diff --git a/res/values/strings.xml b/res/values/strings.xml
index 04374c4..281e890 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -1256,6 +1256,8 @@
        &lt;br>&lt;br> - RTT calls are saved as a message transcript
        &lt;br> - RTT is not available for video calls</string>
 
+    <string name="no_rtt_when_roaming">Note: RTT is not available while roaming</string>
+
     <!-- Service option entries.  -->
     <string-array name="tty_mode_entries">
         <item>TTY Off</item>
diff --git a/src/com/android/phone/settings/AccessibilitySettingsFragment.java b/src/com/android/phone/settings/AccessibilitySettingsFragment.java
index cff9c0a..3069091 100644
--- a/src/com/android/phone/settings/AccessibilitySettingsFragment.java
+++ b/src/com/android/phone/settings/AccessibilitySettingsFragment.java
@@ -28,6 +28,7 @@
 import android.telephony.PhoneStateListener;
 import android.telephony.SubscriptionManager;
 import android.telephony.TelephonyManager;
+import android.text.TextUtils;
 import android.util.Log;
 
 import com.android.ims.ImsManager;
@@ -113,6 +114,11 @@
         if (shouldShowRttSetting()) {
             // TODO: this is going to be a on/off switch for now. Ask UX about how to integrate
             // this settings with TTY
+            if (TelephonyManager.getDefault().isNetworkRoaming(
+                    SubscriptionManager.getDefaultVoiceSubscriptionId())) {
+                mButtonRtt.setSummary(TextUtils.concat(getText(R.string.rtt_mode_summary), "\n",
+                        getText(R.string.no_rtt_when_roaming)));
+            }
             boolean rttOn = Settings.Secure.getInt(
                     mContext.getContentResolver(), Settings.Secure.RTT_CALLING_MODE, 0) != 0;
             mButtonRtt.setChecked(rttOn);