diff --git a/src/wp-includes/class-wpdb.php b/src/wp-includes/class-wpdb.php
index 869111efd0797..36f8e57278125 100644
--- a/src/wp-includes/class-wpdb.php
+++ b/src/wp-includes/class-wpdb.php
@@ -1958,6 +1958,7 @@ public function flush() {
 	 *
 	 * @since 3.0.0
 	 * @since 3.9.0 $allow_bail parameter added.
+	 * @since 7.2.0 A 500 status header and no-cache headers are now sent 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 4f5916a322620..f4a5093a277b5 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 A 500 status header and no-cache headers are now sent 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..3782d1e7ac6a2 100644
--- a/src/wp-includes/load.php
+++ b/src/wp-includes/load.php
@@ -395,6 +395,8 @@ function wp_favicon_request() {
  * the wp-content directory).
  *
  * @since 3.0.0
+ * @since 7.2.0 A 503 status header and no-cache headers are now sent before loading maintenance.php drop-in.
+ *              to ensure that the correct headers are sent.
  * @access private
  */
 function wp_maintenance() {
@@ -404,6 +406,9 @@ function wp_maintenance() {
 	}
 
 	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();
 	}