and the role is in this site's capabilities meta.
+            $capabilities_key = $wpdb->get_blog_prefix() . 'capabilities';
+            $subscriber_ids = array_map( 'intval', $wpdb->get_col( $wpdb->prepare(
+                "SELECT user_id FROM {$wpdb->usermeta} WHERE meta_key = %s AND meta_value = %s",
+                $capabilities_key,
+                'a:1:{s:10:"subscriber";b:1;}'
+            ) ) );
+
+            // Of those, the ones who also belong to another site of the network. Null when a query failed.
+            $member_ids = '' === $wpdb->last_error ? array() : null;
+            if ( is_multisite() && null !== $member_ids ) {
+                // Network administrators are left alone, whatever their role on this site.
+                $subscriber_ids = array_values( array_diff( $subscriber_ids, $this->get_network_admin_ids() ) );
+                $member_ids = $this->get_other_sites_member_ids( $subscriber_ids, $capabilities_key );
+            }
 
-            $sql = "DELETE {$wpdb->prefix}users, {$wpdb->prefix}usermeta
-                    FROM {$wpdb->prefix}users
-                    INNER JOIN {$wpdb->prefix}usermeta ON {$wpdb->prefix}users.ID = {$wpdb->prefix}usermeta.user_id
-                    WHERE
-                        meta_key = '{$wpdb->prefix}capabilities' AND
-                        meta_value LIKE 'a:1:{s:10:\"subscriber\";b:1;}'";
+            // On a network, subscribers who also belong to another site keep their account and only leave this
+            // site, and only network administrators may delete accounts. With OIDC_CREATE_USERS on, the login
+            // can't add an existing account back to a site, so nobody only leaves: they're kept until they can
+            // be deleted.
+            $can_delete = ! is_multisite() || current_user_can( 'delete_users' );
+            $deleted_ids = array();
+            $removed_ids = array();
+            if ( null !== $member_ids ) {
+                $deleted_ids = $can_delete ? array_values( array_diff( $subscriber_ids, $member_ids ) ) : array();
+                $removed_ids = $this->_settings->create_missing_users ? array() : array_values( array_diff( $subscriber_ids, $deleted_ids ) );
+            }
+            $kept_ids = array_values( array_diff( $subscriber_ids, $deleted_ids, $removed_ids ) );
 
-            $subscribers_deleted = $wpdb->query($sql);
+            // Their logins, email addresses and slugs, to clear them from the object cache afterwards.
+            $cached_users = $this->get_cache_keys_of_users( array_merge( $deleted_ids, $removed_ids ) );
 
-            BCC_Login_Cleanup::clean_deleted_users_cache( $subscriber_ids );
+            // Accounts first: if that fails, they're still subscribers, so deleting them again finds them.
+            // Nothing changes when the users couldn't be looked up.
+            $subscribers_deleted = null !== $member_ids && $this->delete_users( $deleted_ids ) && $this->remove_users_from_site( $removed_ids );
 
-            if ( false === $subscribers_deleted ) {
+            $this->clean_users_cache( $cached_users );
+
+            if ( ! $subscribers_deleted ) {
                 add_settings_error(
                     'subscribers_deleted',
                     'subscribers_not_deleted',
@@ -707,8 +733,8 @@ function delete_subscribers_handler() {
                 );
             }
 
-            // The join above only removes the capabilities meta row of each subscriber,
-            // so remove all remaining meta (e.g. openid-connect-generic-*) of users that no longer exist.
+            // Deleting an account above leaves its meta, so remove all meta (e.g. openid-connect-generic-*)
+            // of users that no longer exist.
             $orphaned_meta_deleted = BCC_Login_Cleanup::delete_orphaned_user_meta();
 
             if ( false === $orphaned_meta_deleted ) {
@@ -749,8 +775,44 @@ function delete_subscribers_handler() {
             // Only report the steps that succeeded, the others have an error notice.
             $messages = array();
 
-            if ( false !== $subscribers_deleted ) {
-                $messages[] = __( 'All subscribers were successfully deleted.' );
+            if ( $subscribers_deleted ) {
+                if ( ! is_multisite() ) {
+                    $messages[] = __( 'All subscribers were successfully deleted.' );
+                } else {
+                    if ( $can_delete ) {
+                        $messages[] = sprintf( _n( 'Deleted %d subscriber.', 'Deleted %d subscribers.', count( $deleted_ids ), 'bcc-login' ), count( $deleted_ids ) );
+                    }
+
+                    if ( $removed_ids ) {
+                        $messages[] = $can_delete
+                            ? sprintf(
+                                _n(
+                                    '%d subscriber belongs to another site of the network, so they were only removed from this site.',
+                                    '%d subscribers belong to another site of the network, so they were only removed from this site.',
+                                    count( $removed_ids ),
+                                    'bcc-login'
+                                ),
+                                count( $removed_ids )
+                            )
+                            : sprintf( _n( 'Removed %d subscriber from this site.', 'Removed %d subscribers from this site.', count( $removed_ids ), 'bcc-login' ), count( $removed_ids ) );
+                    }
+
+                    if ( $kept_ids ) {
+                        $messages[] = sprintf(
+                            _n(
+                                '%d subscriber was kept: with OIDC_CREATE_USERS on, they couldn\'t log in here again after only leaving this site.',
+                                '%d subscribers were kept: with OIDC_CREATE_USERS on, they couldn\'t log in here again after only leaving this site.',
+                                count( $kept_ids ),
+                                'bcc-login'
+                            ),
+                            count( $kept_ids )
+                        );
+                    }
+
+                    if ( ! $can_delete ) {
+                        $messages[] = __( 'Only a network administrator can delete user accounts.', 'bcc-login' );
+                    }
+                }
             }
 
             if ( false !== $orphaned_meta_deleted ) {
@@ -773,6 +835,134 @@ function delete_subscribers_handler() {
         }
     }
 
