diff --git a/CHANGELOG.md b/CHANGELOG.md
index 50cbc1f8f..d12c70d83 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -58,6 +58,12 @@
     * Doctrine filecache is now namespaced with prefix to support purging
     * Register all page types into `blueprint://pages` stream
     
+# v1.5.4
+## mm/dd/2018
+
+1. [](#bugfix)
+    * Fixed fatal error if calling `$session->invalidate()` when there's no active session
+    
 # v1.5.3
 ## 10/08/2018
 
diff --git a/system/src/Grav/Framework/Session/Session.php b/system/src/Grav/Framework/Session/Session.php
index e66c211a9..077adb15a 100644
--- a/system/src/Grav/Framework/Session/Session.php
+++ b/system/src/Grav/Framework/Session/Session.php
@@ -225,8 +225,10 @@ class Session implements SessionInterface
             $params['httponly']
         );
 
-        session_unset();
-        session_destroy();
+        if ($this->isSessionStarted()) {
+            session_unset();
+            session_destroy();
+        }
 
         $this->started = false;