Ensure you have the setup as outlined in the Chart of Accounts section in Getting Started with Advanced Prepayments.

Example Scenario

  1. Create a new Sale or Purchase.
  2. Add some items.
  3. Set a quantity for each item.
  4. Set the Prepayment % or Prepayment Amount on the Header.
  5. Change the GST Prod. Posting Group on the lines.
  6. Post the Prepayment – Next to Order > Show More > Actions > Posting > Prepayment > Post Prepayment Invoice…

To review the result

  1. Go to Related > Prepayment > Prepayment Invoices.
  2. Select the Prepayment Invoice you just created in the Example Scenario section.
  3. Print/Send > Print.
  4. Preview.
  5. The VAT/GST % column will match the VAT/GST Prod. Posting Groups you set in the Example Scenario above.