What Is a Purchase Addendum in Real Estate?

A purchase addendum (also called a contract addendum) is a written document that modifies, adds to, or clarifies terms in the original purchase agreement. It becomes legally binding once both buyer and seller sign it.

✅ What Does a Purchase Addendum Do?

  • Changes existing terms (price, closing date, possession timeline).
  • Adds new conditions such as an inspection contingency or repair agreements.
  • Documents agreed repairs after inspection or discovery of material defects.
  • Clarifies responsibilities, such as who pays closing costs or concessions.
  • Extends deadlines for financing, inspections, appraisal, or escrow.

Addendums are commonly used when negotiating repairs, price changes, and updated timelines.

💡 Why Purchase Addendums Matter for FSBO Sellers

  • Protects both parties: Ensures changes are documented, not verbal.
  • Reduces legal risk: Prevents misunderstandings about repairs or credits.
  • Required for lender approval: Some changes must appear in writing for underwriting.
  • Common in repair negotiations: After inspection, buyers often submit addendums listing repair requests.
  • Needed for price updates: Any price change must be documented through an addendum.

📍 FSBO Tip: Never Rely on Verbal Agreements

If a buyer wants repairs, credits, or new terms, make sure both sides sign a purchase addendum. Verbal agreements are not enforceable and do not protect you during the transaction.

Most states offer standard addendum forms, or the title company can provide one during escrow.

Looking for more real estate terms? Visit our Real Estate Dictionary.

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