The best time to cruise and the cheapest time to cruise are not always the same.
The best time to be on the water is often when the weather is nicest or when you have time off. These sailings are often the most popular, but “best” can quickly turn to “worst” when you face high prices and large crowds.
The cheapest time to cruise is often when most travelers don’t want to go. You may find less ideal weather or some seasonal closures, but the lure of cheap fares and uncrowded ports might make you change your mind about what you consider the best time to cruise. See more at Source: The cheapest and best times to go to 7 popular cruise destinations