• Low Season: May 1 to July 15 & from August 31 to October 15
• Medium Season: March 16 to April 30 & Nov 1 to December 21
• High Season: July 15 to August 31 & December 22 to March 15

Many good deals can be found during low season and also at the end of medium seasons as the travel industry try to jump start the peak seasons. Supply and demand rules prices though ... prices will rise quickly if it starts to sell out (for example, many people from Europe and South America travel to Cuba during the summer).

There are periods during high and medium that have brief sell offs, usually to fill the planes.  It is perceived that the resorts are filling but in fact it is the planes (limited amount of flights per charter company) - the end of January and early Feb is one of these times.