diff --git a/src/wp-includes/query.php b/src/wp-includes/query.php
index 592e70e0290a3..bf7af551781cf 100644
--- a/src/wp-includes/query.php
+++ b/src/wp-includes/query.php
@@ -1104,6 +1104,21 @@ function wp_old_slug_redirect() {
 			$link = user_trailingslashit( trailingslashit( $link ) . 'embed' );
 		}
 
+		$query_string = isset( $_SERVER['QUERY_STRING'] ) ? (string) $_SERVER['QUERY_STRING'] : '';
+
+		if ( '' !== $query_string ) {
+			$fragment = strstr( $link, '#' );
+
+			if ( false !== $fragment ) {
+				$link = substr( $link, 0, -strlen( $fragment ) );
+			} else {
+				$fragment = '';
+			}
+
+			$link .= false === strpos( $link, '?' ) ? '?' : '&';
+			$link .= $query_string . $fragment;
+		}
+
 		/**
 		 * Filters the old slug redirect URL.
 		 *
diff --git a/tests/phpunit/tests/rewrite/oldSlugRedirect.php b/tests/phpunit/tests/rewrite/oldSlugRedirect.php
index cf38ba452eabf..ddbf6497d032f 100644
--- a/tests/phpunit/tests/rewrite/oldSlugRedirect.php
+++ b/tests/phpunit/tests/rewrite/oldSlugRedirect.php
@@ -34,6 +34,7 @@ public function set_up() {
 
 	public function tear_down() {
 		$this->old_slug_redirect_url = null;
+		unset( $_SERVER['QUERY_STRING'] );
 
 		parent::tear_down();
 	}
@@ -55,6 +56,59 @@ public function test_old_slug_redirect() {
 		$this->assertSame( $permalink, $this->old_slug_redirect_url );
 	}
 
+	/**
+	 * @ticket 65267
+	 */
+	public function test_old_slug_redirect_preserves_query_string() {
+		$old_permalink = user_trailingslashit( get_permalink( self::$post_id ) );
+
+		wp_update_post(
+			array(
+				'ID'        => self::$post_id,
+				'post_name' => 'bar-baz',
+			)
+		);
+
+		$permalink    = user_trailingslashit( get_permalink( self::$post_id ) );
+		$query_string = 'utm_source=flyer&foo=a%2Bb&a=1&a=2';
+
+		$this->go_to( $old_permalink . '?' . $query_string );
+		$_SERVER['QUERY_STRING'] = $query_string;
+
+		wp_old_slug_redirect();
+		$this->assertSame( $permalink . '?' . $query_string, $this->old_slug_redirect_url );
+	}
+
+	/**
+	 * @ticket 65267
+	 */
+	public function test_old_slug_redirect_preserves_query_string_before_fragment() {
+		$old_permalink = user_trailingslashit( get_permalink( self::$post_id ) );
+
+		wp_update_post(
+			array(
+				'ID'        => self::$post_id,
+				'post_name' => 'bar-baz',
+			)
+		);
+
+		$permalink    = user_trailingslashit( get_permalink( self::$post_id ) ) . '?existing=1';
+		$query_string = 'utm_source=flyer';
+
+		add_filter(
+			'post_link',
+			static function ( $url ) {
+				return $url . '?existing=1#campaign-details';
+			}
+		);
+
+		$this->go_to( $old_permalink . '?' . $query_string );
+		$_SERVER['QUERY_STRING'] = $query_string;
+
+		wp_old_slug_redirect();
+		$this->assertSame( $permalink . '&' . $query_string . '#campaign-details', $this->old_slug_redirect_url );
+	}
+
 	/**
 	 * @ticket 36723
 	 */