This is from WDW website:
Cancellation and Change fees
* For a cancellation made 44 to 6 days prior to arrival, there is an additional cancellation fee of $100 per package plus any cancellation fees assessed by hotels or other suppliers.
* For a cancellation made 5 days or less prior to arrival, there is an additional cancellation fee of $200 per package plus any cancellation fees by hotels or other suppliers. . In addition, with respect to Grand Gathering experiences, no refund will be given for cancellations made 5 days or less from the experience date. No refunds will be given to no-shows.
* For a change made 44 days or less prior to arrival or that results in a rate change, there is an additional change fee of $50 per package plus any change fees assessed by hotels or other suppliers.
* For changes, the change fees must be paid in addition to any increase in rate resulting from the change.
* In addition: If your air travel has been ticketed, there will be an additional cancellation or change fee per ticket equal to the cancellation or change fee assessed by the airline. Please note that (x) cancellation of a nonrefundable airfare results in a charge equal to the entire amount of the airfare and (y) cancellation of a refundable airfare must be made at least 1 business day prior to departure.
* Vacation insurance is nonrefundable if not cancelled within 14 days after booking (for bookings 14 days or less prior to arrival, vacation insurance is nonrefundable if not cancelled at least one day prior to arrival). Upon any cancellation, the charge for vacation insurance will be added to the other applicable cancellation fees.
* If you cancel, amounts paid, minus cancellation fees and other amounts owed, will be promptly refunded.
Change Procedure
* Changes affecting outbound flights or first night's accommodations must be made at least 6 business days prior to arrival. All existing documents must be returned to Walt Disney Travel Co., Inc. via overnight delivery service and revised documents will be delivered express at an additional cost of $10.
* Land portions of the booking cannot be cancelled without canceling the air reservations.
* Airlines/hotels/suppliers do not permit changes in certain situations.