What is a supplementary agreement?

A supplementary agreement (also called an addendum or amendatory agreement) is a document that modifies, adds to, or clarifies specific terms of an existing primary agreement without replacing the original contract.

Common Uses in Real Estate

• Extension of possession date developer informing buyer of a revised timeline.
• Revised payment plan restructuring instalment dates.
• Modification of specifications change in materials, design, or features.
• Addition of car parking or storage unit to the original purchase.
• Correction of minor errors in the original agreement.

Legal Status of a Supplementary Agreement

A supplementary agreement is binding only if both parties sign it voluntarily and the consideration (if any) is documented. It must be read together with the original agreement as a single composite document.

Supplementary agreements are routine in multi-year property purchases where circumstances evolve during the construction period. However, buyers should carefully read every supplementary agreement before signing particularly those proposed by developers regarding possession delays as they may inadvertently waive rights under RERA.