diff --git a/composer.json b/composer.json
index c5b3fbd6..2642625b 100644
--- a/composer.json
+++ b/composer.json
@@ -44,7 +44,7 @@
         "fzaninotto/faker": "^1.5",
         "graham-campbell/testbench-core": "^1.1",
         "mockery/mockery": "0.9.4",
-        "phpunit/phpunit": "4.8.19"
+        "phpunit/phpunit": "4.8.21"
     },
     "autoload": {
         "classmap": [