FBA Capacity Limits on Amazon UK: How They Work and What to Send First
Amazon limits how much stock each seller can hold and send to its UK fulfilment centres. When you hit the limit, new shipments stop. This guide explains how the limits work, where to find yours and what to send first when space is tight.
Amazon sets a capacity limit for your account by storage type, such as standard-size and oversize, and reviews it regularly. Your stock on hand plus what is inbound counts against it. Amazon bases the limit on things like your sales history, forecast demand and how efficiently you use the space. The way to get more room is to sell through what you have and stop sending stock that sits.
Where to see your limit
On UK accounts, capacity shows on the FBA dashboard and the capacity monitor (under Inventory › FBA Inventory or the inventory performance pages, depending on your menu). It shows each storage type with your limit, current usage and the room left, and often an estimate for the coming period. Check it before you buy, not just before you ship.
What counts against it
- Units in fulfilment centres, sellable or not. Stranded and unfulfillable units still use space.
- Units in open inbound shipments, from the moment the shipment is created.
- Different storage types are tracked separately, so a full oversize limit does not stop standard-size shipments.
That is why clearing stranded and unfulfillable stock is often the quickest way to free room. See stranded inventory and removal orders.
Why limits move
Amazon does not publish the exact calculation and changes the approach from time to time. Its help pages describe the inputs in general terms: sales, forecast demand, fulfilment centre space, and inventory performance measures such as how much excess or aged stock you hold. New accounts usually start with a modest limit that grows with sales. Expect limits to tighten around peak, when space is busiest.
Open inbound shipments count against your limit, so a shipment created "just in case" blocks room you might need for a faster seller. Cancel or reduce shipments you are not about to send.
What to send first when space is tight
- Fast sellers with low cover. Running out costs you the Buy Box and sales rank; see Buy Box basics.
- Higher-profit units per unit of space. A small, high-margin item earns more per cubic foot than a bulky low-margin one.
- Stock already bought and paid for that sells well, before new speculative buys.
- New test lines in small quantities, last.
Keep slow or seasonal stock at home or at a prep centre and send it in smaller batches. Some sellers fulfil part of their range themselves (FBM) when capacity is short; that has its own performance rules, covered in our FBM delivery rate guide.
Improving your position
- Keep sell-through steady: buy quantities you can sell within a few weeks, not months.
- Clear aged stock before it attracts surcharges and weighs on your inventory performance. See storage fees and aged inventory.
- Fix stranded listings and remove unfulfillable units every week.
- Keep listing dimensions accurate, since wrong measurements make each unit use more of your limit.
If you are just setting up, the free UK FBA Starter Framework is a 47-step checklist that covers the account, tools and first shipments. The £29 Amazon FBA Playbook goes further on the admin side: the weekly report routine, cash flow and how to keep stock moving.
Sources
- Amazon Seller Central UK Help: “FBA capacity limits” and “Capacity monitor” (login required).
- Amazon Seller Central UK Help: “Inventory Performance” and “FBA inventory” pages (login required).
- Amazon UK: Fulfilment by Amazon overview (reviewed 27 October 2026).
Amazon Seller Central help pages need a seller login, so we cite them by page title. Reviewed 27 October 2026. This article is general guidance, not a statement of Amazon's policy; Amazon's current wording always takes precedence.