What Is a Backorder? A Complete Guide for Online Sellers

What is a backorder?

A backorder is an order a customer has placed and paid for on a product you currently have zero physical stock of. Rather than removing the listing or rejecting the sale, you accept the order with the understanding — usually stated clearly on the listing or at checkout — that it will ship once new stock arrives.

Backorders are common with products that sell faster than they can be replenished: seasonal items, viral products, anything with a long supplier lead time, or stock that's genuinely in transit but hasn't been received yet. The seller is making a bet that customers will wait, in exchange for not losing the sale entirely.

Backorder vs out of stock vs pre-order — what's the difference?

These three terms get used interchangeably, but they mean different things and set different expectations with the buyer:

The practical difference that matters most: a backorder is a promise to a paying customer that has a real risk attached if your restock date slips. Getting the timing wrong doesn't just delay a sale — it breaks a commitment you already made.

When backordering makes sense

Backordering is worth doing when all of the following are true:

• You have a confirmed restock date. Stock genuinely on order with a supplier, with a real ETA — not a hopeful guess.
• The wait is short. A few days to a couple of weeks is generally tolerable to buyers. A month or more usually isn't, unless the product is scarce enough that customers are willing to wait regardless.
• You communicate it clearly. The listing, the order confirmation, and any follow-up all need to say plainly that the item is backordered and roughly when it will ship.
• The marketplace allows it. Some platforms are stricter than others about shipping delays — check the rules before relying on backorders as a strategy (more on this below).

It doesn't make sense when the restock date is genuinely unknown, when the product has already been discontinued by the supplier, or when the marketplace's late-dispatch policy makes the risk not worth it for a low-margin item.

Backorders on eBay, Amazon, Shopify and Etsy

eBay

eBay doesn't have a native "backorder" status — a listing is either available or it isn't. Sellers who backorder on eBay typically do it informally: keep the listing live, and message the buyer immediately after purchase to explain the delay. This is risky. If dispatch takes longer than your stated handling time, it counts against your late-dispatch rate and can trigger a defect if the buyer opens a case. If you're going to backorder on eBay, update your handling time on the listing to reflect the real wait, not the normal one.

Amazon

Amazon is stricter still. Selling an item you can't ship within your stated handling time risks an Order Defect Rate hit and can affect account health, particularly if it happens repeatedly. Amazon doesn't offer a formal backorder mechanism for third-party sellers the way it does for its own retail inventory — most sellers either extend handling time temporarily or take the listing down until stock arrives, rather than risking the metric.

Shopify

Shopify is the most backorder-friendly of the major platforms. You can leave "Continue selling when out of stock" enabled on a variant, and pair it with a note on the product page ("Ships in 2 weeks" or similar). This is a genuine, supported backorder flow — as long as you're transparent about the delay on the page itself.

Etsy

Etsy expects processing times set at the listing level to reflect reality. If you're backordering, update the listing's processing time to cover the real wait rather than leaving it at your normal turnaround — Etsy's policies around late shipping apply the same way they would to any other order.

How to manage backorders without it turning into chaos

• Track backordered quantity separately from available quantity. If you have 20 units on order but zero physical stock, your system needs to know the difference between "0 available now" and "20 committed to arrive." Selling further backorders past your incoming quantity is how you end up unable to fulfil orders you've already accepted.
• Set a hard cutoff. Decide in advance how many backorders you'll accept before pulling the listing — don't let it run unbounded on a hope that the next shipment covers everyone.
• Communicate proactively, not just at checkout. If the restock date slips, tell backordered customers before they ask. A slipping ETA with no warning is what turns a patient buyer into a refund request.
• Fulfil backorders in order. First paid, first shipped when stock lands — anything else creates support tickets.

How accidental backorders happen — and how to stop them

Most backorders aren't a deliberate strategy — they're an accident. A listing stays live after the real stock count hits zero because the seller's inventory tool updates on a delay, or because stock is tracked separately per channel and one of them simply doesn't know a sale happened elsewhere. The customer buys an item that's already gone, and the seller only finds out when they go to pack the order.

This is the same root problem behind overselling: stock isn't syncing in real time across every channel you sell on. The fix is the same either way — a central stock count that updates the moment a sale happens anywhere, so a listing goes to zero everywhere within seconds, not minutes or hours later. That's what turns a genuine backorder decision into something you chose, rather than something that happened to you.