diff --git a/cmd/clusterctl/client/cluster/cert_manager.go b/cmd/clusterctl/client/cluster/cert_manager.go
index a679e3a5b0b5..137dc3dcd2ef 100644
--- a/cmd/clusterctl/client/cluster/cert_manager.go
+++ b/cmd/clusterctl/client/cluster/cert_manager.go
@@ -42,12 +42,6 @@ const (
 	waitCertManagerInterval = 1 * time.Second
 
 	certManagerNamespace = "cert-manager"
-
-	// This is maintained only for supporting upgrades from cluster created with clusterctl v1alpha3.
-	//
-	// Deprecated: Use clusterctlv1.CertManagerVersionAnnotation instead.
-	// TODO: Remove once upgrades from v1alpha3 are no longer supported.
-	certManagerVersionAnnotation = "certmanager.clusterctl.cluster.x-k8s.io/version"
 )
 
 var (