Travel Tips: When is the best time to book a flight?

Working in the travel business, I naturally get a lot of travel questions from people. And a question that comes up fairly often is when is a good time of day to schedule a flight to ensure on-time arrival and lower fares?
Flights that take off in the morning and originate at your departure airport are going to depart and arrive as timely as possible. As the day goes on, flights tend to back up, and you run the risk of arriving later.
Morning, however, is not the least expensive time to travel. Typically, if you’re flying to places that are business destinations (New York City, Boston, L.A., etc.), the Monday through Friday early morning and early evening flights are going to be the most expensive.
The best way to get the very best fare is to call the airline and ask about the lowest rate between Point A and Point B, and what you have to do to get this price. If you’re flexible, make sure you tell them so, and you should only offer up the approximate time you need to travel.
For example, "I’m flexible. I want to go from Philadelphia to Miami sometime in March." The agent will tell you the best fare available, and if you call several airlines operating that service, you’ll soon discover what the best rates are and how to get them.
The same works for online booking sites. By clicking the "I’m flexible" button, you can compare the various fares available at the cheapest times. If you’re willing to do your homework, chances are you’ll be able to find a great deal no matter where you’re headed.