Free Contract Addendum Templates

What Is a Contract Addendum?

An Addendum to a Contract is a legal document that serves to add information that was not included in the main body of the original agreement. In most cases, an Addendum is completed and becomes effective after the main document, being an extension to the original contract. It serves to clarify, change, or nullify a portion of the original document.

When an Addendum template is filled out, you need to reference the original document, name all the parties that signed it, and indicate the clauses and terms the Addendum alters. If you add new information or even entire sections to your agreement, for example, if the landlord allows the tenant to have pets in the house, you may number it with a reference to a section that lists rights and responsibilities of the parties (Section 6), giving it number 6.1.

Below you may find the most popular types of Addendums. Browse the library of forms to find and fill out the one you need:

  1. Addendum to a Contract. This supplemental document represents an agreed-upon addition to the original contract, signed by all the parties. It leaves the contract in full force and only changes some specific terms and conditions.
  2. Addendum to Lease. Complete this document to make changes to an existing commercial or residential lease agreement. Whether you are a landlord or tenant, you may wish to add roommate expectations or lawn care policies using an Addendum.
  3. Pet Addendum. This legal document establishes the agreement between a landlord and a tenant about having pets in the house or apartment. With it, you may agree upon pet-related rules that become a legally binding part of the residential lease or rental agreement.
  4. Mold Addendum. The owner of the property may use this document to notify the tenant of their responsibility to prevent mold in a leased property. Before you sign this Addendum, make sure there are no areas in the apartment or house where mold exists.

Addendum Vs. Amendment

When changing or adding new information to an agreement, parties may choose between an Amendment and an Addendum. Amending a contract means making changes to the original document, while an Addendum means drafting an additional document as an attachment to the original agreement. An Amendment constitutes a modification since it alters the original document. For example, the parties may change the price for a product or extend the term of the contract.

On the other hand, an Addendum usually covers information that was left out when the agreement was originally signed – for instance, the individual signs a contract to buy an unfurnished house, but then offers the seller to pay an additional amount of money to keep furniture and appliances already in place.

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Need to add an additional section to a previously signed contract? Check out this document to add to the agreement while still keeping the primary contract intact.

This type of amendment to a Lease Agreement defines the terms on which pets are allowed on the lease.

This document can be added to a Lease Agreement in order to outline certain rules, which are not covered by the original agreement.

A Mold Addendum is a document attached to a Lease Agreement. It's needed for leasing a building or other property that has certain requirements for keeping it clean of mold.

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