diff --git a/composer.json b/composer.json
index ca15f26..048c592 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
         "psr-4": { "League\\ISO3166\\": "src" }
     },
     "require-dev": {
-        "phpunit/phpunit": "^9.5"
+        "phpunit/phpunit": "^11.4"
     },
     "autoload-dev": {
         "psr-4": { "League\\ISO3166\\": "tests" }