diff --git a/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryKeyIndex.java b/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryKeyIndex.java
index 1f163308ab..5cf315573e 100644
--- a/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryKeyIndex.java
+++ b/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryKeyIndex.java
@@ -64,7 +64,16 @@ public void addTypeIndex(PrimaryKey primaryKey) {
     }
 
     public HollowHistoryTypeKeyIndex addTypeIndex(PrimaryKey primaryKey, HollowDataset dataModel) {
+        HollowHistoryTypeKeyIndex prevKeyIdx = typeKeyIndexes.get(primaryKey.getType());
         HollowHistoryTypeKeyIndex keyIdx = new HollowHistoryTypeKeyIndex(primaryKey, dataModel);
+        // retain any previous indexed fields
+        if (prevKeyIdx != null) {
+            for (int i = 0; i < prevKeyIdx.getKeyFields().length; i++) {
+                if (prevKeyIdx.getKeyFieldIsIndexed()[i]) {
+                    keyIdx.addFieldIndex(prevKeyIdx.getKeyFields()[i], dataModel);
+                }
+            }
+        }
         typeKeyIndexes.put(primaryKey.getType(), keyIdx);
         return keyIdx;
     }
diff --git a/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryTypeKeyIndex.java b/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryTypeKeyIndex.java
index 314b65ff04..d6852bcb67 100644
--- a/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryTypeKeyIndex.java
+++ b/hollow/src/main/java/com/netflix/hollow/tools/history/keyindex/HollowHistoryTypeKeyIndex.java
@@ -78,6 +78,10 @@ public String[] getKeyFields() {
         return primaryKey.getFieldPaths();
     }
 
+    public boolean[] getKeyFieldIsIndexed() {
+        return keyFieldIsIndexed;
+    }
+
     public void addFieldIndex(String fieldName, HollowDataset dataModel) {
         String[] fieldPathParts = PrimaryKey.getCompleteFieldPathParts(dataModel, primaryKey.getType(), fieldName);
         for (int i = 0; i < primaryKey.numFields(); i++) {