Summertime, Easter and especially the week between Christmas and New Year's are the busiest times of the year. Unless you want a lot of company on the road, at hotels and in the parks, don't go then. Orlando never really has a "slow season," but there are a couple of lulls. From May 1 through June 15, before the summer rush starts, is one. The second half of August through the end of September, when more families are focused on back-to-school than taking a trip, is also a slower time.