Fare Class

Fare class (or "booking class", "RBD" — Reservation Booking Designator) is a single-letter code on every airline ticket that determines its pricing tier, mileage earning rate, refundability, and elite-status bonus eligibility.

Standard cabin mappings: Y, B, M, H, K = Economy (full to discount); W, P, S = Premium Economy; J, C, D, I, Z = Business; F, A, P = First. But each airline customizes — American’s "Q" is a discount Economy fare, Delta’s "Q" is a Comfort+ fare.

On the receipt, the fare class typically prints next to the route: "DL 142 Y class LAX-JFK". The class drives the elite-status earning rate (deeper-discount Y fares earn fewer miles than full-fare Y, sometimes only 25-50%).

Award tickets (paid with miles) show as "X class" or similar at most carriers. They earn no miles and are typically non-refundable except for cancel-for-miles redeposit.