diff --git a/.travis.yml b/.travis.yml
index b1ea204c..ee9faaf5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,7 +3,6 @@ language: php
 sudo: false
 
 php:
-    - 5.4
     - 5.5
     - 5.6
     - 7
diff --git a/README.md b/README.md
index 5e5e563f..3eca3bd7 100644
--- a/README.md
+++ b/README.md
@@ -23,8 +23,8 @@ The release process [is described here](doc/Release.md).
 
 ## Prerequisites
 
-This library needs at least `PHP 5.5.9`.
-It has been successfully tested using `PHP 5.5.9`, `PHP 5.6`, `PHP 7` and `HHVM`
+This library needs at least `PHP 5.5`.
+It has been successfully tested using `PHP 5.5`, `PHP 5.6`, `PHP 7` (stable and nightly branches) and `HHVM`
 
 ## Installation
 
diff --git a/composer.json b/composer.json
index 2f647a97..5d046eac 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,7 @@
         }
     ],
     "require": {
-        "php": ">=5.4",
+        "php": ">=5.5",
         "christian-riesen/base32": "^1.1",
         "beberlei/assert": "^2.0",
         "symfony/polyfill-mbstring": "^1.1",