diff --git a/spanner/CHANGES.md b/spanner/CHANGES.md
index c54c491..c94a9da 100644
--- a/spanner/CHANGES.md
+++ b/spanner/CHANGES.md
@@ -1,5 +1,12 @@
 # Changes
 
+## [1.21.0](https://www.github.com/googleapis/google-cloud-go/compare/spanner/v1.20.0...spanner/v1.21.0) (2021-06-23)
+
+
+### Miscellaneous Chores
+
+* **spanner:** trigger a release for low cost instance ([#4264](https://www.github.com/googleapis/google-cloud-go/issues/4264)) ([24c4451](https://www.github.com/googleapis/google-cloud-go/commit/24c4451404cdf4a83cc7a35ee1911d654d2ba132))
+
 ## [1.20.0](https://www.github.com/googleapis/google-cloud-go/compare/spanner/v1.19.0...spanner/v1.20.0) (2021-06-08)