The Spirit Airlines carry-on baggage allowance is one small personal item; 18 x 14 x 8 inches (45 x 35 x 20 cm). A fee applies to bring an additional, larger item, with dimensions of 22 x 18 x 10 inches (56 x 46 x 25 cm).

The fee for bringing an additional item on board varies according to when the allowance is purchased - at initial booking, before/during check-in, at the airport, or at the gate. For most flights the fee is $65, one way, as standard, if purchased during online booking. If a passenger is a member of the Saver$ club*, they can purchase their carry-on allowance for $64. If, however, the allowance is purchased during online check-in, the cost is $75 as standard, or $74 for club members. The price increases to $89 at the airport, or $99 at the gate.