diff --git a/src/config.rs b/src/config.rs
index 6b31566..a1f7737 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -149,6 +149,8 @@ pub enum FeatureFlag {
 	DryRun,
 	/// If only deactivated users should be synced
 	DeactivateOnly,
+	/// Use plain localpart
+	PlainLocalpart,
 }
 
 #[derive(Debug, Clone, Deserialize, PartialEq, Default)]
@@ -356,7 +358,10 @@ mod tests {
 		let file_path = create_config_file(tempdir.path());
 
 		let env_var_name = format!("{ENV_VAR_CONFIG_PREFIX}__FEATURE_FLAGS");
-		env::set_var(&env_var_name, "sso_login verify_email verify_phone dry_run deactivate_only");
+		env::set_var(
+			&env_var_name,
+			"sso_login verify_email verify_phone dry_run deactivate_only plain_localpart",
+		);
 
 		let loaded_config =
 			Config::new(file_path.as_path()).expect("Failed to create config object");
@@ -367,6 +372,7 @@ mod tests {
 		sample_config.feature_flags.push(FeatureFlag::VerifyPhone);
 		sample_config.feature_flags.push(FeatureFlag::DryRun);
 		sample_config.feature_flags.push(FeatureFlag::DeactivateOnly);
+		sample_config.feature_flags.push(FeatureFlag::PlainLocalpart);
 
 		env::remove_var(env_var_name);
 
diff --git a/src/zitadel.rs b/src/zitadel.rs
index 5761a06..a7d2406 100644
--- a/src/zitadel.rs
+++ b/src/zitadel.rs
@@ -408,6 +408,27 @@ impl Zitadel {
 			return Ok(());
 		}
 
+		let id = match &user.user_data.external_user_id {
+			StringOrBytes::String(value) => value.as_bytes(),
+			StringOrBytes::Bytes(value) => value,
+		};
+
+		let uuid;
+		let localpart = if self.feature_flags.contains(&FeatureFlag::PlainLocalpart) {
+			match &user.user_data.external_user_id {
+				StringOrBytes::String(value) => value,
+				StringOrBytes::Bytes(_) => {
+					bail!(
+						"Unsupported binary external ID for user using plain localparts: {:?}",
+						user
+					);
+				}
+			}
+		} else {
+			uuid = Uuid::new_v5(&FAMEDLY_NAMESPACE, id).to_string();
+			&uuid
+		};
+
 		let new_user_id = self
 			.zitadel_client
 			.create_human_user(&self.zitadel_config.organization_id, user.clone().into())
@@ -422,17 +443,12 @@ impl Zitadel {
 			)
 			.await?;
 
-		let id = match &user.user_data.external_user_id {
-			StringOrBytes::String(value) => value.as_bytes(),
-			StringOrBytes::Bytes(value) => value,
-		};
-
 		self.zitadel_client
 			.set_user_metadata(
 				Some(&self.zitadel_config.organization_id),
 				new_user_id.clone(),
 				"localpart".to_owned(),
-				&Uuid::new_v5(&FAMEDLY_NAMESPACE, id).to_string(),
+				localpart,
 			)
 			.await?;