diff --git a/src/Configuration/Defaults/CommonRules.php b/src/Configuration/Defaults/CommonRules.php
index 8ce9c01..21e9f49 100644
--- a/src/Configuration/Defaults/CommonRules.php
+++ b/src/Configuration/Defaults/CommonRules.php
@@ -14,6 +14,7 @@
 use PhpCsFixer\Fixer\Basic\NoMultipleStatementsPerLineFixer;
 use PhpCsFixer\Fixer\Basic\NoTrailingCommaInSinglelineFixer;
 use PhpCsFixer\Fixer\Basic\PsrAutoloadingFixer;
+use PhpCsFixer\Fixer\Casing\LowercaseKeywordsFixer;
 use PhpCsFixer\Fixer\Casing\LowercaseStaticReferenceFixer;
 use PhpCsFixer\Fixer\Casing\MagicConstantCasingFixer;
 use PhpCsFixer\Fixer\Casing\MagicMethodCasingFixer;
@@ -328,5 +329,6 @@ class CommonRules extends Rules
         CurlyBracesPositionFixer::class => [
             "anonymous_functions_opening_brace" => "same_line",
         ],
+        LowercaseKeywordsFixer::class => true,
     ];
 }
diff --git a/tests/codestyle/CommonRulesetTest.php b/tests/codestyle/CommonRulesetTest.php
index 2b97ea2..d7fc94d 100644
--- a/tests/codestyle/CommonRulesetTest.php
+++ b/tests/codestyle/CommonRulesetTest.php
@@ -62,6 +62,7 @@ public static function providePhp80Fixtures(): array
             ["blankLineBeforeStatement"],
             ["braces"],
             ["stringVariables"],
+            ["lowercaseKeywords"],
         ];
     }
 
diff --git a/tests/fixtures/lowercaseKeywords/actual.php b/tests/fixtures/lowercaseKeywords/actual.php
new file mode 100644
index 0000000..98b445e
--- /dev/null
+++ b/tests/fixtures/lowercaseKeywords/actual.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+Class LowercaseKeywordsTest Extends ObjectOperatorTest
+{
+    PUBLIC function test(): int
+    {
+        Foreach (range(1, 5) as $item) {
+            IF ($item > 3) {
+                Return 0;
+            }
+        }
+
+        RETURN 5;
+    }
+
+    public function testAnonymousClass(): void
+    {
+        new Class() EXTENDS LowercaseKeywordsTest {};
+    }
+}
diff --git a/tests/fixtures/lowercaseKeywords/expected.php b/tests/fixtures/lowercaseKeywords/expected.php
new file mode 100644
index 0000000..e74fa06
--- /dev/null
+++ b/tests/fixtures/lowercaseKeywords/expected.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+class LowercaseKeywordsTest extends ObjectOperatorTest
+{
+    public function test(): int
+    {
+        foreach (range(1, 5) as $item) {
+            if ($item > 3) {
+                return 0;
+            }
+        }
+
+        return 5;
+    }
+
+    public function testAnonymousClass(): void
+    {
+        new class() extends LowercaseKeywordsTest {};
+    }
+}