US low-cost carrier Spirit Airlines is considering linking the additional fees, such as for preferred seats and checked luggage, paid by passengers to demand for seats on the flight.
However, such an arrangement is at least a few months away if it is adopted at all.
This will lead to higher fees during the peak travel days and lower prices on slow days, according to media reports.
Spirit currently charges additional fees on the basis of the timing of the selection and payment of the fee. Customers who wait until they are at the airport are charged the most.
Spirit is one of the few US airlines to charge customers for selecting a pre-flight seat assignment. The airline also charges for water, placing a bag in the overhead bin and printing a boarding pass at the airport.
Currently, United and Delta base their charges for extra-legroom seats according to their calculations on demand for the flight.