diff --git a/java-overridable/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdater.java b/java-overridable/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdater.java
index c97a0d232..8b66cff53 100644
--- a/java-overridable/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdater.java
+++ b/java-overridable/src/com/android/inputmethod/latin/personalization/PersonalizationDictionaryUpdater.java
@@ -16,8 +16,6 @@
 
 package com.android.inputmethod.latin.personalization;
 
-import java.util.Locale;
-
 import android.content.Context;
 
 import com.android.inputmethod.latin.DictionaryFacilitator;
@@ -33,12 +31,7 @@ public class PersonalizationDictionaryUpdater {
         mDictionaryFacilitator = dictionaryFacilitator;
     }
 
-    public Locale getLocale() {
-        return null;
-    }
-
-    public void onLoadSettings(final boolean usePersonalizedDicts,
-            final boolean isSystemLocaleSameAsLocaleOfAllEnabledSubtypesOfEnabledImes) {
+    public void onLoadSettings(final boolean usePersonalizedDicts) {
         if (!mDictCleared) {
             // Clear and never update the personalization dictionary.
             PersonalizationHelper.removeAllPersonalizationDictionaries(mContext);
diff --git a/java/src/com/android/inputmethod/latin/DictionaryFacilitator.java b/java/src/com/android/inputmethod/latin/DictionaryFacilitator.java
index e1acf3da8..46428839f 100644
--- a/java/src/com/android/inputmethod/latin/DictionaryFacilitator.java
+++ b/java/src/com/android/inputmethod/latin/DictionaryFacilitator.java
@@ -189,6 +189,10 @@ public class DictionaryFacilitator {
         mPersonalizationDictionaryFacilitator.updateEnabledSubtypes(enabledSubtypes);
     }
 
+    public void setIsMonolingualUser(final boolean isMonolingualUser) {
+        mPersonalizationDictionaryFacilitator.setIsMonolingualUser(isMonolingualUser);
+    }
+
     public Locale getLocale() {
         return mDictionaryGroup.mLocale;
     }
@@ -600,7 +604,7 @@ public class DictionaryFacilitator {
             final SpacingAndPunctuations spacingAndPunctuations,
             final AddMultipleDictionaryEntriesCallback callback) {
         mPersonalizationDictionaryFacilitator.addEntriesToPersonalizationDictionariesToUpdate(
-                personalizationDataChunk, spacingAndPunctuations, callback);
+                getLocale(), personalizationDataChunk, spacingAndPunctuations, callback);
     }
 
     public void addPhraseToContextualDictionary(final String[] phrase, final int probability,
diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index 67e2ca5c7..d2104997c 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -614,9 +614,10 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
 
     private void refreshPersonalizationDictionarySession(
             final SettingsValues currentSettingsValues) {
-        mPersonalizationDictionaryUpdater.onLoadSettings(
-                currentSettingsValues.mUsePersonalizedDicts,
+        mDictionaryFacilitator.setIsMonolingualUser(
                 mSubtypeSwitcher.isSystemLocaleSameAsLocaleOfAllEnabledSubtypesOfEnabledImes());
+        mPersonalizationDictionaryUpdater.onLoadSettings(
+                currentSettingsValues.mUsePersonalizedDicts);
         mContextualDictionaryUpdater.onLoadSettings(currentSettingsValues.mUsePersonalizedDicts);
         final boolean shouldKeepUserHistoryDictionaries;
         if (currentSettingsValues.mUsePersonalizedDicts) {
@@ -734,10 +735,6 @@ public class LatinIME extends InputMethodService implements KeyboardActionListen
                 cleanupInternalStateForFinishInput();
             }
         }
-        // TODO: Remove this test.
-        if (!conf.locale.equals(mPersonalizationDictionaryUpdater.getLocale())) {
-            refreshPersonalizationDictionarySession(settingsValues);
-        }
         super.onConfigurationChanged(conf);
     }
 
diff --git a/java/src/com/android/inputmethod/latin/PersonalizationDictionaryFacilitator.java b/java/src/com/android/inputmethod/latin/PersonalizationDictionaryFacilitator.java
index 03c108f0e..aa8e312a4 100644
--- a/java/src/com/android/inputmethod/latin/PersonalizationDictionaryFacilitator.java
+++ b/java/src/com/android/inputmethod/latin/PersonalizationDictionaryFacilitator.java
@@ -44,6 +44,7 @@ public class PersonalizationDictionaryFacilitator {
     private final HashMap<String, HashSet<Locale>> mLangToLocalesMap = new HashMap<>();
     private final HashMap<Locale, ExpandableBinaryDictionary> mPersonalizationDictsToUpdate =
             new HashMap<>();
+    private boolean mIsMonolingualUser = false;;
 
     PersonalizationDictionaryFacilitator(final Context context,
             final DistracterFilter distracterFilter) {
@@ -81,6 +82,10 @@ public class PersonalizationDictionaryFacilitator {
         }
     }
 
+    public void setIsMonolingualUser(final boolean isMonolingualUser) {
+        mIsMonolingualUser = isMonolingualUser;
+    }
+
     /**
      * Flush personalization dictionaries to dictionary files. Close dictionaries after writing
      * files except the dictionary that is used for generating suggestions.
@@ -141,12 +146,18 @@ public class PersonalizationDictionaryFacilitator {
         personalizationDict.addMultipleDictionaryEntriesDynamically(languageModelParams, callback);
     }
 
-    public void addEntriesToPersonalizationDictionariesToUpdate(
+    public void addEntriesToPersonalizationDictionariesToUpdate(final Locale defaultLocale,
             final PersonalizationDataChunk personalizationDataChunk,
             final SpacingAndPunctuations spacingAndPunctuations,
             final AddMultipleDictionaryEntriesCallback callback) {
-        final HashSet<Locale> locales =
-                mLangToLocalesMap.get(personalizationDataChunk.mDetectedLanguage);
+        final String language = personalizationDataChunk.mDetectedLanguage;
+        final HashSet<Locale> locales;
+        if (mIsMonolingualUser && PersonalizationDataChunk.LANGUAGE_UNKNOWN.equals(language)
+                && mLangToLocalesMap.size() == 1) {
+            locales = mLangToLocalesMap.get(defaultLocale.getLanguage());
+        } else {
+            locales = mLangToLocalesMap.get(language);
+        }
         if (locales == null || locales.isEmpty()) {
             if (callback != null) {
                 callback.onFinished();
diff --git a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDataChunk.java b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDataChunk.java
index 6f4b09741..734ed5583 100644
--- a/java/src/com/android/inputmethod/latin/personalization/PersonalizationDataChunk.java
+++ b/java/src/com/android/inputmethod/latin/personalization/PersonalizationDataChunk.java
@@ -20,6 +20,8 @@ import java.util.Collections;
 import java.util.List;
 
 public class PersonalizationDataChunk {
+    public static final String LANGUAGE_UNKNOWN = "";
+
     public final boolean mInputByUser;
     public final List<String> mTokens;
     public final int mTimestampInSeconds;