Shopify's "continue selling when out of stock": what it does and its limits

Shopify’s “Continue selling when out of stock” is the setting most merchants find when they want to keep selling a product that’s hit zero. It works — the variant stays buyable past zero instead of showing “Sold out” — but it does only that. There’s no pre-order label, no ship-date, and no automatic switch-back when stock returns, so on its own it just oversells silently. Here’s exactly what it does, the three limits that bite, and how to turn it into a proper pre-order.

What does “continue selling when out of stock” do?

It lets a single variant keep accepting orders after its inventory reaches zero. Instead of the storefront showing “Sold out,” the normal “Add to cart” stays live and shoppers can keep buying. That’s the whole feature — it’s an inventory override, not a pre-order system.

Where is the setting?

On the product page, in each variant’s Inventory section, under “When out of stock”, choose “Continue selling.” It’s set per variant, so a product with ten variants means ten checkboxes — and ten to undo later.

What are the limits?

Three gaps catch merchants out, and all three cost money or trust:

1. No pre-order signal to the shopper. The button still says “Add to cart” with no “Pre-order” label and no expected-ship date, so a backordered item looks exactly like an in-stock one. Shoppers expect it now, and a surprise wait drives support tickets and chargebacks.
2. It never switches itself back. When stock returns, “Continue selling” stays on until you manually turn it off — so popular products quietly keep overselling for days after they’re restocked.
3. It’s per variant, by hand. Turning it on (and off) one variant at a time across a catalog is tedious and easy to get wrong — which is how a product ends up half overselling.

How do you turn it into a real pre-order?

Keep the “sell past zero” behaviour, but add the three things the native checkbox is missing: a clear “Pre-order” button with expected-ship messaging, and — the important part — an automatic, reversible switch-back so the product returns to normal selling the moment stock lands.

A pre-order app does this per product in one click: it flips every variant to keep selling, swaps the storefront button to “Pre-order,” and records each variant’s exact prior inventory policy so that when you turn pre-orders off (or stock returns), every variant is restored precisely — no products left silently overselling. If you’d rather not take money for stock you can’t ship yet, the alternative is to capture interested shoppers and email them on restock instead — see back-in-stock vs pre-order for when each fits. (Setup walkthrough: how to set up pre-orders on Shopify.)

Do it cleanly with Prestock

Prestock turns “continue selling” into a real pre-order: one click per product flips every variant to keep selling, swaps the button to a clear “Pre-order” with ship-date messaging, and restores each variant’s exact prior inventory policy the moment you turn it off — so nothing is left overselling. There’s a free plan to try it on a single product, and Pro adds scheduled launches and auto-toggle on restock. It’s the difference between a checkbox that quietly oversells and a pre-order that sells the sold-out product and cleans up after itself.