diff --git a/charts/cert-manager/templates/NOTES.txt b/charts/cert-manager/templates/NOTES.txt
index 341d101..4d0b4b6 100644
--- a/charts/cert-manager/templates/NOTES.txt
+++ b/charts/cert-manager/templates/NOTES.txt
@@ -1,6 +1,12 @@
 {{- if .Values.installCRDs }}
 ⚠️  WARNING: `installCRDs` is deprecated, use `crds.enabled` instead.
+
 {{- end }}
+⚠️  WARNING: New default private key rotation policy for Certificate resources.
+The default private key rotation policy for Certificate resources was
+changed to `Always` in cert-manager >= v1.18.0.
+Learn more in the [1.18 release notes](https://cert-manager.io/docs/releases/release-notes/release-notes-1.18).
+
 cert-manager {{ .Chart.AppVersion }} has been deployed successfully!
 
 In order to begin issuing certificates, you will need to set up a ClusterIssuer