Inventory how-to

How to number purchase orders

Use a short prefix plus a sequential number, like PO-1001, and increase by one each time.

Short answer: Use a short prefix plus a sequential number, like PO-1001, and increase by one each time. Keep the sequence in one place so you never reuse a number, and let your system assign it automatically when a purchase order is created.

Why numbering matters

Purchase order numbers let you match invoices, packing slips, and payments to the right order. If two orders share a number, or numbers get skipped and reused, your supplier and your bookkeeping both get confused.

Pick a simple format

A prefix plus a running number works for almost any store. For example PO-1001, PO-1002, PO-1003. You do not need the supplier name, date, or SKU count in the number itself. Keep extra detail like supplier and date in the order record, not jammed into the number.

Keep the sequence in one system

If you create purchase orders in more than one place (spreadsheet, email, an app), the sequence breaks. Pick one system as the source of truth for numbering and have every order pass through it, even ones you place by phone or in person. Write those down manually using the next number in sequence.

Handle cancellations and edits

If you cancel a purchase order, do not reuse its number. Mark it cancelled and move on. If you need to change quantities after sending it to a supplier, create a new numbered order or a clearly marked revision rather than editing the original silently.

Step by step

  1. Choose a prefix, such as PO or your store initials
  2. Start a running count, for example at 1000
  3. Assign the next number automatically or manually for every order, no exceptions
  4. Never reuse a number, even for cancelled orders
  5. Record supplier, date, and SKUs in the order details, not the number
  6. If you place orders outside your main system, log them into the same sequence by hand
  7. Review the list periodically for gaps or duplicates

Worked example

Say your last purchase order was PO-1042 to a mug supplier. Your next order, to a packaging supplier, becomes PO-1043, regardless of which supplier it goes to. Three days later that packaging order gets cancelled before shipping. You do not reuse PO-1043. Your next real order, to a third supplier, is PO-1044.

How SteadyShelf helps

SteadyShelf drafts purchase orders and numbers them automatically when it creates them, so you do not have to track a sequence by hand for anything generated through the app. If you also place orders outside SteadyShelf, by phone or email directly, you will need to log those into the same numbering by hand to keep one consistent sequence.

$29/month flat, unlimited products and suppliers, 30-day free trial. Run the numbers now with the free reorder point calculator.

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FAQ

Should purchase order numbers include the supplier's name?

You can, but it is not necessary and makes the sequence harder to follow at a glance. It is simpler to keep the number plain, like PO-1001, and store the supplier name as a separate field on the order.

What if I already have duplicate purchase order numbers in my records?

Go through your past orders and relabel the duplicates with new numbers at the end of your current sequence, noting the old number in each order's details so invoices still match up. Going forward, make sure only one system assigns new numbers.

Let SteadyShelf do this math for every SKU

Order-by dates per supplier, seasonal forecasts and draft POs for your Shopify store. $29/month after a 30-day free trial.

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