diff --git a/subcommands/keys/ca_renewal_revoke_root.go b/subcommands/keys/ca_renewal_revoke_root.go
new file mode 100644
index 00000000..fffc908b
--- /dev/null
+++ b/subcommands/keys/ca_renewal_revoke_root.go
@@ -0,0 +1,51 @@
+package keys
+
+import (
+	"os"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+
+	"github.com/foundriesio/fioctl/client"
+	"github.com/foundriesio/fioctl/subcommands"
+	"github.com/foundriesio/fioctl/x509"
+)
+
+var serialToRevoke string
+
+func init() {
+	cmd := &cobra.Command{
+		Use:   "revoke-root <PKI Directory>",
+		Short: "Revoke an inactive root CA for your Factory PKI",
+		Run:   doRevokeRootRenewal,
+		Args:  cobra.ExactArgs(1),
+		Long: `Revoke an inactive root CAA for your Factory PKI.
+
+This command removes a Root CA with a given serial and associated cross-signed CA certificates.
+After that point a given Root CA can no longer be re-activated.
+Devices which were not updated with a new Root CA will instantly lose connectivity to Foundries.io services.
+
+This action is irreversible, so plan properly as to when you perform it.
+It is usually the last step of the Root CA rotation, which is optional unless your old Root CA was compromised.`,
+	}
+	caRenewalCmd.AddCommand(cmd)
+	cmd.Flags().StringVarP(&serialToRevoke, "serial", "", "",
+		"A serial number of the Root CA to revoke in hexadecimal format")
+	_ = cmd.MarkFlagRequired("serial")
+	addStandardHsmFlags(cmd)
+}
+
+func doRevokeRootRenewal(cmd *cobra.Command, args []string) {
+	factory := viper.GetString("factory")
+	certsDir := args[0]
+	subcommands.DieNotNil(os.Chdir(certsDir))
+	hsm, err := validateStandardHsmArgs(hsmModule, hsmPin, hsmTokenLabel)
+	subcommands.DieNotNil(err)
+	x509.InitHsm(hsm)
+
+	toRevoke := map[string]int{serialToRevoke: x509.CrlRootRevoke}
+	// The API will determine and revoke cross-signed certificates as well.
+	// It will also check that a user is not revoking a currently active Root CA.
+	req := client.CaCerts{RootRevokeCrl: x509.CreateCrl(toRevoke)}
+	subcommands.DieNotNil(api.FactoryPatchCA(factory, req))
+}
diff --git a/x509/common.go b/x509/common.go
index 37bf691c..608f618b 100644
--- a/x509/common.go
+++ b/x509/common.go
@@ -41,6 +41,12 @@ const (
 
 	// CRL constants for root CA revokation.
 
+	// Revoke the root CA, so that it is no longer available in the root CAs list.
+	// Note: the API will revoke the root CA for any reason other than 4, 6, or 8.
+	// Reasons 6 and 8 are ignored.
+	// This action is permanent.
+	CrlRootRevoke = 5 // RFC 5280 - cessationOfOperation
+
 	// Supersede the root CA by another root CA.
 	// This is used to switch the currently active root CA, used to sign/verify device CAs and TLS certificates.
 	// The superseded CA serial be a currently active root CA, and the CRL must be signed by a newly activated root CA.