Which item identifies a specific sales transaction on an invoice?

• A. Invoice date
• B. Invoice number
• C. Net amount
• D. VAT amount

Answer: (B)

In bookkeeping, you need a unique reference to pick out exactly which sale a document refers to. The item that serves this purpose on an invoice is the invoice number—the unique identifier assigned to that specific sale. It lets you distinguish this sale from every other sale, and it’s the reference you use to match payments and files.

The date shows when the sale happened, but several invoices can share the same date, so the date doesn’t uniquely identify a single transaction. The net amount is the total before tax, and the VAT amount is the tax portion; neither uniquely identifies which sale it is.