diff --git a/CHANGELOG.md b/CHANGELOG.md
index 97d58097..ddbb7c78 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 
 ### Changed
 
+- Block installations on unsupported higher PHP versions (#691)
+
 ### Deprecated
 
 ### Removed
diff --git a/composer.json b/composer.json
index cf15a944..049ff127 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
         }
     ],
     "require": {
-        "php": ">=5.6.20",
+        "php": "^5.6.20 || ^7.0.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0",
         "ext-iconv": "*"
     },
     "require-dev": {