Traveling during the holidays can be a nightmare. You have to navigate through busy airports and sit on crowded planes, and there are frequently delays.

Now, add higher baggage prices to the list of frustrations.

This holiday season, it's going to cost you more to check a bag if you're flying low-fare airlines Spirit or Frontier.

"It's like all these companies have their hands out, and you have to pay before you can continue," said Michael Bowlander, who was traveling through Tampa International Airport. "It's getting a little ridiculous."

Sen. Bill Nelson, D-Florida, recently sent a letter to every airline, urging them to halt any plans they may have to charge higher fees.

"It's important somebody stand up and speak out for the traveling public," Nelson said.

If you're flying Spirit, there's an extra $2 fee on all checked bags between Dec. 16 and Jan. 4. The airline said that's because the higher travel demand brings added costs of fuel and handling baggage.

"During times of peak travel, such as the summer months and holidays, there is much more demand for checked bags," Spirit Airlines spokesman Paul Berry said. "This demand brings added costs for baggage handling, manpower, airport infrastructure and added weight to aircraft, which burns more jet fuel."

Berry said only charging those who check bags is a more fair and transparent approach than raising ticket prices.

Frontier Airlines is charging passengers $5–$10 extra per carry-on and checked bag between Nov. 19 and Jan. 5, but the airline isn't calling it an increase.

"These are our standard prices, and we offer a discount in other periods, and we changed our pricing model earlier this year, "Frontier Airlines President Barry Biffle said. "I think the whole premise that Frontier has done something bad to consumers around the holiday is just unfair and completely deceptive and sensational, when the truth is anything but."

Both airlines said even with the higher baggage fees, it's still cheaper to fly with them than their competitors.

But it still doesn't sit well with some travelers.

"If we start getting charged for carry-ons, then what are we doing to do?" Bowlander wondered.