United Airlines started it all back in March, announcing that it would charge $15 for a second checked bag on domestic flights. From there, the trend escalated — airlines' way of dealing with rising fuel prices.

Now some carriers charge passengers for all checked luggage, and many have raised their overweight and oversize fees. Even bags that are allowed free of charge must, in most cases, weigh 50 pounds or less, and the sum of a bag's length, width and height must be 62 inches or less. To prevent passengers from dragging big bags into the cabin, some airlines are becoming more vigilant about carry-ons as well.

Most major airlines have a "one bag and one personal item" rule. Below are the fees that several major carriers charge for oversize and overweight baggage, as well as new checked-bag fees and size limits for carry-ons. Note that a bag may be subject to a triple whammy of charges if it's too large, too heavy and one too many. Maybe you don't need all those shoes.

AMERICAN

Bag charges: First: $15. Second: $25. Third to fifth: $100 each. Sixth: $200.

Overweight bag fees: 51 to 70 pounds: $50. 71 to 100 pounds: $100.

Oversize bag fees: 63 to 115 inches: $150.

Carry-on limit: 45 inches and 40 pounds.

CONTINENTAL

Bag charges: First: free. Second: $25. Third: $100.

Overweight bag fees: 51 to 70 pounds: $50.

Oversize bag fees: 63 to 115 inches: $100.

Carry-on limit: 51 inches and 40 pounds.

DELTA

Bag charges: Domestic — First: free. Second: $25. Third to 10th: $80 to $180 each. International — First and second: free. Third to 10th: $150 to $600 each.

Overweight bag fees: 51 to 70 pounds: $80. 71 to 100 pounds: $150.

Oversize bag fees: 62 to 80 inches: $150.

Carry-on limit: 45 inches and 40 pounds.

NORTHWEST

Bag charges: First: $15. Second: $25. Third: $100.

Overweight bag fees: 51 to 70 pounds: $50.

Oversize bag fees: Domestic — 63 to 80 inches: $100. International varies.

Carry-on limit: 45 inches.

UNITED (FEES AS OF AUG. 18)

Bag charges: Domestic — First: $15. Second: $25. Third and additional: $125 to $250 each. International varies.

Overweight bag fees: 51 to 100 pounds: $125.

Oversize bag fees: 63 to 115 inches: $125.

Carry-on limit: 45 inches.

U.S. AIRWAYS

Bag charges: First: $15. Second: $25. Third and additional: $100 each.

Overweight bag fees: 51 to 70 pounds: $50 to $150; 71 to 100 pounds: $100 to $200 (based on number of bags).

Oversize bag fees: 62 to 80 inches: $100.

Carry-on limit: 51 inches.