The second copy is the invoice copy (for the buyer's bookkeeping), the third copy is the deduction copy (for the buyer's tax deduction certificate), the fourth copy is the bookkeeping copy (for the seller's bookkeeping), and the seventh copy is the backup copy, which is used for enterprise card issuing, inspection and warehouse retention respectively; Ordinary invoices are only in triplicate, with the first stub, the second invoice and the third bookkeeping.

The contents of the invoice are different: the special VAT invoice includes the taxpayer's tax registration number, the amount excluding VAT, the applicable tax rate and the VAT payable. In addition to the contents of ordinary invoices such as the name of the buyer, the seller, the goods or services, the quantity and measurement unit of the goods or services, the unit price and total price, the billing unit, the payee and the billing date.

There are two kinds of invoices (official tax receipts): four copies and seven copies (excluding stub invoices). The first copy is stub invoices (official tax receipts).