Backorders and stockouts both cost Amazon brands revenue and rank, but for different reasons. This guide breaks down why each one happens, the steps that keep your inventory ahead of demand, and how to recover fast if a stockout already impacts your rankings.
A backorder happens when a customer orders a product that’s temporarily unavailable but has a confirmed restock date. You accept the order today and fulfill it the moment new inventory lands.
The term comes from “backlog,” the pile of unfilled orders that builds when demand outpaces supply. Whether the cause is a surprise sales surge, a supplier delay, or a forecasting miss, a backorder lets you keep capturing revenue instead of turning shoppers away with nothing.
Ecommerce sellers often use “backorder” and “out of stock” interchangeably, but they don’t mean the same thing. This distinction has important implications for inventory planning, customer communication, and overall operational strategy.
Three backorder types show up most often:
Identifying which type you’re dealing with is the first step, as it determines both the urgency of your response and how you should communicate with customers.
The difference between a backorder and an out-of-stock item comes down to two questions:
Can customers still place orders, and do you know when the inventory will be available again?
With a backorder, the product remains available for purchase, and customers receive an estimated ship date, allowing demand to be captured while inventory is replenished.
An out-of-stock product is typically removed from sale entirely, with no confirmed restock date. Unlike a backorder, this immediately halts sales and can negatively impact organic rankings, product visibility, and future revenue.
Amazon does not support true backorders in the same way as a direct-to-consumer (DTC) ecommerce website. Under Fulfillment by Amazon (FBA), a listing generally becomes unavailable once your inventory reaches zero, though the status can vary depending on whether inventory is reserved or processing. Under Fulfilled by Merchant (FBM), you can extend your handling time or set a future restock date in Seller Central to approximate a backorder, but Amazon treats this as a workaround rather than a built-in feature.
Inaccurate demand forecasting is one of the most common causes of backorders and stockouts. Sales accelerate faster than expected while the next replenishment shipment is still weeks away. Even well-managed brands can be caught off guard when a viral post, media mention, or sudden improvement in search rankings triggers an unexpected surge in demand.
Supplier delays are another major risk. Manufacturing slowdowns, port congestion, customs holds, and material shortages can extend lead times with little warning. If your reorder point does not include enough buffer, even a minor delay can create a gap between selling out and restocking. Working with multiple qualified suppliers and using conservative lead-time estimates can reduce that risk.
External demand spikes cause the hardest-to-predict stockouts: Prime Day, competitor stockouts, or a seasonal surge. Amazon’s Restock Inventory tool uses sales history, demand forecasts, seasonality, and replenishment settings to estimate future inventory needs. However, recommendations are only generated for SKUs with sufficient recent sales and projected demand, making the tool less reliable for newer ASINs or highly seasonal products. Relying on these recommendations alone can increase the risk of stockouts during periods of peak demand.
Best Seller Rank reflects recent sales performance, so when inventory runs out and sales stop, BSR and category visibility can decline. Stockouts can also weaken organic keyword rankings because the listing is no longer generating the sales and engagement signals that supported those positions.
Sponsored Products and Sponsored Display ads are typically retail-aware and stop serving when the item is unavailable, After restocking, ranking recovery can take anywhere from several days to a few weeks, depending on how long the stockout lasted and how competitive the keyword is. Many sellers increase PPC and promotional activity after restocking to rebuild traffic and sales velocity.
Worried your current inventory gaps are quietly hurting rankings and revenue? Luminize will help your business uncover stockout risks before they cost your brand more sales. Request a free audit to get started.
For brands weighing FBA vs. FBM, the choice of selling model directly affects how much flexibility you have when inventory gaps occur.
Fulfillment by Amazon (FBA) sellers do not have a native backorder option. Once FBA inventory reaches zero, the offer generally becomes unavailable, though in some cases customers can still place orders while inbound inventory is on the way to Amazon but has not yet been received and made available. That makes proactive inventory management essential for FBA brands, because there is no true safety net once sellable stock runs out.
Fulfilled by Merchant (FBM) sellers have more flexibility than FBA sellers. In Seller Central’s “Manage All Inventory” section, you can sometimes set a future restock date or adjust handling time to cover a short inventory gap while stock is in transit, depending on your marketplace and offer settings. Once inventory reaches zero, however, the offer may become unavailable or inactive, so FBM is more flexible than FBA but still not a true substitute for running out of stock. .
Many brands use an FBA/FBM hybrid as a practical risk-management strategy.
A common setup is to run the main offer through FBA for Prime eligibility, while also keeping a separate FBM offer live on the same ASIN with a different SKU. If FBA inventory runs out or inbound stock is delayed, the FBM offer can help preserve sales opportunities and reduce disruption to sales momentum.
Amazon allows both fulfillment methods on the same ASIN, using separate SKUs. The FBA/FBM hybrid is often used as a backup during stockouts or fulfillment disruptions, and it can help preserve sales opportunities when FBA inventory runs low. Its effectiveness still depends on Buy Box ownership, pricing, shipping speed, and conversion performance.
Pull at least 12 months of sales history and account for seasonality, promotions, and growth trends. Amazon’s built-in forecasting tools provide a useful starting point, but accurate inventory planning requires a deeper analysis of sales velocity, demand patterns, advertising impact, and market conditions.
