How to Create a Purchase Order — Step-by-Step Guide

What Is a Purchase Order — and Why Does It Matter?

A purchase order (PO) is a formal, legally binding document that a buyer sends to a supplier to authorise a purchase. Once the vendor accepts it, the PO becomes a contract: both parties are committed to the agreed quantity, price, delivery date, and payment terms. The supplier is obligated to deliver; the buyer is obligated to pay.

Without a PO, you are buying on trust. A PO protects both parties: it gives the supplier written confirmation that the order is real, and it gives the buyer documented proof of exactly what was ordered — so there can be no dispute when the goods arrive or the invoice lands.

Any B2B procurement of goods or services — from ordering raw materials to engaging a contractor — benefits from a PO. Many large corporations will not even begin fulfilling an order until they have a PO number from the buyer.

Step 1: Fill in the PO Number and Date

Every PO needs a unique purchase order number. This number follows the transaction through its entire lifecycle — from approval, to goods receipt, to invoice matching, to payment. Without it, finance and operations teams cannot link documents together.

Use a consistent numbering format: a prefix, year, and sequence number works well (e.g., PO-2025-0042). Never reuse a PO number. The date should reflect when the PO is raised, not when the goods are expected.

Step 2: Enter Vendor Details

The vendor section identifies who you are buying from. Include:

• Vendor name and legal entity — use the exact registered name, not a trading abbreviation.
• Vendor address — the registered or billing address of the supplier.
• Contact name — the sales rep or account manager handling your order.
• Vendor GST/VAT number — required for tax compliance in most jurisdictions.

Accurate vendor details matter because the PO is the document your accounts payable team will match against the incoming invoice. If names or tax IDs differ, payment can be held up.

Step 3: Add Your Billing Address

Your billing address (the buyer's address) tells the vendor where to send the invoice. For GST-registered businesses in India, this must match the address on your GST registration, as the vendor will use it to raise a tax invoice.

Step 4: Specify the Delivery Address and Required Date

The delivery address may differ from your billing address — for example, goods ordered centrally but delivered to a specific warehouse or job site. Confirm the exact address, including any loading dock or contact person at the delivery point.

The required delivery date is not a suggestion. It sets a contractual deadline. If your production schedule depends on the delivery, state that explicitly in the special instructions (see Step 7). Vendors use this date to plan logistics; a clear date prevents vague commitments.

Step 5: List the Line Items

This is the core of the PO. For each item or service, include:

• Item description — be specific. "Office chairs, ergonomic, model X200" is better than "furniture."
• Quantity — in units the vendor understands (pieces, kg, litres, hours).
• Unit price — the agreed price per unit, excluding tax.
• Line total — quantity multiplied by unit price.
• HSN/SAC code — required for GST invoices in India; identifies the goods or service category for tax purposes.

The line item total forms the subtotal of the PO. Taxes (GST, VAT) are then calculated on this subtotal and shown separately, giving the final order value. Any price agreed verbally should be confirmed in writing here — discrepancies between the PO unit price and the vendor's invoice unit price are a common source of disputes.

Step 6: State Payment Terms

Payment terms define when you will pay and under what conditions. Common terms include:

• Net 30 — payment due within 30 days of the invoice date.
• Net 15 / Net 7 — faster payment, often in exchange for a small discount.
• 50% advance, 50% on delivery — common for custom or made-to-order goods.
• Payment on delivery — goods handed over only when payment is confirmed.

State terms precisely. "30 days" is ambiguous — from order date? Invoice date? Receipt of goods? "Net 30 from invoice date" removes all ambiguity. Both your accounts payable team and the vendor's accounts receivable team need clarity here.

Step 7: Add Special Instructions

The special instructions (or notes) field captures anything that does not fit the standard fields:

• Packaging requirements (e.g., palletised, shrink-wrapped, labelled with batch numbers).
• Delivery window restrictions (e.g., delivery only between 9 am and 4 pm).
• Quality standards or certifications required.
• Reference to the original quote or tender document.
• Penalty clauses for late delivery (if applicable).

Do not leave this field blank if you have specific expectations. Anything not on the PO is difficult to enforce later.

Step 8: Get It Authorised and Send It

Most organisations require a PO to be approved before it is sent to the vendor. Depending on order value, this may require sign-off from a department manager, finance, or a director. The authorisation serves as an internal control: it confirms the spend is approved and budgeted.

Once authorised, send the PO to the vendor — typically by email as a PDF. Ask the vendor to confirm receipt and acceptance. Their confirmation email (or a signed copy of the PO) completes the contract. Keep this confirmation on file.

What the Vendor Does with Your PO

On the vendor's side, the PO triggers their fulfilment process: picking, packing, manufacturing, or scheduling the service. The PO number becomes a reference on their sales order, despatch note, and — crucially — the invoice they raise against you. When their invoice arrives, your finance team will match the invoice PO number against your internal PO record to confirm the order was legitimate.

The Three-Way Match: PO, Delivery Note, and Invoice

When goods arrive, your receiving team should check them against the PO and the vendor's delivery note (or packing list). This is the start of the three-way match — one of the most important controls in procurement:

• PO — what you ordered, at what price, in what quantity.
• Delivery note / goods receipt note (GRN) — what was actually delivered.
• Vendor invoice — what the vendor is charging you for.

All three must agree before payment is released. If the invoice quantity differs from the delivery note, or the invoice price differs from the PO, the discrepancy must be resolved first. This process prevents overpayment, fraud, and billing for goods not received. It is the reason a PO number must appear on every vendor invoice — without it, the match cannot happen.

Common Mistakes to Avoid

• No PO number on the invoice: Always instruct vendors to quote your PO number on their invoice. Without it, payment can be delayed indefinitely in large organisations.
• Vague line item descriptions: Vague descriptions lead to disputes about whether the delivered goods match what was ordered.
• Missing delivery date: Without a stated date, you have no contractual basis for complaining about late delivery.
• Unsigned or unapproved POs: A PO without an authorised signature is not a binding commitment in many jurisdictions.
• Raising a PO after the goods have already arrived: A retroactive PO defeats the purpose of procurement control. Raise the PO before the order is placed.