July 24, 2026 · 5 min read

How to track purchase order margin in Shopify

Unit cost tells you what you're paying. It doesn't tell you whether the order is actually worth placing. A supplier can offer a lower unit cost that still produces a worse margin than a slightly pricier one — you can't see that from a cost column alone.

Margin is the number that actually drives the buying decision, and it needs to be visible at the point where you're deciding what to order, not after the fact in a spreadsheet.

Why line-by-line matters, not just a PO total

A single purchase order often mixes items with very different margins — a loss-leader accessory next to a high-margin core product. A total-only view hides that: it can tell you the order looks fine overall while one line inside it is actually losing money at the price you're planning to sell it.

Seeing margin per line means you catch a mispriced item — a typo in the unit cost, a supplier price increase you didn't clock, a selling price that hasn't kept up with cost — before the stock is on the shelf, not after.

How margin tracking works in Reorda

Every purchase order line in Reorda has both a unit cost (what you're paying the supplier) and a selling price (what you plan to sell it for):

• Selling price auto-fills from the product's current live price in Shopify the moment you add it to a draft PO — no need to look it up separately or copy it in by hand.
• Both fields stay editable while the PO is a draft, so you can model a cost negotiation or a planned price change before committing to the order.
• Margin per line — (selling price − unit cost) ÷ selling price — updates live as you adjust either number.
• Blended margin for the whole PO sits in the footer: total cost, total retail value, and the overall margin percentage across every line, weighted by quantity.

None of this touches your live Shopify product price. It's a planning layer on top of the purchase order — the numbers you use to decide whether the order makes sense, kept separate from what's actually listed in your store.

A worked example

Say a draft PO has two lines: 150 units of a snowboard at $600 unit cost and a $2,629.95 selling price (77.2% margin), and 12 units of a second snowboard at $80 unit cost and $800 selling price (90% margin). The footer shows a combined cost of roughly $90,960 against a retail value of about $404,492 — a blended margin in the high 70s. If you then negotiate the first line's unit cost down, the blended number recalculates instantly, so you can see exactly how much a cost change moves the whole order's profitability before you mark it as ordered.

Once the order's placed, the next step is getting it into your store — see how receiving purchase orders into Shopify inventory works, or read up on calculating a reorder point so the next order gets placed automatically before you run out.