diff --git a/src/wp-includes/class-wpdb.php b/src/wp-includes/class-wpdb.php
index 869111efd0797..dcac704007cba 100644
--- a/src/wp-includes/class-wpdb.php
+++ b/src/wp-includes/class-wpdb.php
@@ -1957,7 +1957,8 @@ public function flush() {
 	 * If `$allow_bail` is false, the lack of database connection will need to be handled manually.
 	 *
 	 * @since 3.0.0
-	 * @since 3.9.0 $allow_bail parameter added.
+	 * @since 3.9.0 Added `$allow_bail` parameter.
+	 * @since 7.2.0 Added status and no-cache headers before loading a custom `db-error.php` drop-in.
 	 *
 	 * @param bool $allow_bail Optional. Allows the function to bail. Default true.
 	 * @return bool True with a successful connection, false on failure.
@@ -2009,8 +2010,13 @@ public function db_connect( $allow_bail = true ) {
 		if ( ! $this->dbh && $allow_bail ) {
 			wp_load_translations_early();
 
-			// Load custom DB error template, if present.
+			/*
+			 * Load custom DB error template, if present.
+			 * A 500 status header and no-cache headers are now sent before loading a custom db-error.php drop-in.
+			 */
 			if ( file_exists( WP_CONTENT_DIR . '/db-error.php' ) ) {
+				status_header( 500 );
+				nocache_headers();
 				require_once WP_CONTENT_DIR . '/db-error.php';
 				die();
 			}
diff --git a/src/wp-includes/functions.php b/src/wp-includes/functions.php
index 4c323812991d7..f3d74749a150c 100644
--- a/src/wp-includes/functions.php
+++ b/src/wp-includes/functions.php
@@ -5634,6 +5634,7 @@ function wp_ob_end_flush_all() {
  * in WordPress 2.5.0.
  *
  * @since 2.3.2
+ * @since 7.2.0 Added status and no-cache headers before loading a custom `db-error.php` drop-in.
  *
  * @global wpdb $wpdb WordPress database abstraction object.
  *
@@ -5646,6 +5647,8 @@ function dead_db() {
 
 	// Load custom DB error template, if present.
 	if ( file_exists( WP_CONTENT_DIR . '/db-error.php' ) ) {
+		status_header( 500 );
+		nocache_headers();
 		require_once WP_CONTENT_DIR . '/db-error.php';
 		die();
 	}
diff --git a/src/wp-includes/load.php b/src/wp-includes/load.php
index 9d407453424c5..71dc7d47df44e 100644
--- a/src/wp-includes/load.php
+++ b/src/wp-includes/load.php
@@ -395,6 +395,7 @@ function wp_favicon_request() {
  * the wp-content directory).
  *
  * @since 3.0.0
+ * @since 7.2.0 Added status and no-cache headers before loading a custom `maintenance.php` drop-in.
  * @access private
  */
 function wp_maintenance() {
@@ -403,12 +404,16 @@ function wp_maintenance() {
 		return;
 	}
 
+	require_once ABSPATH . WPINC . '/functions.php';
+
 	if ( file_exists( WP_CONTENT_DIR . '/maintenance.php' ) ) {
+		status_header( 503 );
+		nocache_headers();
+		header( 'Retry-After: 600' );
 		require_once WP_CONTENT_DIR . '/maintenance.php';
 		die();
 	}
 
-	require_once ABSPATH . WPINC . '/functions.php';
 	wp_load_translations_early();
 
 	header( 'Retry-After: 600' );