The Magic Date to Fly for Summer Vacation

June 8, 2014— -- I won't keep you in suspense: The magic date to fly this summer is August 25. The magical part is how much money you can save.

If you can't fly on the exact date, don't worry. You can fly later.

Not convenient?

You might change your mind after looking at some of these ticket prices. I'll also show you ways to make it easier to get in on the magic.

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Summertime ranks right up there with Thanksgiving as one of the most expensive times to fly, but you know that. What you may not know is how when it airline summer ends. The exact date varies a little year by year (and sometimes from airline to airline), but in 2014, the last day of Airline Summer is August 24. The magic date that kicks off the cheaper fall season is Aug. 25 when prices drop by 10 to 20 percent. Sometimes even more.

It's all about the kids. Because so many of them go back to school in late August, that effectively ends vacation season for many families. With the decreased demand, airlines resort to sales to fill up their planes during fall doldrums and they want you to think about it now: This past week alone, four major airlines launched fall sales, all good for travel beginning Aug. 25.

Some of the prices were amazing.

United Airlines' sale, for example, included one-way fares from San Francisco to Las Vegas for $49. Fly that route in July and you'll pay $119, an increase of 140 percent!

By the way, for our friends in the U.K. and elsewhere in Europe: You, too, will see prices drop around this date for transatlantic flights.

But saving money isn't the only perk to flying Aug. 25 or later. Airport crowds start to melt away then which usually means a faster security experience and you'll probably see fewer cars heading to Yosemite and fewer folks lining up for the Louvre (although winter is the best time for many tourist attractions). Disney, of course, never runs short of congested queues but it won't be quite as crowded starting in late August and maybe it won't be quite as hot in Southern California or Central Florida, either.

One more perk: Hotels will be cheaper too, as long as you can avoid major holidays.

The best way to put together such a magically cheaper trip is the obvious way: Depart and return after Aug. 25. If that's not possible, see if you can shoehorn your return flight into the magic zone so at least you'll reap half the savings (but this does not work for international travel, all of which must take place on or after the magic date). Note: You'll never hear me say take the kids out of school to grab the savings, but I understand some parents do this - in the interests of 'educational trips', of course.

But if traveling on or after Aug. 25 is simply not do-able, don't despair. Here are a few ways to ease your travel costs and crowding.

-- Sign up for PreCheck or Global Entry: The cost of these programs is $16 and $20 per year respectively (membership is good for five years) which buys you a faster security experience through TSA checkpoints (no need to remove shoes or jackets), and Global Entry is additionally helpful for international returns.

-- Compare non-stops with connecting flights: Adding a stop or two often significantly lowers the price of airline tickets, but not always which is why you must compare airfares by route.

-- Fly and drive: If you don't live near a big hub airport consider flying out of the nearest one even if it's a long drive. The savings might be worth it.

-- Avoid flights on Fridays and Sundays: Those are the usually the most expensive days to fly. In general, the cheapest days are Tuesdays, Wednesdays and Saturdays.

-- If you really want to save and don't mind a longer wait, try flying during the first two weeks of November or in the last three weeks of January. These are the Dead Zones of travel when most flights are as cheap as they ever get.

Opinions expressed in this column are solely those of the author and not those of ABC News.