/* WooCommerce < 3.0.4 */
add_filter(‘woocommerce_checkout_fields’,’reorder_fields’);
function reorder_fields($fields) {
$billing_field_order = array(
‘billing_first_name’,
‘billing_last_name’,
‘billing_address_1’,
‘billing_email’,
‘billing_phone’,
‘billing_country’,
‘billing_state’,
‘billing_city’,
‘billing_district’,
‘billing_postcode’
);
$shipping_field_order = array(
‘shipping_first_name’,
‘shipping_last_name’,
‘shipping_address_1’,
‘shipping_email’,
‘shipping_phone’,
‘shipping_country’,
‘shipping_state’,
‘shipping_city’,
‘shipping_district’,
‘shipping_postcode’
);
$ordered_billing_fields = array();
$ordered_shipping_fields = array();
foreach ($billing_field_order as $field) {
$ordered_billing_fields[$field] = $fields[‘billing’][$field];
}
foreach ($shipping_field_order as $field) {
$ordered_shipping_fields[$field] = $fields[‘shipping’][$field];
}
$fields[‘billing’] = $ordered_billing_fields;
$fields[‘shipping’] = $ordered_shipping_fields;

return $fields;
}

sudah add hook di function.php urutannya tinggal field postcode masih nyelip di bawah field provinsi..