Explore Spirit Airlines Baggage Policy to make your travel smoother. One personal item such as a small purse or backpack is free for travelers on Spirit Airlines. There are additional costs for checked and carry-on bags which vary according on your itinerary and payment time. Check before packing since there may be restrictions on bag size and weight. Bags that are overweight or large may incur additional fees. To keep your travel stress-free and prevent surprises at the airport prepare ahead of time and familiarize yourself with the regulations.