diff --git a/errors.go b/errors.go
index 09a8ce7c3..a04a4d17e 100644
--- a/errors.go
+++ b/errors.go
@@ -14,6 +14,10 @@ var (
 
 	// ErrMissingDirectory is returned when the path does not have an existing directory.
 	ErrMissingDirectory = errors.New("path needs to be an existing directory")
+
+	// ErrNamespaceNotAuthorized is returned when a user attempts to perform an action
+	// on a namespace (organization) they do not have access to.
+	ErrNamespaceNotAuthorized = errors.New("namespace not authorized")
 )
 
 // Options/fields that cannot be defined
diff --git a/gpg_key.go b/gpg_key.go
index 23a02533e..d4302efef 100644
--- a/gpg_key.go
+++ b/gpg_key.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"net/url"
+	"strings"
 	"time"
 )
 
@@ -127,6 +128,9 @@ func (s *gpgKeys) Update(ctx context.Context, keyID GPGKeyID, options GPGKeyUpda
 	g := &GPGKey{}
 	err = s.client.do(ctx, req, g)
 	if err != nil {
+		if strings.Contains(err.Error(), "namespace not authorized") {
+			return nil, ErrNamespaceNotAuthorized
+		}
 		return nil, err
 	}
 
diff --git a/gpg_key_integration_test.go b/gpg_key_integration_test.go
index bb9e7d274..c47a1f223 100644
--- a/gpg_key_integration_test.go
+++ b/gpg_key_integration_test.go
@@ -114,6 +114,18 @@ func TestGPGKeyUpdate(t *testing.T) {
 	// call. We'll need to manually delete the key.
 	gpgKey, _ := createGPGKey(t, client, org, provider)
 
+	t.Run("when using an invalid namespace", func(t *testing.T) {
+		keyID := GPGKeyID{
+			Namespace: provider.Organization.Name,
+			KeyID:     gpgKey.KeyID,
+		}
+		opts := GPGKeyUpdateOptions{
+			Namespace: "invalid_namespace_org",
+		}
+		_, err := client.GPGKeys.Update(ctx, keyID, opts)
+		assert.ErrorIs(t, err, ErrNamespaceNotAuthorized)
+	})
+
 	t.Run("when updating to a valid namespace", func(t *testing.T) {
 		// Create a new namespace to update the key with
 		org2, org2Cleanup := createOrganization(t, client)