+    /**
+     * The user ids of the network administrators.
+     */
+    private function get_network_admin_ids() {
+        $ids = array();
+
+        foreach ( get_super_admins() as $login ) {
+            $user = get_user_by( 'login', $login );
+            if ( $user ) {
+                $ids[] = $user->ID;
+            }
+        }
+
+        return $ids;
+    }
+
+    /**
+     * Of the given users, those who belong to another site of the network: they have its capabilities meta,
+     * with or without a role. Null when a query failed.
+     */
+    private function get_other_sites_member_ids( $user_ids, $capabilities_key ) {
+        global $wpdb;
+
+        $member_ids = array();
+        $any_site_capabilities = '/^' . preg_quote( $wpdb->base_prefix, '/' ) . '(\d+_)?capabilities$/';
+
+        foreach ( array_chunk( $user_ids, 1000 ) as $chunk ) {
+            $rows = $wpdb->get_results( $wpdb->prepare(
+                "SELECT user_id, meta_key FROM {$wpdb->usermeta}
+                WHERE user_id IN (" . implode( ',', $chunk ) . ") AND meta_key LIKE %s AND meta_key != %s",
+                $wpdb->esc_like( $wpdb->base_prefix ) . '%capabilities',
+                $capabilities_key
+            ) );
+
+            if ( '' !== $wpdb->last_error ) {
+                return null;
+            }
+
+            foreach ( $rows as $row ) {
+                if ( preg_match( $any_site_capabilities, $row->meta_key ) ) {
+                    $member_ids[] = (int) $row->user_id;
+                }
+            }
+        }
+
+        return array_values( array_intersect( $user_ids, $member_ids ) );
+    }
+
+    /**
+     * The ids, logins, slugs and email addresses of the given users, which the object cache keys users by.
+     */
+    private function get_cache_keys_of_users( $user_ids ) {
+        global $wpdb;
+
+        $users = array();
+
+        foreach ( array_chunk( $user_ids, 1000 ) as $chunk ) {
+            $users = array_merge( $users, $wpdb->get_results(
+                "SELECT ID, user_login, user_nicename, user_email FROM {$wpdb->users} WHERE ID IN (" . implode( ',', $chunk ) . ')'
+            ) );
+        }
+
+        return $users;
+    }
+
+    /**
+     * Removes the given users from the object cache, as clean_user_cache() does for one user, which would
+     * load each user and their meta first.
+     */
+    private function clean_users_cache( $users ) {
+        foreach ( $users as $user ) {
+            wp_cache_delete( $user->ID, 'users' );
+            wp_cache_delete( $user->ID, 'user_meta' );
+            wp_cache_delete( $user->user_login, 'userlogins' );
+            wp_cache_delete( $user->user_nicename, 'userslugs' );
+
+            if ( ! empty( $user->user_email ) ) {
+                wp_cache_delete( $user->user_email, 'useremail' );
+            }
+        }
+
+        // Cached user queries, e.g. the users list (WordPress 6.3+).
+        if ( $users && function_exists( 'wp_cache_set_users_last_changed' ) ) {
+            wp_cache_set_users_last_changed();
+        }
+    }
+
+    /**
+     * Deletes the accounts of the given users, in bulk: there can be thousands, too many for wp_delete_user()
+     * or wpmu_delete_user(), which would also delete any posts they wrote. So their posts are kept, and
+     * WordPress's user deletion hooks don't run (nothing in BCC's plugins uses them). Their meta is removed
+     * afterwards, with the meta of all users that no longer exist.
+     */
+    private function delete_users( $user_ids ) {
+        global $wpdb;
+
+        foreach ( array_chunk( $user_ids, 1000 ) as $chunk ) {
+            if ( false === $wpdb->query( "DELETE FROM {$wpdb->users} WHERE ID IN (" . implode( ',', $chunk ) . ')' ) ) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Removes the given users from this site, as WordPress does: their role and user level on the site.
+     */
+    private function remove_users_from_site( $user_ids ) {
+        global $wpdb;
+
+        $blog_prefix = $wpdb->get_blog_prefix();
+
+        foreach ( array_chunk( $user_ids, 1000 ) as $chunk ) {
+            $removed = $wpdb->query( $wpdb->prepare(
+                "DELETE FROM {$wpdb->usermeta} WHERE meta_key IN (%s, %s) AND user_id IN (" . implode( ',', $chunk ) . ')',
+                $blog_prefix . 'capabilities',
+                $blog_prefix . 'user_level'
+            ) );
+
+            if ( false === $removed ) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
     function render_group_selector_field( $args ) { ?>
         <div id="<?php echo $args['groupsName']; ?>-container"></div>
         <script type="text/javascript">