If you’ve been staying home to avoid peak summer prices, start packing; the cheapest dates for summer fares are just a few weeks away.

The magic dates

Aug. 22 is when average U.S. domestic fares get cheaper; Aug. 21 is when average trans-Atlantic ticket prices will drop. In effect, these dates are the start of the air travel industry’s fall season: When children go back to school, demand takes a dive which prompts the airlines to lower their fares. Fall is cheap and, where airfares are concerned, fall arrives in August.

How much you can save

This varies quite a bit depending on departure and destination cities, and whether routes are non-stops or connections, but generally you can save an average of 11% to 20% over summer ticket prices.

Here are some examples of round-trip fares found July 13. The departure/return dates for the summer fares are Aug. 8-15 while the fall fares are for Aug. 22-29 itineraries.

Seattle-Dallas
•    Summer: $294
•    Fall: $277

Chicago-Orlando
•    Summer: $181
•    Fall: $158

Los Angeles-New York
•    Summer: $647
•    Fall: $399

New York-Paris
•    Summer: $680
•    Fall: $470

Best days of the week to fly in August and beyond

Aug. 22 falls on a Tuesday, generally one of the cheapest days for domestic flights (along with Wednesday and Saturday). The cheap day for international flights, Aug. 21, falls on a Monday and weekdays are generally cheaper than weekends for flying to Europe (but not always, so be sure to compare fares for different days).

As always, airfares change without notice so prices shown here may have gone up (or down) in the past few days but generally you can find better deals by flying in late August and beyond (well, up until Thanksgiving anyway).

FareCompare CEO Rick Seaney is an airline industry insider and top media air travel resource. Follow Rick (@rickseaney) and never overpay for airfare again.