diff --git a/RELEASE_NOTES.rst b/RELEASE_NOTES.rst
index da3a324bd..3501397cd 100644
--- a/RELEASE_NOTES.rst
+++ b/RELEASE_NOTES.rst
@@ -4,6 +4,7 @@ Next release
 All changes
 -----------
 
+- :pull:`347`: Preserve dtypes of index columns in :func:`.data_for_quantity`.
 - :pull:`339`: ``ixmp show-versions`` includes the path to the default JVM used by JDBCBackend/JPype.
 - :pull:`317`: Make :class:`reporting.Quantity` classes interchangeable.
 - :pull:`330`: Use GitHub Actions for continuous testing and integration.