diff --git a/telephony/java/android/telephony/CarrierConfigManager.java b/telephony/java/android/telephony/CarrierConfigManager.java
index 1762eb7..3eedce6 100644
--- a/telephony/java/android/telephony/CarrierConfigManager.java
+++ b/telephony/java/android/telephony/CarrierConfigManager.java
@@ -3935,6 +3935,13 @@
     public static final String KEY_NETWORK_TEMP_NOT_METERED_SUPPORTED_BOOL =
             "network_temp_not_metered_supported_bool";
 
+    /**
+     * Indicates whether RTT is supported while roaming.
+     * @hide
+     */
+    public static final String KEY_RTT_SUPPORTED_WHILE_ROAMING_BOOL =
+            "rtt_supported_while_roaming_bool";
+
     /** The default value for every variable. */
     private final static PersistableBundle sDefaults;
 
@@ -4290,6 +4297,7 @@
         sDefaults.putBoolean(KEY_RTT_SUPPORTED_BOOL, false);
         sDefaults.putBoolean(KEY_TTY_SUPPORTED_BOOL, true);
         sDefaults.putBoolean(KEY_HIDE_TTY_HCO_VCO_WITH_RTT_BOOL, false);
+        sDefaults.putBoolean(KEY_RTT_SUPPORTED_WHILE_ROAMING_BOOL, false);
         sDefaults.putBoolean(KEY_DISABLE_CHARGE_INDICATION_BOOL, false);
         sDefaults.putBoolean(KEY_SUPPORT_NO_REPLY_TIMER_FOR_CFNRY_BOOL, true);
         sDefaults.putStringArray(KEY_FEATURE_ACCESS_CODES_STRING_ARRAY, null);