diff --git a/create-cardholders-and-cards/server/php/composer.json b/create-cardholders-and-cards/server/php/composer.json
index 532d268..8aac4bc 100644
--- a/create-cardholders-and-cards/server/php/composer.json
+++ b/create-cardholders-and-cards/server/php/composer.json
@@ -1,6 +1,6 @@
 {
   "require": {
-    "stripe/stripe-php": "^15.0",
+    "stripe/stripe-php": "^16.6",
     "vlucas/phpdotenv": "^5.3"
   },
   "scripts": {