The Informal Invoice is a widely used document type in the Dutch business landscape, particularly suited for straightforward commercial transactions where a full formal invoice may be unnecessary. While maintaining a simpler format, it must still comply with the Dutch Tax Authority (Belastingdienst) requirements and include essential information such as VAT numbers, Chamber of Commerce (KvK) registration details, and clear pricing breakdowns. This document type is especially popular among ZZP'ers (self-employed professionals), small businesses, and freelancers operating in the Netherlands. The informal invoice serves as a valid proof of transaction for tax purposes and must be retained in business records according to Dutch bookkeeping requirements. Despite its informal nature, it plays a crucial role in maintaining transparent business operations and ensuring compliance with Dutch financial regulations.

1. Invoice Header: Contains invoice number, date, and document type identification

2. Seller Details: Business name, address, KvK (Chamber of Commerce) number, VAT number, and contact information of the seller

3. Buyer Details: Name, address, and relevant registration numbers (if applicable) of the buyer

4. Invoice Items: Detailed list of products/services, quantities, unit prices, and subtotals

5. Total Amount: Subtotal, VAT amount (if applicable), and total amount due

6. Payment Information: Bank account details, payment terms, and due date

7. Reference Information: Purchase order number, project reference, or other relevant identifiers