Luggage in this range generally will fit in the carry-on compartment. The rule on domestic airlines is that the linear measurement of the piece -- length plus width plus height -- cannot exceed 45 inches for it to be a carry-on. A piece of luggage of this size generally can get you through a trip lasting four days -- more if you plan to wear outfits more than once. Most bags of this size come with compartments so you can separate your travel essentials.
Most people at an airport who are checking luggage have bags that are in the 24- to 26-inch range. Suitcases of this size are generally suitable for a four- to seven-day trip and may be used for longer getaways. A piece of luggage of this size will often have a separate, zippered area for hanging garments. You also will find 24- to 26-inch suitcases that are expandable in case you do a bit too much shopping and have more to pack on the way home.
Luggage in the 29-inch range can hold what you need for an extended trip lasting longer than a week. Be careful when purchasing luggage this large, though, because it may be difficult to pack the suitcase and stay within the weight limitations imposed by the airline. Most airlines add fees for bags weighing more than 50 lbs., so luggage this large may not be practical unless you have items that are especially tall -- and not necessarily heavy -- that you need to pack.
In addition to considering the length of the trip when buying luggage, you also should consider your size. Try out the luggage for a few minutes in the store. Wheel it around, carry it and make sure you are comfortable with it. See if it is easy to maneuver, and, if you plan to connect it to another piece of luggage, determine how that would work. For example, you couldn't put a 26-inch piece on top of a 29-inch, so you would need two hands to wheel them both.
