US budget carrier Spirit Airlines is cutting the amount of space allocated to passenger luggage, The Independent reports.

Known for its “pay as you go” model of combining inexpensive base fares with fees for nearly any conceivable travel-related “extra, Spirit’s base fare includes the ability to carry onboard a single piece of luggage.

But the airline is reducing by 25 per cent the size of luggage permitted under its cheapest fares, from 2,688 cubic inches to 2,016 cubic inches.

Passengers who show up at the boarding gate with bags that don’t fit in that space will be charged a $100 fee to bring their luggage along on the flight. Spirit passengers may also pay fees of $26 and up in advance in order to bring bigger bags onboard. To avoid the issue entirely, you can choose to check your luggage, but the Spirit fee for that starts at $50 per bag.

Other airlines that compete with Spirit, including major carriers like American Airlines and United Airlines, have also started to restrict the ability to carry luggage onboard for travellers who purchase their lowest-priced seats.

Spirit Airlines flies in the US, the Caribbean, and Latin America.