diff --git a/CHANGELOG.md b/CHANGELOG.md
index b8afd1156..207fce76a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,7 @@
 ## mm/dd/2018
 
 1. [](#new)
-    * Set minimum requirements to [PHP 5.6.0](https://getgrav.org/blog/raising-php-requirements-2018)
+    * Set minimum requirements to [PHP 5.6.4](https://getgrav.org/blog/raising-php-requirements-2018)
     * Updated Doctrine Collections to 1.4
     * Updated Symfony Components to 3.4, causing some compatibility issues with YAML files
 
diff --git a/README.md b/README.md
index 9f4fc1216..5afbe4365 100644
--- a/README.md
+++ b/README.md
@@ -18,7 +18,7 @@ The underlying architecture of Grav is designed to use well-established and _bes
 
 # Requirements
 
-- PHP 5.6.0 or higher. Check the [required modules list](https://learn.getgrav.org/basics/requirements#php-requirements)
+- PHP 5.6.4 or higher. Check the [required modules list](https://learn.getgrav.org/basics/requirements#php-requirements)
 - Check the [Apache](https://learn.getgrav.org/basics/requirements#apache-requirements) or [IIS](https://learn.getgrav.org/basics/requirements#iis-requirements) requirements
 
 # QuickStart
diff --git a/composer.json b/composer.json
index ef53dd67e..890caec84 100644
--- a/composer.json
+++ b/composer.json
@@ -6,7 +6,7 @@
     "homepage": "http://getgrav.org",
     "license": "MIT",
     "require": {
-        "php": ">=5.6.0",
+        "php": ">=5.6.4",
         "twig/twig": "~1.24",
         "erusev/parsedown": "1.6.4",
         "erusev/parsedown-extra": "~0.7",
@@ -45,7 +45,7 @@
     },
     "config": {
         "platform": {
-            "php": "5.6.0"
+            "php": "5.6.4"
         }
     },
     "repositories": [
diff --git a/composer.lock b/composer.lock
index f0c2b347e..0b6605664 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "5800ff038fd33c170deb63581af9f206",
+    "content-hash": "e3d08425a81cf7c482391f4580b52cd5",
     "packages": [
         {
             "name": "antoligy/dom-string-iterators",
@@ -3628,7 +3628,7 @@
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
-        "php": ">=5.6.0",
+        "php": ">=5.6.4",
         "ext-mbstring": "*",
         "ext-openssl": "*",
         "ext-curl": "*",
@@ -3636,6 +3636,6 @@
     },
     "platform-dev": [],
     "platform-overrides": {
-        "php": "5.6.0"
+        "php": "5.6.4"
     }
 }
diff --git a/index.php b/index.php
index 0a2008055..96ca67a1a 100644
--- a/index.php
+++ b/index.php
@@ -7,7 +7,7 @@
  */
 
 namespace Grav;
-define('GRAV_PHP_MIN', '5.6.0');
+define('GRAV_PHP_MIN', '5.6.4');
 
 // Ensure vendor libraries exist
 $autoload = __DIR__ . '/vendor/autoload.php';
diff --git a/system/defines.php b/system/defines.php
index 2a8e2dacc..fe02c9e72 100644
--- a/system/defines.php
+++ b/system/defines.php
@@ -13,7 +13,7 @@ define('GRAV_TESTING', false);
 define('DS', '/');
 
 if (!defined('GRAV_PHP_MIN')) {
-    define('GRAV_PHP_MIN', '5.6.0');
+    define('GRAV_PHP_MIN', '5.6.4');
 }
 
 // Directories and Paths