To enter a discount code on the London North Eastern Railway (LNER) website or app in 2026, you must first select your journey and proceed to the "Review your journey" or "Payment" screen. Unlike some retail sites, the promo code box is often hidden until you are logged into an LNER account. Look for a link that says "Add a promo code" or "Do you have a discount code?" just before the final "Pay Now" button. For specific discounts like the "Alumni" or "Friends and Family" offers, the discount is often applied automatically if you book through a dedicated portal or link provided in your email. If you are using a Railcard, this is selected at the very beginning of the search process in the "Passengers" section, rather than being entered as a code at the end of the transaction.