Yes, you will almost always pay significantly more for luggage if you add it to your Ryanair reservation after the initial booking is completed. In 2026, Ryanair’s "dynamic pricing" model rewards those who plan ahead; adding a 10kg or 20kg checked bag during the first checkout process is a high-value strategy that can save you between €15 and €25 per bag compared to adding it later. If you wait until you get to the airport or the check-in counter, the "post-booking" fees can skyrocket to over €40–€60 per bag. For a premier budget experience, it is a "pro-move" to weigh your bags at home and purchase the necessary allowance during the first transaction on the app or website. Ryanair also limits the number of "Priority & 2 Cabin Bags" slots per flight, so waiting to add baggage post-booking may not only cost more but could also result in your preferred baggage option being sold out entirely.