Christmas decorations at the Walt Disney World Resort usually begin going up around the first of November. The decorations are gradually added at night and are substantially complete at Magic Kingdom by the time of the first Mickey’s Very Merry Christmas Party (in 2018, that will be November 8), with the resorts and other parks completed by the day after Thanksgiving. read more
The Christmas tree in the Magic Kingdom will not go up until after the taping of the Christmas Parade the first weekend in December. Dad's Disney Christmas Parade page The decorations stay up through the first Saturday in January. read more
When the park closes that night, the Halloween decorations immediately begin to come down, and the Christmas decorations go up in their place. Cast Members must work quickly & magically adding Christmas decorations throughout the Parks and Disney Resorts each night. read more