Stockout vs. Backorder

A customer hits a sold-out product page. Whether that's a stockout or a backorder isn't about how it looks on the page — it's about whether they can still place the order.

Definitions

A stockout is demand that can't be met right now because inventory is depleted. It's a state, not a decision — the moment available stock hits zero, every unit of demand that arrives from then until restock is, by definition, a stockout.

A backorder is what happens next, and it's a choice, not a state. Instead of turning that demand away, you hold it and fill it once the next normal delivery replenishes the inventory. The customer still gets the product; they just wait for it.

The alternative to backordering is what the underlying research literature calls "no backlogging" — a lost sale. Excess demand over available stock either gets met by a priority shipment arranged specifically for it, or it isn't met at all, and the order is cancelled or the customer leaves. Shopify's own "Continue selling when out of stock" setting is the practical, admin-level version of choosing to backorder rather than lose the sale outright — turning it on lets checkout continue past zero available inventory instead of blocking it.

Why they're confused

From the shelf's point of view, a stockout and a backorder look identical: zero units available right now. That's exactly why the two terms get used interchangeably in casual conversation, and why it matters to separate them precisely. The stock level tells you almost nothing about what the customer sees. Two products can hit zero available inventory on the same day and end up in completely different places — one shows a dead "sold out" page, the other keeps taking orders against a promised restock date. The stock event is identical; the customer experience is a policy decision made separately from it.

When each applies

Backordering works when the customer is willing to wait and the product will genuinely arrive as promised — a restockable, non-perishable item where a delay is a recoverable inconvenience, not a different kind of loss. It works less well for a seasonal or trend-driven item: a customer who backorders a product that arrives after the trend, the season, or their own patience has passed hasn't really been "saved" from a stockout — they've just been given a slower way to abandon the order.

That's a genuinely different planning problem than the reorder-point math the rest of this site covers, and it's worth knowing which situation you're actually in before deciding whether to offer a backorder at all, rather than defaulting to "always" or "never" for every product in the catalog.

Whether a specific stockout should become a backorder, get hidden, or stay listed with a waitlist is a per-product decision with its own tradeoffs — what to actually do when a Shopify product goes out of stock walks through it. Preventing the stockout in the first place, so this decision comes up less often, is covered in how to prevent stockouts on Shopify.

Frequently Asked Questions

What's the difference between a stockout and a backorder?

A stockout is a state: available inventory has hit zero, and demand that arrives now cannot be met from stock. A backorder is a policy choice you make in response to that state — the customer can still place an order, and it's held until new stock arrives, rather than being turned away entirely.

Is a backorder a type of stockout?

Yes, in the sense that it starts from the same zero-stock condition. The distinction is what happens next: a plain stockout with no backorder option turns away demand outright (a lost sale, or a priority shipment if you arrange one); a backorder holds that demand and fills it once the next shipment lands.

Does offering a backorder count as being "in stock" for SEO purposes?

That depends on how your theme and any backorder app label the product page, not on the terminology itself. A page that stays live and orderable with a clear restock date behaves differently in search and for the shopper than one that shows a hard "sold out" state — see what to actually do when a product goes out of stock for the tradeoffs.

Knowing a SKU is about to hit this line matters more than sorting out the terminology after the fact — that's what StockCue's reorder alerts are built to catch, on every plan including Free, before the stockout-or-backorder decision is even on the table.