It pays to travel light.
A survey by USA Today of airline fees shows that some carriers have hit or surpassed the $400 mark for international passengers traveling with overweight baggage.
On most international flights Continental is charging $400 for a bag weighing 71-100 pounds. United Airlines similarly charges $400 for bags weighing 71-99.9 pounds on intercontinental flights.
American Airlines will charge you $450 for overweight luggage bound for Asia. The reason, AA spokesman Tim Smith told USA Today's Ben Mutzabaugh, was to both defray fuel costs and to dissuade passengers from checking such heavy bags in the first place.
The annual USA TODAY survey of 13 U.S. carriers also found fees for a first checked bag are up to $38 for domestic flights and $43 for international.
Want to avoid a checked-bag fee? Spirit Airlines will still charge you a $40 fee for carrying your own bag on board, though they'll give you a break (a $30 fee) if you warn them in advance via their website.
The survey found fees to make a change to a ticket vary. Frontier Airlines charges $50 for an international flight change; Delta Air Lines and United charge $150 for domestic, approx. $250 for international.
Booking a "free" frequent flier rewards ticket? It'll cost you. Most airlines charge for booking a rewards tickets with an agent over the phone; some will still charge if you book it yourself online. The highest reward ticket booking fees are US Airways', from $25-$50 (online) to $55-$90 (on the phone).
Airlines say that their fee structure helps keep ticket prices low, and allow fliers to pay only for those services that they use, writes USA Today's Mutzabaugh.
For more on the USA Today survey and a guide to carrier fees, click here.