MINNEAPOLIS (WCCO) — “Cheap Flight Day” is here, which means it is time to start planning that vacation.

“It was cheaper, maybe $100 cheaper,” said Ruth Stefanic, who was flying from Minneapolis to Phoenix Tuesday.

Rick Seaney of farecompare.com says Tuesday marks the start of the fall travel season; a time when airlines begin to slash prices after summer high season.

“If you compare earlier this year in the spring, the prices can be up to 40-percent to 45-percent cheaper,” Seaney said.

Airlines are looking to fill empty seats after Labor Day when demand is down. Plus, domestic flights are a real bargain.

(credit: CBS)

(credit: CBS)

“If you’re paying over $210 roundtrip, you’re probably paying too much for your ticket,” Seaney said.

The best fares are listed Tuesday afternoons, Seaney says, when airlines battle to beat competitors.

If you are flexible on your dates, that will also work in your favor. Tuesdays, Wednesdays and Saturdays are the cheapest days to fly, but still buy your tickets as soon as possible.

“You don’t want to get caught up in being inside 14 days before a departure. The airlines will start treating you as if your boss is paying for your ticket and you can afford four-times more,” Seaney said.

He says consumers should be aware of “airline Christmas” — the last two weeks of December and the first week of January — when ticket prices will be much higher.

Same goes for the week around Thanksgiving. If you have to travel during those times, do not procrastinate.

Starting Tuesday, you can add a dollar to your ticket price each day you wait. Once you hit October, add $2 a day.