woocommerce_form_field in the foreach loop https://github.com/woocommerce/woocommerce/blob/master/templates/checkout/form-billing.php#L39 refers to https://github.com/woocommerce/woocommerce/blob/master/includes/wc-template-functions.php#L2607 So you can adapt the following code to your needs function change_woocommerce_field_markup( $field, $key, $args, $value ) { // Remove the .form-row class from the current field wrapper $field = str_replace(‘form-row’, ”, $field); // Wrap the field (and its wrapper) in a new custom div, adding … Read more