Yes, you can add baggage to a Ryanair booking at any time up until approximately two hours before your flight's scheduled departure via the Ryanair website or mobile app. In 2026, it is significantly cheaper to add bags online during the initial booking or even several days later through the "Manage My Booking" portal than it is to do so at the airport. At the airport check-in desk, the fees for adding a 10kg or 20kg checked bag can be double or triple the online price. To add a bag later, you simply log in to your "MyRyanair" account, select your upcoming trip, and click "Add bags/equipment." You can choose between a 10kg "Check-in Bag" (which must be dropped at the desk) or a 20kg bag. Note that if you have already checked in for your flight online, you can still add baggage, but you may need to re-download or re-print your boarding pass to reflect the updated details. Ryanair's dynamic pricing means the cost of adding a bag may slightly increase as the departure date approaches, so earlier is always better.