Invoicing explained
Purchase order vs Invoice
A purchase order is created by the buyer to authorize a purchase before it happens; an invoice is created by the seller to request payment after delivery. The PO commits to buy; the invoice asks to be paid.
What is purchase order?
A purchase order (PO) is sent by the buyer to the seller, listing the items, quantities, and agreed prices they want to buy. It authorizes the purchase and creates a paper trail for approval.
What is invoice?
An invoice is sent by the seller after delivering the goods or services, requesting payment. Many businesses require the matching PO number on the invoice so it can be approved quickly (PO matching).
Purchase order vs Invoice: the key differences
Here's how purchase order and invoice differ at a glance:
- Who creates it — buyer creates the PO; seller creates the invoice.
- Timing — PO before the purchase; invoice after delivery.
- Purpose — PO authorizes the buy; invoice requests payment.
How this works in Invco
Yes. Add the client's PO number to the invoice notes, which print on the PDF, so their accounts team can match the invoice to the purchase order and approve it.
Invco is invoicing software for people who run more than one company. Design your own invoice template or upload your existing invoice PDF, add line items with per-line tax and discounts, and Invco calculates the totals, numbers each invoice sequentially and emails it as a branded PDF from your own address. Every invoice is tracked from draft to sent to paid, and overdue ones are flagged automatically. Plans from $10/month.
More invoicing comparisons
- Invoice vs EstimateAn estimate is a non-binding projection of what a job will cost, sent before the work.
- Invoice vs ReceiptAn invoice requests payment for goods or services; a receipt confirms that payment has been made.
- Invoice vs QuoteA quote is a fixed price offered before the work; an invoice is the bill sent after it.
- Net 30 vs Due on ReceiptNet 30 gives the client 30 days to pay from the invoice date; due on receipt asks for payment immediately.
Frequently asked questions
What is the difference between purchase order and invoice?
A purchase order is created by the buyer to authorize a purchase before it happens; an invoice is created by the seller to request payment after delivery. The PO commits to buy; the invoice asks to be paid.
Can I put a PO number on an Invco invoice?
Yes. Add the client's PO number to the invoice notes, which print on the PDF, so their accounts team can match the invoice to the purchase order and approve it.
How much does Invco cost?
Starter is $10/month for 1 company, Growth is $20/month for up to 3 companies, Pro is $30/month for up to 8 companies, Scale is $50/month for up to 20 companies, and Unlimited is $100/month with no cap. Every plan includes every feature, with no per-invoice fees, and you get a full refund if you cancel within 7 days of a charge.
Invoice the easy way with Invco
Design your invoice template, send branded PDFs from your own email address, and see what's paid and overdue for every company. Plans from $10/month, with a full refund within 7 days.
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