diff --git a/renderdoc/serialise/codecs/xml_codec.cpp b/renderdoc/serialise/codecs/xml_codec.cpp
index 548f0a724..858bc451c 100644
--- a/renderdoc/serialise/codecs/xml_codec.cpp
+++ b/renderdoc/serialise/codecs/xml_codec.cpp
@@ -477,6 +477,7 @@ static RDResult Structured2XML(const rdcstr &filename, const RDCFile &file, uint
     SDChunk *chunk = chunks[c];
 
     xChunk.append_attribute("id") = chunk->metadata.chunkID;
+    xChunk.append_attribute("chunkIndex") = c;
     xChunk.append_attribute("name") = chunk->name.c_str();
     xChunk.append_attribute("length") = chunk->metadata.length;
     if(chunk->metadata.threadID)