Spirit Carry-on Baggage Fees.
Unlike most legacy airlines such as Alaska, American, and Delta, Spirit Airlines does not provide a free carry-on bag.

Spirit carry-on baggage fees, like those for checked bags, vary from flight to flight. If you add a carry-on bag at the time of booking, you can expect to pay around $43 each way. In fact, Spirit baggage fees are typically higher for a carry-on bag than for a larger bag checked. If you do not pay for a carry-on bag, your boarding pass will indicate that you are not permitted to bring one
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