Your reorder point formula is: (average daily sales × supplier lead time) + safety stock.
Safety stock formula is is: (maximum daily sales × maximum lead time) minus (average daily sales × average lead time).
Many sellers underestimate lead times and demand variability, resulting in inventory gaps and missed sales opportunities. These calculations should be reviewed at least quarterly to reflect changing demand patterns, supplier performance, and business growth.**
Relying on a single supplier creates a major point of failure. Qualify at least two suppliers for top-performing Stock Keeping Units (SKUs), and consider using a third-party logistics (3PL) provider to store buffer inventory closer to Amazon’s fulfillment network. This enables faster replenishment and reduces reliance on direct overseas shipments.
Amazon Warehousing & Distribution (AWD) sits upstream of FBA and can automatically replenish fulfillment centers from bulk inventory as stock sells through. Many high-volume brands use a two-layer buffer, keeping larger reserves in AWD and a smaller working supply in FBA, with the exact split depending on velocity, lead times, and replenishment risk.
Keep a small reserve for your top ASINs with your 3PL specifically for backup FBM listings. FBM won’t convert as Prime does, but it keeps your ASIN active and your rank from collapsing while FBA restocks.
Your IPI score, on a scale of 0 to 1,000, measures how efficiently you manage FBA inventory over time. Amazon uses IPI along with other factors to determine storage capacity, and sellers commonly treat 400 as the practical minimum threshold in 2026. The score is influenced by excess inventory, sell-through, stranded inventory, and in-stock rate, so a low IPI can reduce storage capacity and make replenishment harder. A practical way to manage it is to keep inventory balanced, fix stranded units quickly, and use promotions or advertising to move slow stock before it becomes excess inventory.
Start recovery as soon as your inventory is back. The longer you wait, the harder it becomes to rebuild lost visibility.
Reactivate Sponsored Products campaigns immediately, focusing on the exact and phrase match keywords that performed best before the stockout. Increase bids gradually over several days and prioritize the terms with the strongest conversion history.
Coupons and limited-time promotions can also help accelerate recovery. “A 10%–15% discount can improve conversion rates, and many brands use that range for conversion-focused offers because it often creates action without giving away too much margin.” Use Sponsored Display or Amazon DSP to retarget shoppers who viewed your products before the stockout. These warmer audiences may convert more quickly than new visitors.
Rankings may begin improving within 7 to 14 days after restock, but full recovery can take longer after an extended stockout. If rankings are not recovering, the issue is usually not one single factor; it’s often a combination of low sales velocity, weak conversion, or competitive pressure that needs to be addressed in stages.
Inventory gaps are a preventable source of lost Amazon revenue, which is why Luminize builds forecasting, replenishment, and inventory visibility into every partnership model.
Its proprietary Overwatch platform gives brands real-time visibility into revenue, risk, and performance, bringing the data needed to catch stockout risks before they hit rankings or sales velocity.
For brands that want the most integrated approach, the Retail Partnership model goes further: Luminize purchases inventory directly and sells through its own established Amazon account, aligning both sides around the same outcome: product always in stock, rankings protected, and long-term performance maintained without agency fees.
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Backorders can strain customer trust when restock dates change or communication falls behind. They may also increase cancellations, customer service requests, and fulfillment pressure. On Amazon, backorders are limited to merchant-fulfilled products that can ship within 30 days. Missing the promised shipping date can affect your account health and ability to offer backordered products.
Yes, a stockout stops new sales, and Amazon gives greater weight to recent sales when calculating Best Sellers Rank. An out-of-stock offer also cannot become the Featured Offer, and Sponsored Products ads for that item pause automatically. Rankings and visibility may recover after sales resume, but the timeline varies by product, category, competition, and stockout length.
No, FBA does not support backorders. When FBA inventory reaches zero and no other offer is available, the product becomes unavailable for purchase. Merchant-fulfilled sellers can use a restock date to offer a backorder-style purchase window, provided they can ship the order within 30 days.
Backorders allow businesses to continue accepting purchases during temporary inventory gaps instead of losing every sale. They work best when demand remains strong, the restock timeline is reliable, and customers receive clear delivery expectations.
A reorder point is the inventory level that triggers your next replenishment order.
Reorder point = average daily sales × supplier lead time + safety stock
Calculate it separately for each product using current sales velocity, supplier lead times, and enough safety stock to cover unexpected demand or shipping delays.
Restock enough inventory to avoid another immediate stockout, confirm that the offer is active, and restart Sponsored Products campaigns around your proven keywords and targets. A temporary promotion may help restore conversions if your margins allow it. Avoid unnecessary major listing changes while performance stabilizes, and closely monitor sales, advertising, conversion rate, and inventory. Recovery may take days or weeks, depending on the product and the length of the stockout.
The FBA and FBM hybrid strategy uses two offers under the same Amazon Standard Identification Number: one FBA offer and one FBM offer, each with a separate SKU. If FBA inventory runs out, the FBM offer can help keep the product available for purchase using backup inventory stored in-house or with a third-party logistics provider. This can reduce the impact of an FBA replenishment delay, but it does not guarantee that rankings or Featured Offer placement will remain unchanged.