diff --git a/telephony/java/android/telephony/CarrierConfigManager.java b/telephony/java/android/telephony/CarrierConfigManager.java
index 3ef11f1632906..b559247b9d2ab 100755
--- a/telephony/java/android/telephony/CarrierConfigManager.java
+++ b/telephony/java/android/telephony/CarrierConfigManager.java
@@ -1805,6 +1805,13 @@ public class CarrierConfigManager {
     public static final String KEY_SUPPORT_DIRECT_FDN_DIALING_BOOL =
             "support_direct_fdn_dialing_bool";
 
+    /**
+     * Int indicating the max number length for FDN
+     * @hide
+     */
+    public static final String KEY_FDN_NUMBER_LENGTH_LIMIT_INT =
+            "fdn_number_length_limit_int";
+
     /**
      * Report IMEI as device id even if it's a CDMA/LTE phone.
      *
@@ -3315,6 +3322,7 @@ public class CarrierConfigManager {
         sDefaults.putBoolean(KEY_CDMA_HOME_REGISTERED_PLMN_NAME_OVERRIDE_BOOL, false);
         sDefaults.putString(KEY_CDMA_HOME_REGISTERED_PLMN_NAME_STRING, "");
         sDefaults.putBoolean(KEY_SUPPORT_DIRECT_FDN_DIALING_BOOL, false);
+        sDefaults.putInt(KEY_FDN_NUMBER_LENGTH_LIMIT_INT, 20);
         sDefaults.putBoolean(KEY_CARRIER_DEFAULT_DATA_ROAMING_ENABLED_BOOL, false);
         sDefaults.putBoolean(KEY_SKIP_CF_FAIL_TO_DISABLE_DIALOG_BOOL, false);
         sDefaults.putBoolean(KEY_SUPPORT_ENHANCED_CALL_BLOCKING_BOOL, true);