diff --git a/jetty-util/src/main/java/org/eclipse/jetty/util/StringUtil.java b/jetty-util/src/main/java/org/eclipse/jetty/util/StringUtil.java
index e0ffafaafbf..6c183a5d36d 100644
--- a/jetty-util/src/main/java/org/eclipse/jetty/util/StringUtil.java
+++ b/jetty-util/src/main/java/org/eclipse/jetty/util/StringUtil.java
@@ -585,6 +585,7 @@ public class StringUtil
      * @param sidBytes the SID bytes to build from
      * @return the string SID
      */
+    @Deprecated
     public static String sidBytesToString(byte[] sidBytes)
     {
         StringBuilder sidString = new StringBuilder();
@@ -634,6 +635,7 @@ public class StringUtil
      * @param sidString the string SID
      * @return the binary SID
      */
+    @Deprecated
     public static byte[] sidStringToBytes( String sidString )
     {
         String[] sidTokens = sidString.split("-");
diff --git a/jetty-util/src/test/java/org/eclipse/jetty/util/StringUtilTest.java b/jetty-util/src/test/java/org/eclipse/jetty/util/StringUtilTest.java
index 23cd7896cbd..2eb897d01b5 100644
--- a/jetty-util/src/test/java/org/eclipse/jetty/util/StringUtilTest.java
+++ b/jetty-util/src/test/java/org/eclipse/jetty/util/StringUtilTest.java
@@ -143,6 +143,7 @@ public class StringUtilTest
     }
 
     @Test
+    @Deprecated
     public void testSidConversion() throws Exception
     {
         String sid4 = "S-1-4-21-3623811015-3361044348-30300820";