Spirit Airlines has dirt-cheap fares, but there’s a catch—you’ll pay for checked bags. Here are all of the baggage fees you can expect when flying with Spirit.

On all Spirit flights starting Aug. 1, any carry-on item placed in an overhead bin will cost passengers $30. Members of the airline's "fare club," who pay $39.95 a year for discounts, will pay $20.

Spirit Airlines will charge as much as $45 each way for a carry-on bag, adding a fee that bigger airlines have yet to try. The charge will apply to bags in the overhead bin. Personal items that ...

Airlines are usually clear about what is - and what isn't - a personal item. For example, American defines it as a purse or small handbag that must fit under the seat in front of you.

The fee applies to carry-ons placed in overhead bins, while personal items placed under the seat remain free. Spirit will charge $45 for these bags at the gate and $30 when paid in advance.

How to pack for a Spirit Airlines flight Commuting reporter Joseph Rose shows how to pack a "personal item" bag for a trip on Spirit Airlines so you don't have to pay up $100 more for a carry-on bag.