Форум

 $basket = \Bitrix\Sale\Basket::loadItemsForFUser(
   \CSaleBasket::GetBasketUserID(),
   "s1"
);

$order = Bitrix\Sale\Order::create("s1", \Bitrix\Sale\Fuser::getId());
$order->setPersonTypeId(1);
$order->setBasket($basket);

$discounts = $order->getDiscount();
$res = $discounts->getApplyResult();
$price = $order->getPrice();