Get ready to pay more for your Thanksgiving flight

Andrew Harrer | Bloomberg | Getty Images

Travelers wait in line before going through Transportation Security Administration screening at Ronald Reagan National airport in Washington, D.C.

The days of rock-bottom Thanksgiving airfares are over.

Roundtrip domestic U.S. flights are about 13 percent more expensive this year than in 2016, fetching about $325 on average as of this week, according to fare-tracking site Hopper.

Airlines factor demand and their costs when they set their fares.

Jet fuel is more than 20 percent more expensive than at the same point last year, according to S&P Global Platts. Disruptions following Hurricane Harvey, which struck a key refining region in Texas, has kept prices aloft even during the slowdown in air travel following the busy summer season.

The good news is fares will likely remain stable throughout October, but usually spike around $10 a day in the two weeks leading up to Thanksgiving, according to Hopper.

A little flexibility goes a long away, especially if the whole family is flying. Flights on Thanksgiving Day are averaging $54 less than on the Wednesday before. The Sunday after the holiday will be the busiest day at airports and flights are averaging $48 more than for flights leaving the next day.

Passengers will also find that even if they snag a great fare, they might not receive the same perks as they did last year. American Airlines and United Airlines rolled out basic economy class, which in exchange for the cheapest seats on the plane, deny passengers use of overhead bins or seat selection.

American Airlines’ president Robert Isom told investors on Thursday that the new class of service was “not a price cut” but rather encouraged many passengers to pay the premium for regular economy class.