Invoice types
Sales invoice
A sales invoice is the standard document a seller issues to a buyer to request payment for goods or services that have been sold.
What a sales invoice is
A sales invoice is what most people simply call an "invoice." From the seller’s point of view it records a sale and requests payment; it lists the goods or services, quantities, prices, taxes, and the total due.
It serves three jobs at once: it asks the customer to pay, it records revenue for the seller’s books, and it gives both sides a document for tax and accounting.
Sales invoice vs. purchase invoice
The same document is a "sales invoice" to the seller who issues it and a "purchase invoice" to the buyer who receives it. The label just reflects which side of the transaction you’re on.
For the seller, the sales invoice feeds accounts receivable; for the buyer, that same purchase invoice feeds accounts payable.
Example: A supplier sells $900 of parts and issues a sales invoice for $900. That document is the supplier’s sales invoice and the customer’s purchase invoice — one transaction, two labels.
FAQs
Frequently asked questions
Is a sales invoice just an invoice?
Yes. "Sales invoice" emphasizes the seller’s side — recording a sale and requesting payment — but it’s the standard invoice most businesses issue.
What’s the difference between a sales invoice and a purchase invoice?
They’re the same document seen from opposite sides: the seller calls it a sales invoice, the buyer calls it a purchase invoice.
Related terms
Invoice
An invoice is a document a seller sends to a buyer that itemizes goods or services provided and requests payment by a stated due date.
Purchase order
A purchase order (PO) is a document a buyer sends to a seller to officially authorize and commit to a purchase, listing the items, quantities, and agreed prices.
Tax invoice
A tax invoice is an invoice that separately states the tax charged on a sale (such as GST, VAT, or sales tax), so a registered buyer can claim the tax as a credit.
Put it into practice
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