On the payment page, on the right-hand side, under your cart summary, you can apply a promo code. You can use your promo code if it's valid. Please check if your promocode has not expired and that all the promocode´s conditions advertised are met. You can use only one at a time, they are not cumulative. Promocodes are not applicable for some products, please check point 9 of Terms & Conditions. It cannot be applied to bookings previously made. It can only be used via the online payment method.