Source: Randy Robertson via Flickr.

We've all seen the last minute airfare deals that sites advertise in our email inbox. But if you've tried to book those deals you probably quickly discovered that the advertised deal was too good to be true, applied only to an obscure flight, or had too many restrictions.

Most of the time, booking last minute is the most expensive way to fly. However, there are good ways to travel last minute, and a few cities are consistently worth visiting if you're booking a trip on short notice.

Where to fly on a moment's notice
Cities like Atlanta, New York, and San Francisco can result in a 50% savings if you buy three weeks in advance of traveling instead of just a week before, so last minute travelers should try to avoid flying there. On the other hand, destinations like Hawaii, Mexico/Caribbean, and Asia Pacific don't need as much planning according to Expedia's (NASDAQ:EXPE) recent report Preparing for Takeoff: Air Travel Trends 2015.

Source: Expedia's Preparing for Takeoff: Air Travel Trends 2015.

Hawaii doesn't need much planning ahead at all. Planning a trip three weeks in advance, when the typical optimal purchasing window begins to close, results in just a 3% savings versus buying a ticket one week in advance.

If you're flying to Mexico/Caribbean and Asia Pacific, planning ahead will save you just 7% and 13%, respectively.

Last-minute travels to these destinations are still more costly than planning a few weeks ahead, but if you're willing to search out deals, the odds are good that you can still find a flight for cheap.

Source: Expedia's Preparing for Takeoff: Air Travel Trends 2015.

Deals that could disappear at a moment's notice
Sometimes flights can be cheap on a moment's notice, but a trip may still be expensive. The cost of a hotel room or rental car can more than offset flight savings, especially last minute. That's why you should consider bundling hotels, rental cars, and anything else you need when you book a flight, just to make sure you get a complete trip. On flights to Hawaii and the Caribbean bundling on last minute flights can save you a lot.

According to Expedia's report, package savings for Maui are $1,307.82, or 26.1% of the trip's cost, and in Riviera Maya in Mexico savings are $1,019.24, or 21.9%. Cancun and Los Cabos are also great for package trips. 

Not only will getting a package save you money, it will give you peace of mind that with a single click you've booked everything you need for a great vacation.

Traveling on short notice
It's often very expensive to travel at the last minute, but not all locations are out of reach if you're planning a trip on short notice. Hawaii, Mexico, the Caribbean, and Asia Pacific are all relatively cheap up to a week before a flight, and if you're looking for a vacation there could be worse places to fly.