Yes, you can typically purchase Delta Priority Boarding (often marketed as "Priority Boarding" or included in "Trip Extras") even after you have checked in for your flight, provided the limit for that flight hasn't been reached. In 2026, the easiest way to do this is through the Fly Delta app. Simply go to your "Trip" view, and if available, you will see an option to "Upgrade" or "Add Extras." Buying this will move you to Zone 5 (the first zone for Main Cabin passengers), allowing you to find overhead bin space before the plane gets crowded. However, if you have already checked in and are at the gate, you may not be able to buy it through the app if boarding has already begun. In 2026, Delta also integrates these offers into their "SkyMiles" dashboard, sometimes allowing you to pay for the priority boost using points instead of cash, though the value per point is usually lower for these small "add-on" purchases.