diff --git a/docs/Changelog.md b/docs/Changelog.md
index 238caddcf4b..13157fc1180 100644
--- a/docs/Changelog.md
+++ b/docs/Changelog.md
@@ -33,6 +33,7 @@ based on merged pull requests. Search GitHub issues and pull requests for smalle
 - Ignore negative travel-times in Raptor [#5443](https://github.com/opentripplanner/OpenTripPlanner/pull/5443)
 - Fix sort order bug in optimized transfers [#5446](https://github.com/opentripplanner/OpenTripPlanner/pull/5446)
 - Siri file loader [#5460](https://github.com/opentripplanner/OpenTripPlanner/pull/5460)
+- Calculate CO₂ emissions of itineraries [#5278](https://github.com/opentripplanner/OpenTripPlanner/pull/5278)
 [](AUTOMATIC_CHANGELOG_PLACEHOLDER_DO_NOT_REMOVE)
 
 ## 2.4.0 (2023-09-13)