Inventory glossary

What is Purchase order number?

Purchase order number is the unique ID assigned to a purchase order so the store, the supplier, and the receiving process can all refer to the same order without confusion.

A purchase order number keeps your buying organized once you have more than a handful of orders running at once. Without one, you end up matching invoices and shipments to orders by guessing, which gets messy when a supplier sends part of an order now and the rest later.

Use a consistent numbering pattern, like a running count or a date plus a sequence, so you can sort and search your orders easily. Put the number on the order itself, on any emails to the supplier, and reference it when you receive stock, so every box and invoice ties back to the right order.

Example

A candle store numbers its orders PO-2024-001, PO-2024-002, and so on. PO-2024-014 is sent to a wax supplier for 200 units. When half the order arrives three weeks later, the packing slip references PO-2024-014, so the owner knows exactly which order it is and how many units are still outstanding.

Common mistakes

  • Reusing numbers or restarting the sequence partway through the year, which causes duplicates.
  • Not including the PO number on supplier emails or invoices, making it hard to match payments and shipments later.
  • Using different numbering systems across suppliers or staff, which breaks any attempt to track orders in one place.

Purchase order number and SteadyShelf

SteadyShelf assigns a purchase order number to each draft PO it creates, so when it is emailed to the supplier and stock is later received against it, everything stays matched to the right order.

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Related terms

Purchase order · Receiving · Partial receipt · Supplier · Three-way match

Full inventory glossary

FAQ

Why does a small store need purchase order numbers?

Once you place more than a few orders, you need a way to tell them apart. A PO number lets you match invoices, shipments, and partial deliveries back to the right order instead of guessing from memory or email threads.

What is a good way to number purchase orders?

A simple running sequence, like PO-001, PO-002, or a date-based format like PO-2024-01, works well. The key is staying consistent so numbers never repeat and you can sort orders chronologically.

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