Why launches stock out
New Amazon launches stock out because early demand is unpredictable and sellers often send only what they can fit or afford into FBA. If a launch takes off, the listing runs dry just as it gains traction, and organic rank built during the launch fades while you wait for more inventory.
The opposite mistake is sending everything at once, which can collide with capacity limits and leave you paying storage on slow units if demand comes in lower than hoped. The answer is a launch plan that separates what you manufacture from what you send to Amazon.
Sizing the launch order
Size the launch order around a realistic range, not a single forecast. Look at comparable listings, your planned advertising budget and your supplier's lead time for a reorder. The real question is how many units you need to stay in stock until a second production run can arrive, under an optimistic scenario.
That quantity often exceeds what you should place in FBA at launch. The balance belongs in upstream storage, ready to replenish if sales outrun the plan.
Getting the listing and prep spec right first
Get the listing data and prep spec right before inventory is produced. Mistakes here are cheapest to fix at the factory.
- Confirm the ASIN, FNSKU and whether you will use FNSKU or manufacturer barcode labeling
- Check whether the product needs specific prep: polybagging, bubble wrap, liquid sealing, expiration labeling
- Check for dangerous goods triggers, such as batteries, aerosols, flammable ingredients or certain chemicals, and gather safety data sheets early
- Define case-pack: units per carton, carton dimensions and weight within Amazon limits
- Confirm packaging dimensions and size tier, since they set fulfillment and storage fees
A dangerous goods review can take time, so start it before the launch date is fixed.
Planning the first FBA shipments
Plan the first FBA shipments in waves rather than one large inbound. A first wave large enough to cover launch demand plus receiving time goes in ahead of launch. A second wave sits ready at the 3PL, prepped and boxed, to send the moment early sell-through confirms demand.
New sellers and new ASINs may have different capacity and fee treatment than established ones, so check your current limits and any new-selection programs in Seller Central before deciding wave sizes.
Watching the first weeks of sell-through
The first weeks of sell-through tell you which scenario you are in. Track daily units sold, days of cover in FBA and inbound transit time. If days of cover in FBA falls toward the time it takes to get a replenishment shipment received, trigger the next wave immediately.
Also watch returns and customer feedback for packaging or damage issues. Fixing a packaging problem before the second production run saves far more than fixing it after.
Setting the restock cadence
Once demand stabilizes, move from launch waves to a regular restock cadence. Weekly or biweekly replenishment from upstream storage usually keeps FBA lean while protecting against stockouts. Reorder from the factory based on total days of supply across FBA and the 3PL, including production and ocean transit lead time.
This is also the point to add other channels. Inventory sitting at the 3PL can serve a Shopify store or Walmart Marketplace without a separate stock purchase.
Launch checklist
Before launch day, confirm:
- Listing live with correct ASIN, FNSKU and size tier
- Prep spec documented and tested on a sample
- Dangerous goods review complete, if relevant
- First FBA wave received and available
- Second wave prepped and staged at the 3PL
- Reorder trigger defined in days of supply
A launch that stays in stock gives your marketing a fair test. One that stocks out never does.
Budgeting for launch fulfillment costs
Budgeting for launch fulfillment means accounting for more than Amazon's fulfillment fee. A realistic launch budget includes:
- Inbound freight from the factory to the U.S. and onward to the 3PL or Amazon
- Receiving and storage at the 3PL for inventory held in reserve
- Prep labor and materials: labels, polybags, inserts, bundling
- Inbound placement fees and freight for each FBA shipment
- FBA monthly storage fees, plus any surcharges if inventory sits too long
- Removal costs if a variant underperforms and needs to be pulled
Model these in a range, the same way you model demand. The goal is not a perfect number but knowing the landed cost per unit under both strong and slow launch scenarios, so you can price, advertise and reorder with confidence. Ask any prospective 3PL to quote against your actual case-pack data and expected launch waves so the estimate reflects how inventory will really move, not an idealized average. That gives you a baseline to measure the launch against once real sell-through data arrives.
After launch, hold a short review once the first reorder is placed. Compare actual sell-through with your scenarios, note which prep or listing issues came up, and update the prep spec and launch template for the next product. Brands that launch several products a year benefit most from this habit, because each launch gets faster and less risky than the one before it.
Frequently asked questions
How much inventory should I send to FBA for a product launch?
Send enough to cover expected launch demand plus inbound and receiving time, and hold additional prepped inventory at a 3PL so you can replenish quickly if sales exceed the plan.
Should a new product be prepped at the factory or a 3PL?
Either works if one party owns compliance. Factory labeling is often cheaper per unit, while a 3PL can inspect on arrival and handle bundling, inserts or relabeling that comes up after launch.
When should I reorder after an FBA launch?
Reorder based on total days of supply across FBA and upstream storage, triggered early enough to cover production time and transit before stock runs out.