Pocket up to $40 in luggage fees. Jet Blue and Southwest are the only major domestic airlines that don’t charge travelers $15 to $20 each way for their first checked bag. On other airlines, pay for only one piece of luggage by sharing a bag with your spouse or travel companion.

Either way, be sure to keep the bag’s weight below 50 pounds to avoid overweight luggage charges, which can range from $49 to $175. And lastly, to save an additional $5, pay baggage fees ahead of time online, when you print out the boarding pass for your flight.