Stop ordering on WhatsApp and emails.

What is a purchase order, and why does it matter?

A purchase order (PO) is a formal document a buyer sends to a seller to authorize a specific purchase. It locks in the items, quantities, prices, ship-to address, and expected delivery date — all before money or goods change hands. When the seller accepts the PO, both sides have a legally binding contract for that order. For procurement teams, small businesses buying inventory, and freelancers buying equipment, the PO is the single cleanest way to make sure what you ordered is exactly what you receive (and exactly what you're billed for).

Most disputes between buyers and suppliers come from informal orders — a phone call, a WhatsApp message, a vague email. With a written PO, you have a reference number for every conversation about that order. Invoice doesn't match? You compare it to the PO. Wrong quantity delivered? You point at the PO. Late delivery? The PO has the expected date in writing. It's the buyer's equivalent of the seller's quotation, and the two together create an unambiguous record of what was agreed.

When you should issue a PO

Any purchase above a small threshold (typically ₹5,000 or $100 — set your own) should go through a PO. Use one when:

• Buying inventory or raw materials from a regular supplier
• Ordering equipment, hardware, or software licenses for the business
• Engaging a vendor for services with defined deliverables (e.g., translation, printing)
• Procuring goods that need to be shipped to a separate address (warehouse, project site)
• Booking subcontractor work as part of a larger project you're running
• Any purchase that needs internal approval (finance team, manager sign-off)

For tiny purchases — a courier charge, a one-off office supply — skipping the PO is fine. But for anything that will appear on an expense audit, a vendor invoice, or a tax return, having a matching PO makes the paperwork bulletproof.

What to include on a purchase order

A complete PO has these fields:

1. PO number— unique reference (e.g., PO-2026-0042) used on all follow-up emails and on the supplier's invoice
2. Issue date and expected delivery date— sets the timeline. If the delivery window matters, use a date range or "on or before" phrasing
3. Buyer details — your legal entity name, billing address, GSTIN/VAT number, contact person
4. Vendor details— supplier's name, address, tax ID, contact email
5. Ship-to address — only if different from billing address (warehouse, site, branch office). This is the #1 field people forget
6. Itemized order— SKU or item code, description, unit, quantity, unit price, line total. Be specific: "A4 printer paper, 80gsm, 500-sheet ream" not just "paper"
7. Subtotal, tax breakdown, total — show CGST/SGST/IGST for India, VAT for UK/EU, sales tax for US
8. Payment terms — net 30, net 45, or advance — and currency if doing international procurement
9. Special instructions — packaging, labeling, delivery window, contact person on receipt, any quality specs

Common PO mistakes

• No PO number on the invoice.Always require the supplier to put your PO number on their invoice. Without it, your finance team can't match invoice to order and payment gets delayed.
• Vague item descriptions."Office furniture" is useless if you receive plastic chairs instead of ergonomic ones. Specify model, dimensions, color, spec sheet.
• Missing ship-to address. If your bill-to and ship-to differ, write both explicitly. Tax also depends on this: inter-state vs. intra-state for GST.
• No expected delivery date."ASAP" means different things to different people. Pick a date, even if approximate, so you can enforce it later.
• Forgetting tax treatment.For India procurement, missing the GSTIN field on the vendor side means you can't claim input tax credit. Always capture it.

PO vs. invoice — who issues what

The PO is from the buyer to the seller. The invoice flows back the other way — seller to buyer, after the goods or services are delivered. Both reference the same PO number. The buyer's accounting system marks the PO as "received" when goods arrive, and as "paid" when the invoice is settled. Need an invoice generator after receiving a vendor's goods? Use our free invoice generator to issue one to your own clients, or use this PO generator to source your inputs.