diff --git a/composer.json b/composer.json
index 053673e5d..778193c61 100644
--- a/composer.json
+++ b/composer.json
@@ -22,6 +22,7 @@
     "require": {
         "php": ">=5.3",
         "ext-zlib": "*",
+        "ext-iconv": "*",
         "ext-mbstring": "*",
         "ext-pdo": "*"
     },