1. Surcharges for Human Contact
Don't laugh, but American Airlines charges $25 if you buy your ticket over the phone and speak to a human being. Worse, if you buy your ticket in person, at their counter, the charge goes up to $35.
How to avoid: Buy your ticket online.
2. Carry-On Charges
Spirit Airlines led the pack when it came to charging for carry-ons: $30 (at the time of online booking), $35 (at online check in) or $40-$45 per bag (counter check-in ticket purchase).
How to avoid: Get a carry-on that fits under your seat (dimensions vary, but for most planes, 19 inches wide x 17 deep x 9.5 or 10 tall will work). For now, under-seat carry-ons are still free on most airlines.
3. Checked-Baggage Fees
Most airlines charge $25 for the first checked bag and $35 to $40 for the second.
How to avoid: If you're traveling in the United States, ship your bags ahead via the U.S. Postal Service - it takes time and planning but can save money and frustration. You also have a paper trail and even insurance.