diff --git a/Magento2/Sniffs/Commenting/ClassPropertyPHPDocFormattingSniff.php b/Magento2/Sniffs/Commenting/ClassPropertyPHPDocFormattingSniff.php
index 3732e2ac..0913be26 100644
--- a/Magento2/Sniffs/Commenting/ClassPropertyPHPDocFormattingSniff.php
+++ b/Magento2/Sniffs/Commenting/ClassPropertyPHPDocFormattingSniff.php
@@ -32,6 +32,7 @@ class ClassPropertyPHPDocFormattingSniff extends AbstractVariableSniff
         T_NULLABLE,
         T_BITWISE_AND,
         T_TYPE_UNION,
+        T_READONLY,
     ];
 
     /**
diff --git a/Magento2/Tests/Commenting/ClassPropertyPHPDocFormattingUnitTest.inc b/Magento2/Tests/Commenting/ClassPropertyPHPDocFormattingUnitTest.inc
index cde71269..aca8a73b 100644
--- a/Magento2/Tests/Commenting/ClassPropertyPHPDocFormattingUnitTest.inc
+++ b/Magento2/Tests/Commenting/ClassPropertyPHPDocFormattingUnitTest.inc
@@ -200,4 +200,14 @@ class correctlyFormattedClassMemberDocBlock
      * @deprecated This property will be removed in version 1.0.0 without replacement
      */
     protected string $deprecatedWithKeyword;
+
+    /**
+     * @var string
+     */
+    protected readonly string $readOnlyString;
+
+    /**
+     * @var int
+     */
+    protected readonly int $readOnlyInteger;
 }