Contracts are legal documents that memorialise an agreement between parties. Contracts are recognised by courts as legal instruments expressing the will of the parties and must be honoured unless there are compelling reasons to ignore the terms of the agreement. Drafting contract language can be a challenge, even to the most skilled legal experts. Often, the legal content of a contract must be supplemented or modified through the use of an addendum. An addendum is a page that is added to the end of a contract to either more fully explain information in the contract or to modify the terms therein.
Determine what information will be on the addendum. Decide whether the addendum changes a provision in the contract or whether it will give additional information. You must also decide if the addendum will be referenced within the contract itself (this may not be possible if the contract has already been drafted and signed by the parties).
Write the addendum. The addendum should have a title that is centred on the page from left to right. If there is more than one, it should have a number or letter (Addendum I or Addendum A). If the addendum is being attached to an existing contract, add language to the addendum two lines below the title to this effect: "This is an addendum to the contract between [names of the parties] dated [date of original contract]. Place the information for the addendum directly on the page or attach it to the title page for the addendum, if your addendum is a series of pages.
Obtain the signatures of all of the parties to the original contract. This step is only necessary if the addendum modifies or suppresses the terms of the original contract. Be sure to have each signature notarised. If one of the parties is an entity, make sure that the individual signing on behalf of the entity has the requisite power to enter into the modification (signatures must be from officers of the entity and subject to authorisation through a resolution of the board of directors of the entity).