An addendum is a change or addition attached to a real estate contract. It indicates terms that were not included in the original contract of purchase or sale. The addendum must be part of the original contract. Changes that occur after contracts have been signed are referred to as amendments. All parties must agree to the terms of the addendum before the contracts are considered complete. One example of an addendum is a buyer requesting that an appliance, such as a dishwasher, be included with the sale of the home. Another might ask for closing cost assistance from the seller. An addendum may be used when the sale of the home is contingent on certain factors, such as verification of buyer financing or confirmation that the home is not in a known flood zone.