What Is a Purchase Invoice?

What information is on a purchase invoice?

A purchase invoice normally carries the supplier’s invoice number and issue date, the legal or trading identities of both parties, item descriptions, quantities, prices, discounts, tax, currency, total, due date, and payment instructions. Required fields depend on the location and transaction.

The buyer should preserve the supplier’s original number rather than replacing it with an internal invoice number. An internal document ID can be added separately so the source invoice remains traceable.

• Supplier invoice number and dates
• Supplier and buyer details
• Items, quantities, prices, tax, and total
• PO reference, due date, and payment terms

Purchase invoice vs purchase order

The buyer creates a purchase order before supply to authorize what may be bought. The supplier creates the invoice after the agreed billing event to request payment. The buyer then receives and records that document as a purchase invoice.

A PO does not prove delivery or payment, and a purchase invoice does not prove authorization. Comparing the invoice with the approved PO and receipt or service approval helps identify price, quantity, duplicate, or supplier differences.

• PO is created by the buyer
• Invoice is created by the supplier
• Purchase invoice is the buyer’s incoming-invoice record
• Receipt or approval confirms supply

Purchase invoice vs sales invoice

The names describe the same transaction from opposite sides. For the supplier, the document is a sales invoice because it records a sale and amount receivable. For the buyer, it is a purchase invoice because it records a purchase and amount payable.

The PDF does not need two labels. It is normally titled Invoice. The accounting system determines whether the document is entered in sales or purchases based on whether the business issued or received it.

• Supplier: sales invoice and receivable
• Buyer: purchase invoice and payable
• One source document, two accounting perspectives
• A receipt is separate proof of payment

How should a buyer process a purchase invoice?

Confirm the supplier, invoice number, dates, tax treatment, currency, bank details, and arithmetic. Match the invoice to the approved purchase order and evidence of delivery or service approval when those controls apply. Resolve exceptions before payment rather than editing the supplier’s document.

Record the approved amount and due date, schedule payment through the authorized process, and link the payment reference back to the invoice. Retain the original invoice, approvals, corrections, credits, and payment record for the period required by applicable accounting and tax rules.

• Check identity, references, and totals
• Match authorization and receipt evidence
• Resolve differences before payment
• Link approval, payment, and retention records

Read it from the buyer’s side

The supplier calls it a sales invoice; you may call it a purchase invoice or supplier bill. It describes an amount the supplier is charging your business. The same document should not be entered twice merely because different people use different names.

Check the supplier, invoice reference, date, currency, goods or services and payment terms. If the purchase belongs to a particular project or department, record that connection so you can understand the cost later.

Verify the supplier and payment details

Compare the invoice with the supplier you actually engaged. An unexpected change of bank details deserves confirmation through a known contact method, rather than relying only on the new details printed on the invoice or in an unsolicited email.

This is particularly important when a genuine supplier’s name appears on a document with unfamiliar payment instructions. Keep the confirmation record with the invoice where appropriate, and use your business’s agreed approval process before transferring money.

Match the invoice to the purchase and receipt

Compare the order, evidence of goods or services received and the invoice. If you ordered ten units, received eight and were billed for ten, establish whether the rest are still coming or the invoice needs correction.

For service purchases, confirm the billed period or milestone with the person who accepted the work. A purchase order alone shows authorization; it does not always prove that the supplier completed the service being charged.

Keep approval and payment as separate statuses

An invoice may be received, under review, approved, scheduled or paid. These are different events. Marking it paid when it is merely approved can hide an outstanding obligation, while paying a document already settled creates another problem.

Record who approved it, the planned payment date and the actual payment reference. If a single transfer covers several supplier invoices, allocate the amounts clearly so each balance can be checked.

Give the cost a useful category

The purchase could be inventory, a project cost, an operating expense or an asset, depending on the facts and applicable accounting rules. The invoice provides evidence, but its title does not determine the correct accounting or tax treatment.

Keep descriptions, business purpose and supporting information. If you are unsure whether equipment should be treated as a current expense or an asset, preserve the purchase facts and ask the person responsible for the accounts rather than choosing a category solely to clear the inbox.

Record credits and refunds against the original purchase

A return, discount correction or service adjustment may lead to a credit note or refund. Connect it to the original invoice and update the amount payable. Do not leave the original total waiting for payment after a credit has reduced it.

When the supplier sends a statement, reconcile its invoice and credit references to your records. The statement summarizes the account; entering its total as a new purchase can duplicate costs already recorded.