Between shelling out hundreds of dollars in airfare and forking over even more for ancillary fees, travelers are already spending more than they have in years for plane tickets. And that’s about to get worse.

Starting on July 21, the Transportation Security Administration — you know, the folks who are in charge of confiscating your shampoo at the airport and taking you aside for an “additional screening” — will more than double the mandatory fee they charge many passengers and will no longer cap these fees. Under the old law, the fee, which is used for security, was $2.50 for each leg of a flight with a $5 cap on each one-way trip or a $10 cap on each round trip. But beginning July 21, the fee is $5.60 for each leg of a flight and that is not capped; if your layover is more than four hours on a domestic flight or 12 hours for international destinations, that counts as a second leg of the flight and you will be charged an additional fee.

While that may not sound like a lot, consider what this could mean for your wallet. If you book a domestic round trip and have two total connections (and the layover is four hours or more during each connection), you’ll end up shelling out nearly $25 to the TSA. That jacks up the average domestic airline ticket price by more than 5%.

This move will hurt all travelers — as the fees are mandatory and built into ticket prices — and it could especially hurt business travelers, says George Hobica, founder of AirfareWatchdog.com. That’s because business travelers often take multicity round trips — a round trip simply means any trip where the traveler leaves and returns from the same spot, so a traveler could stop in a city for a day or two, as many do — and will now have to pay a fee (and now there’s no cap on those fees) on each leg. The TSA uses the examples of a traveler who takes a round trip flight to and from Newark with stops in Chicago, Denver and Las Vegas and pays $28 in fees; before, that would have only been $10. It could also particularly impact those who live in small towns and have to take connecting flights, says Victoria Day, a spokeswoman for Airlines for America, a trade group that represents many large airlines; for the same reason, budget travelers who get superlow fares in exchange for taking flights with connections might also be especially impacted.

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The higher fees — which will generate an estimated extra $16.9 billion over the next 10 years, according to the government — are slated to help pay for flyer security, and it’s hard to argue against that notion; and the TSA notes that the current fees have never fully covered its costs. There is still a chance that the fee change will be overturned if Congress acts, says Hobica. Plus, even though these fees have increased significantly, they are still a small part of travelers’ overall airline ticket bill.

Still, these fees are likely to anger consumers, as they come amid rising ticket prices and fees and as flying becomes more unpleasant. Since 2010, average domestic airfare, adjusted for inflation, has climbed more than 6% to nearly $382. Plus, airlines have been upping and adding ancillary fees left and right: Just this year, Frontier began making passengers pay to put their bags in the overhead bin and Spirit raised their baggage fees. And this all comes at a time when airline seats are getting thinner and less padded so that airlines can save on fuel.

Though there isn’t much you can do about these fees other than write your congressman to complain, says Hobica — MarketWatch has a few suggestions.

To offset the fees, try to cut the cost of the plane ticket by using a site like Hopper.com that tells you the best time to book for optimal deals or by creating fare alerts on the search engines.

Travelers can also opt to book direct flights (but those are often more expensive) or those with short layovers.

And they also may want to consider having someone drive them to a larger, nearby airport that has direct flights to avoid these fees, but with gas included, just make sure that makes economic sense.

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