diff --git a/types/express-session/express-session-tests.ts b/types/express-session/express-session-tests.ts
index dc57e88f0d..9189db1dfb 100644
--- a/types/express-session/express-session-tests.ts
+++ b/types/express-session/express-session-tests.ts
@@ -11,7 +11,7 @@ app.use(session({
   secret: 'keyboard cat',
   name: 'connect.sid',
   store: new session.MemoryStore(),
-  cookie: { path: '/', httpOnly: true, secure: false },
+  cookie: { path: '/', httpOnly: true, secure: false, sameSite: true },
   genid: (req: express.Request): string => '',
   rolling: false,
   resave: true,
diff --git a/types/express-session/index.d.ts b/types/express-session/index.d.ts
index 29d2b4fbbc..fdceafeeea 100644
--- a/types/express-session/index.d.ts
+++ b/types/express-session/index.d.ts
@@ -32,6 +32,7 @@ declare global {
       httpOnly: boolean;
       domain?: string;
       expires: Date | boolean;
+      sameSite?: boolean | string;
     }
 
     interface SessionCookie extends SessionCookieData {