If your travel plans include a plane ride, buy your tickets as soon as you can.

I learned that lesson the hard way a few weeks ago. My wife and I are going to Hawaii in December We had planned to take advantage of Alaska Airlines promotional fare for its new non-stop service from Seattle to Maui: $498 round trip.

But I got busy the week the promotional fare expired and had to pay more. When I finally had the time to get online, I found the cheapest seats I could get were $599.40. That one week delay cost me $100 bucks per ticket.

And that $599 price is a bargain compared to the cheapest tickets I could find for those same flights this weekend: $758.90. Yikes!

And as the plane fills up, the price for the last seats will go even higher.

To deal with soaring jet fuel prices, airlines have raised fares or fuel surcharges at least 10 times this year. Some plan to fly fewer planes. That will reduce the number of seats available, and let them boost prices even more.

Yes, you can sometimes get a great last minute deal online. Sometimes. But if you need to get from here to there on a specific date, especially if it's a popular route -- you'll pay if you delay.