diff --git a/CHANGES.md b/CHANGES.md
index 0818f64cda0..455eae9019d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -35,6 +35,9 @@ Fourth Release Candidate for Cylc 8 suitable for acceptance testing.
 
 ### Enhancements
 
+[#4877](https://github.com/cylc/cylc-flow/pull/4877) - Upgrade the version of
+Jinja2 used by Cylc from 2.11 to 3.0.
+
 [#4887](https://github.com/cylc/cylc-flow/pull/4887) - Disallow relative paths
 in `global.cylc[install]source dirs`.