diff --git a/internal/cli/config.go b/internal/cli/config.go
index 700390f2a3..ee432ea8c2 100644
--- a/internal/cli/config.go
+++ b/internal/cli/config.go
@@ -93,6 +93,7 @@ func (opts *configOpts) Run() error {
 				Help:    "This is the ID of an existing project your API keys have access to, you can leave this blank and specify it on every command with --projectId",
 				Default: config.ProjectID(),
 			},
+			Validate: validate.OptionalObjectID,
 		},
 	}
 
diff --git a/internal/validate/validate.go b/internal/validate/validate.go
index c3c9a7939f..9e7e890f68 100644
--- a/internal/validate/validate.go
+++ b/internal/validate/validate.go
@@ -24,23 +24,49 @@ import (
 	"github.com/mongodb/mongocli/internal/config"
 )
 
-func URL(val interface{}) error {
+// toString tires to cast an interface to string
+func toString(val interface{}) (string, error) {
 	var u string
 	var ok bool
 	if u, ok = val.(string); !ok {
-		return fmt.Errorf("'%v' is not a valid URL", val)
+		return "", fmt.Errorf("'%v' is not valid", val)
+	}
+	return u, nil
+}
+
+// URL validates a value is a valid URL for the cli store
+func URL(val interface{}) error {
+	s, err := toString(val)
+	if err != nil {
+		return err
 	}
-	if !strings.HasSuffix(u, "/") {
-		return fmt.Errorf("'%s' must have a trailing slash", u)
+	if !strings.HasSuffix(s, "/") {
+		return fmt.Errorf("'%s' must have a trailing slash", s)
 	}
-	_, err := url.ParseRequestURI(u)
+	_, err = url.ParseRequestURI(s)
 	if err != nil {
-		return fmt.Errorf("'%s' is not a valid URL", u)
+		return fmt.Errorf("'%s' is not a valid URL", s)
 	}
 
 	return nil
 }
 
+// OptionalObjectID validates a value is a valid ObjectID
+func OptionalObjectID(val interface{}) error {
+	if val == nil {
+		return nil
+	}
+	s, err := toString(val)
+	if err != nil {
+		return err
+	}
+	if s == "" {
+		return nil
+	}
+	return ObjectID(s)
+}
+
+// ObjectID validates a value is a valid ObjectID
 func ObjectID(s string) error {
 	b, err := hex.DecodeString(s)
 	if err != nil || len(b) != 12 {
@@ -49,6 +75,7 @@ func ObjectID(s string) error {
 	return nil
 }
 
+// Credentials validates public and private API keys have been set
 func Credentials() error {
 	if config.PrivateAPIKey() == "" || config.PublicAPIKey() == "" {
 		return errors.New("missing credentials")
diff --git a/internal/validate/validate_test.go b/internal/validate/validate_test.go
index bea49402c0..06177e0b50 100644
--- a/internal/validate/validate_test.go
+++ b/internal/validate/validate_test.go
@@ -42,6 +42,39 @@ func TestURL(t *testing.T) {
 	})
 }
 
+func TestOptionalObjectID(t *testing.T) {
+	t.Run("Empty value", func(t *testing.T) {
+		err := OptionalObjectID("")
+		if err != nil {
+			t.Fatalf("OptionalObjectID() unexpected error %v\n", err)
+		}
+	})
+	t.Run("nil value", func(t *testing.T) {
+		err := OptionalObjectID(nil)
+		if err != nil {
+			t.Fatalf("OptionalObjectID() unexpected error %v\n", err)
+		}
+	})
+	t.Run("Valid ObjectID", func(t *testing.T) {
+		err := OptionalObjectID("5e9f088b4797476aa0a5d56a")
+		if err != nil {
+			t.Fatalf("OptionalObjectID() unexpected error %v\n", err)
+		}
+	})
+	t.Run("Short ObjectID", func(t *testing.T) {
+		err := OptionalObjectID("5e9f088b4797476aa0a5d56")
+		if err == nil {
+			t.Fatal("OptionalObjectID() expected an error\n")
+		}
+	})
+	t.Run("Invalid ObjectID", func(t *testing.T) {
+		err := OptionalObjectID("5e9f088b4797476aa0a5d56z")
+		if err == nil {
+			t.Fatal("OptionalObjectID() expected an error\n")
+		}
+	})
+}
+
 func TestObjectID(t *testing.T) {
 	t.Run("Valid ObjectID", func(t *testing.T) {
 		err := ObjectID("5e9f088b4797476aa0a5d56a")