A proforma invoice is not a true invoice – it is simply a document that declares the seller’s commitment to provide the goods or services specified to the buyer at certain prices.
Proforma invoices are not recorded as an accounts receivable by the seller nor are they recorded as an accounts payable by the buyer.
When proforma invoices are used
If you need to issue a sales document for goods or services you haven't supplied yet, you can issue a proforma invoice to offer goods or services to customers.
Proforma invoices are also often used to declare the value of goods for customs.