An Amazon fulfilment centre is a facility where Amazon receives and stores stock for Fulfilment by Amazon (FBA), then picks, packs and dispatches products when customers order them. For a UK seller, sending a shipment is only the beginning: stock must be checked in before it can become available for sale, and Amazon may move it between sites.
Amazon assigns the shipment destination when you create a shipment in Seller Central; you do not choose a fulfilment centre yourself. Understanding what happens after dispatch helps you interpret inventory statuses and plan replenishment without assuming that stock is ready to sell as soon as it leaves your premises.
Arrival and check-in
When a shipment reaches its assigned destination, Amazon needs to receive it against the shipment information in Seller Central. A carrier showing a parcel as delivered does not necessarily mean every unit has been checked in or is available to customers. Look at the shipment and inventory statuses in Seller Central rather than relying on the carrier update alone.
Clear, accurate labelling helps Amazon identify which shipment and product each package or unit belongs to. Packaging matters too: units need to arrive protected and prepared so they can be handled and identified correctly. An unreadable label, a mismatch between the physical stock and the shipment information, or damaged packaging can make receiving less straightforward. Check the applicable requirements before sending stock; our Amazon FBA packaging requirements guide explains what to consider.
This is not a reason to resend stock simply because it has not appeared as available yet. First, check what Seller Central says about the shipment and its units. If something appears inconsistent, use the shipment details to investigate the discrepancy.
Storage and inventory availability
After receiving, Amazon stores FBA units within its fulfilment network. Stock may be moved between sites as Amazon positions inventory to fulfil customer orders. The destination assigned to your inbound shipment is therefore not necessarily the only place that will handle those units.
For replenishment planning, the distinction is between stock you have sent and stock customers can buy. Units in transit, being received or being moved may not appear in your available quantity. Some stock may appear as reserved while Amazon processes or transfers it; reserved does not, by itself, mean the stock is lost. The guide to reserved FBA inventory explains how to interpret that status and when to look more closely.
Keep your own record of what you sent and compare it with Seller Central as the shipment progresses. That makes it easier to distinguish an expected change in status from a quantity you need to investigate.
Picking, packing and dispatch
When a customer orders an available FBA product on amazon.co.uk, Amazon handles the fulfilment work: locating the unit, picking it from inventory, packing the order and dispatching it to the customer. The seller remains responsible for managing their listings and deciding when to replenish stock, but does not pack each FBA customer order themselves.
This is the practical difference between sending stock into FBA and holding it yourself for each sale. It also means that the quantity available to sell can change as customers order and as Amazon processes inventory. Check the current inventory view in Seller Central when making stock decisions rather than treating an earlier shipment quantity as your present availability.
If you are preparing your first inbound shipment, use the separate guide on how to send products to Amazon FBA. It covers the shipment process; this article focuses on what happens to the stock afterwards.
Customer returns
Amazon also handles the customer-facing return process for FBA orders. A returned unit is not automatically available for sale again: its condition and return status matter. Check the returns and inventory information in Seller Central to see what has happened to a unit rather than adding every return straight back to your sellable stock forecast.
Returns can affect the stock you have available even when your next inbound shipment is already on its way. Monitor them alongside sales and inbound inventory so your replenishment decisions reflect the stock that can actually fulfil orders.
Plan replenishment for the whole stock journey
A replenishment plan should account for more than the journey from your premises to Amazon. Allow for the period stock spends in transit, the receiving process and any time it is not yet available while Amazon processes or moves it. Compare current available inventory with demand and incoming shipments before deciding when to send more.
Build your plan around what Seller Central shows, then revisit it as sales and shipment statuses change. The restock calculator can help you think through when to replenish; the UK seller tools hub has other calculators for planning your FBA business. Neither replaces checking the live status of your stock before you act.