Leah Noel of St. Paul has reached her tipping point. At $400 a ticket for airfare from MSP to Pittsburgh, she's considering driving 16 hours each way for her family to see her husband's parents rather than pay $1,600 for four round-trip fares. "We can save $1,000 if we drive," she said.

Last year, she paid about $300 per ticket to Pittsburgh, and two years ago it was $250, Noel said. She checked four airlines, alternate airports and flights with stops, but all of the fares were $400 to $500 per ticket.

Many domestic fliers are discovering that $400 is the new $300. It's getting harder to fly from MSP to almost anywhere for under $400, said travel guru Terry Trippler. "You can get to Chicago for less but not to Las Vegas anymore," he said. "The $198 round-trip fares are gone."

The reason prices have gone up is fewer seats on fewer flights but the same number of fliers, said Peter Greenberg, travel editor for CBS News. "If you don't believe me, ask yourself when was the last time you flew when it wasn't a full flight?" Many people assume that prices are up due to higher fuel costs, but those costs are about the same as last year, Greenberg said.

We're also our own enemies, with most of us willing to pay up to $500 for a domestic ticket, according to a Travel Leaders Group survey. Eighteen percent of those surveyed said $600 was their tipping point. Only a funeral, medical need or wedding could make people pay more than their self-imposed limit, according to the survey.

You can try to beat the system.

Flexible travelers willing to add stops and fly midweek can pay less than $400, but the cheapest airfares have risen by 18 percent between January 2011 and May 2012, according to Rick Seaney at Farecompare.com.

Those who can wait until August to travel should see lower fares. Most families crunch their summer air travel into June and July. "Families willing to delay air travel until mid-August or so can save 20 percent or more," said Tom Parsons, CEO of Bestfares.com.

WAYS TO SAVE

Delay summer travel until August or September. Watch for sales this month for travel in August or later. September is especially slow after school starts.

Depart from airports in Duluth or Rochester if flying to Europe. In a recent check, Parsons said, a traveler could have saved $150 by flying from Rochester to London on Delta instead of from MSP.

Fly Tuesdays and Wednesdays instead of Fridays and Sundays. The kids are out of school anyway and parents can enjoy a shorter workweek by returning to work on a Thursday.

Shop for fares on Tuesdays or Wednesdays. Sale fares are posted then and competitors have had time to match or beat them, according to Parsons. Still, sale fares can pop up almost any weekday, so keep your eyes open.

Call airline reservations for prices. Don't limit your search to online, said Greenberg. Airlines often have last-minute cancellations and reservationists are the first to know about those.

Take advantage of the 24-hour cancellation policy. Nearly all airlines allow cancellations and refunds of reservations within 24 hours of booking, even on nonrefundable fares. Making a reservation prevents the airline from raising the fare several hours later when you return to the search on the same computer.

Check low fares at budget airlines including Spirit and Southwest.

Sign up for daily fare alerts to cities you want to visit. Tripadvisor.com, Farecompare.com, Travelocity.com, Kayak.com and Airfarewatchdog.com have them.

John Ewoldt • 612-673-7633 or jewoldt@startribune.com. If you spot a deal, share it at www.startribune.com/dealspotter.