How a backorder works
The customer buys, pays or commits, and the shop promises to ship once the incoming consignment lands. The order sits in a queue attached to a purchase order rather than to stock on hand, and it releases automatically when the goods are received. Some shops take full payment up front, some take a deposit, and some authorise the card and only charge at dispatch.
Two things have to be true for it to work. The shop must know when the supply is genuinely arriving, and the customer must be told plainly that this is what they are agreeing to, on the product page and again in the confirmation. A backorder that reads like a normal purchase is not a backorder — it is a surprise waiting to be discovered.
Why backorders matter
They convert demand you have already paid to attract. When a campaign is running and an item empties, the alternative to a backorder is usually a lost sale plus a customer who has now found a competitor. Taking the order keeps the relationship and gives you a real signal of how much of the incoming shipment is already spoken for.
They also change what your data means. Revenue recorded at the moment of order is not revenue you have earned until the item ships, so a period with many backorders can look stronger than it is. Anyone reading the numbers to judge campaign performance needs to know which orders are still waiting on stock.
Where backorders go wrong
Vague promises cause most of the damage. Wording like “shipping soon” invites the customer to invent their own timeline and be disappointed by it. Repeated slippage is worse still: each new date the shop misses costs more goodwill than the original delay, and support time rises faster than the order value justifies.
The other common error is taking backorders on the wrong products. Low-value, easily substituted items are not worth waiting for, and the cancellations and refunds that follow can cost more than the margin. Advertising an item you cannot ship for a long period also puts the feed and the landing page out of step, which the ad platforms treat as an availability problem.
Getting it right
Use the correct availability value in the feed instead of leaving the item marked as in stock, and mirror that on the page: state that it is on backorder, give the date you are actually confident about, and confirm it again by email. Where payment is taken up front, make the refund terms visible before checkout, not afterwards.
Limit backorders to items with a known, short lead time and enough margin to survive a cancellation. Everything else is better served by a notify-me form, which captures the same interest without a promise attached. Treat the queue as a marketing asset too: a list of people who wanted the item enough to wait is one of the better email marketing audiences you will ever build, and it is worth watching how backorders affect your refund rate.