How to save money on cruises * Book as early as possible. Some passengers book a couple of years in advance for the best prices, according to industry watcher CruiseGuy.com. * Or book late. If a particular cruise doesn't fill up, and if your schedule is flexible, you might get a big bargain. Your travel agent will find the best deal for you. * Skip the Christmas cruise, New Year's week and spring break when kids are out of school. Prices are the highest, say agents at Expedia CruiseShip Centers in Plantation, Fla. * Book a May or September cruise. During these off-season dates, cruises are usually the least expensive. The best and most popular ships won't reduce prices very much. * Reserve in January through March (called the Wave Season) when cruise lines offer deals to lock in business for the year. The lines may also throw in a cabin upgrade, or a special free dinner.