diff --git a/composer.json b/composer.json
index f8ebcbf15..ccf216c9a 100644
--- a/composer.json
+++ b/composer.json
@@ -14,7 +14,7 @@
     ],
     "minimum-stability": "dev",
     "require": {
-        "php": "^5.5 || ^7.0",
+        "php": "^5.6 || ^7.0",
         "ext-pdo": "*",
         "doctrine/collections": "~1.2",
         "doctrine/dbal": ">=2.5-dev,<2.7-dev",