diff --git a/src/Http/IResponse.php b/src/Http/IResponse.php
index 800e1c8e..94b75d38 100644
--- a/src/Http/IResponse.php
+++ b/src/Http/IResponse.php
@@ -402,6 +402,7 @@ function setCookie(
 		?string $domain = null,
 		?bool $secure = null,
 		?bool $httpOnly = null,
+		?string $sameSite = null,
 	);
 
 	/**