First Class is a specific "cabin of service" (the actual seat you sit in), while Delta Sky Priority is a "suite of services" designed to speed up your airport experience. If you are flying in First Class, you automatically receive Sky Priority benefits, but the reverse is not always true. First Class provides a wider seat, more legroom, premium meals, and dedicated flight attendant service. Sky Priority, on the other hand, includes "ground" benefits: dedicated check-in lanes, accelerated security lines (where available), priority boarding, and expedited baggage handling, ensuring your bags are among the first on the carousel. In 2026, Sky Priority is also available to Delta's high-tier frequent flyers (Platinum and Diamond Medallion) even when they are flying in the Main Cabin. Essentially, First Class is about the luxury on the plane, while Sky Priority is about the efficiency at the airport. You can be a "Sky Priority" passenger sitting in the very last row of the plane if you have the right status, but you won't get the First Class meal or legroom.