diff --git a/composer.json b/composer.json
index 35dce0c530837ffc339cef00454002a815e7971d..61770642bec1bab2dac973a747b9752a21971b38 100644
--- a/composer.json
+++ b/composer.json
@@ -20,11 +20,11 @@
     },
     "config":{
         "platform": {
-            "php": "5.5.0"
+            "php": "5.5.9"
         }
     },
     "require": {
-        "php": ">=5.5.0",
+        "php": ">=5.5.9",
         "twig/twig": "~1.0",
         "leafo/lessphp": "~0.5.0",
         "symfony/console": "~2.6.0",
diff --git a/core/testMinimumPhpVersion.php b/core/testMinimumPhpVersion.php
index a63453ea85db1388edbc3008e6e3f4e9d19835a0..adc4b487db99c694e919d2453d59e3d8da3507f0 100644
--- a/core/testMinimumPhpVersion.php
+++ b/core/testMinimumPhpVersion.php
@@ -19,7 +19,7 @@ $piwik_errorMessage = '';
 // NOTE: when changing this variable, we also need to update
 // 1) api.piwik.org
 // 2) tests/travis/generator/Generator.php
-$piwik_minimumPHPVersion = '5.5.0';
+$piwik_minimumPHPVersion = '5.5.9';
 $piwik_currentPHPVersion = PHP_VERSION;
 $minimumPhpInvalid = version_compare($piwik_minimumPHPVersion, $piwik_currentPHPVersion) > 0;
 if ($minimumPhpInvalid) {
diff --git a/tests/PHPUnit/Integration/ReleaseCheckListTest.php b/tests/PHPUnit/Integration/ReleaseCheckListTest.php
index 41e46b0cc68ab9952b867e3dc5eb5061b648cf0d..8357826275b0b6c60dbe352ecc73aab8ae090d2e 100644
--- a/tests/PHPUnit/Integration/ReleaseCheckListTest.php
+++ b/tests/PHPUnit/Integration/ReleaseCheckListTest.php
@@ -28,7 +28,7 @@ class ReleaseCheckListTest extends \PHPUnit_Framework_TestCase
 {
     private $globalConfig;
 
-    const MINIMUM_PHP_VERSION = '5.5.0';
+    const MINIMUM_PHP_VERSION = '5.5.9';
 
     public function setUp()
     {