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How to avoid or minimize long-term storage fees in Amazon
18 March 2026
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To provide an A-to-Z e-commerce logistics solution that would complete Amazon fulfillment network in the European Union.
Your sales look fine. Orders are coming in. Nothing seems off at first glance. But then you check your Amazon fees invoice… and something doesn’t add up. The invoice is much higher than before, and there's a new item called "long-term storage fees." Why are your costs going up?
The truth is that some of your products have simply been sitting in Amazon’s warehouse longer than expected — and Amazon is starting to charge you extra for that time. The warehouse space is limited (especially during peak season), and Amazon has thousands of brands to cater to, so if your products sit in the warehouse for longer than expected, you will get charged for the extra space you are using. Once inventory crosses specific age thresholds — like 181 or 365 days — it becomes eligible for additional, high fees, which Amazon applies during its monthly assessments.
How can you avoid those? That's what we'll be talking about today - what long-term storage fees really are, when Amazon applies them, and why they show up even when your business seems to be running normally.
What are long-term storage fees?
Long-term storage fees are additional charges Amazon applies when your products stay in its fulfillment centers for too long. They’re separate from standard monthly storage fees. You’re already paying for storing your inventory in Amazon warehouses — but if certain units don’t sell within a specific timeframe, Amazon starts charging you extra for keeping them there.
Why? Because Amazon’s fulfillment network is designed for fast-moving inventory. The longer your products sit on a shelf, the more space they take up — and the less efficient the system becomes. So instead of acting like a traditional warehouse and letting the items stay inside as long as needed, Amazon uses pricing to push sellers toward one goal: keep your inventory moving.
This is where the concept of aged inventory comes in.
In simple terms, aged inventory refers to products that have been stored in Amazon’s fulfillment centers for an extended period of time without being sold. Once items cross certain time thresholds, they become eligible for additional fees — regardless of whether they’re still sellable or not. That’s why long-term storage fees aren’t really about storage itself, rather they’re about inventory turnover. If your products aren’t selling fast enough, Amazon treats them as a problem for their warehouse system — and prices those problems accordingly.
What counts as aged inventory?
While letting products stay at their inventory, Amazon tracks the age of each individual unit from the moment it’s received at the fulfillment center. Their warehouse space is limited after all, and they have thousands of stores to cater to, so Amazon does a lot to ensure that their space is used as efficiently as possible. And that includes monitoring the SKU's in their warehouse for how quickly (or slowly) they sell, with the slow sellers being treated as "aged inventory".
So what exactly counts as “aged”?
Amazon groups your inventory into time-based categories:
0–90 days → healthy inventory
91–180 days → slower-moving, but still safe
181–365 days → at risk (eligible for additional storage fees)
365+ days → long-term aged inventory (highest fee level)
The key threshold to watch is 181 days. Once a unit crosses that point, it enters Amazon’s aged inventory category — and from there, it’s only a matter of time before additional fees apply if it doesn’t sell.
You can find the information about how "aged" your own stock is in two places:
Inventory Age report
Shows exactly how many units fall into each age bracket (e.g. 181–270 days, 271–365 days, 365+ days)Inventory Health report
Flags excess and slow-moving inventory, and often suggests actions like price reductions or removals
If you open these reports, you can find how many units are getting close to the fee threshold, and how fast that number is growing.
Let’s say you notice a few hundred units sitting in the 181–270 day range. At first glance, that might not seem critical. But when you compare it to your actual sales velocity, the picture changes. If you’re only selling a small portion of that stock each week, a large part of it will likely cross into the next age bracket before it has a chance to sell. And once units move closer to the 365-day mark, your ability to react becomes much more limited. This is exactly where metrics like sell-through rate and IPI come into play and show what’s really happening in your inventory.
Your sell-through rate shows whether your inventory is clearing fast enough compared to how much you’re holding. If it’s low, it usually means products are staying in storage longer than they should — which directly leads to aging stock. The IPI score pulls this into a bigger picture. When it drops, it’s often because too much of your inventory is either sitting unsold or already aging, and Amazon starts treating your stock as inefficient.
The important part is that none of this happens suddenly. The signals are there in advance — in your reports, in your sales velocity, and in how your inventory is distributed across age brackets. But if nothing changes, those early signals eventually turn into additional fees.
When and how Amazon charges long-term storage fees
Long-term storage fees are applied on a fixed schedule — and once you understand that schedule, it becomes much easier to predict (and avoid) them.
Amazon evaluates your inventory on the 15th of every month. On that day, it takes a snapshot of your stock and checks the age of each individual unit stored in its fulfillment centers. The clock starts the moment a unit is received by Amazon (not based on when you created the listing or when you last restocked) — and it keeps ticking until that specific unit is sold, removed, or disposed of.
During this monthly assessment, Amazon groups your units into age brackets, such as:
181–270 days
271–365 days
365+ days
Any units that fall into these ranges, especially those beyond 181 days, are flagged as aged inventory.
To calculate the fee, Amazon determines how much space each unit occupies in the warehouse (measured in cubic feet) and then it compares two values:
a storage fee based on volume
a minimum fee per unit
Amazon automatically applies whichever of these two is higher.
If you’re storing larger products — for example, home goods or bulky items — the fee is usually driven by how much warehouse space they occupy. Even a relatively small number of unsold units can generate noticeable costs, simply because each item takes up more cubic volume.
With smaller products, the dynamic is different. They don’t take up much space, so the volume-based fee stays low — but once they pass the aging threshold, the minimum per-unit fee becomes the dominant cost factor. That means even lightweight, low-cost items can start generating disproportionate storage costs if they sit long enough in Amazon’s warehouse.
Another important detail is how Amazon assigns age to inventory when you send multiple shipments over time.
Amazon uses a FIFO system (first-in, first-out), which means it assigns sales to the oldest units in your inventory first — at least from a reporting perspective. For you, this creates a situation where the age of your inventory doesn’t reset when you send in new stock.
Let’s say you send 1,000 units of a product in January. By July, 400 of them are still unsold — so they’re approaching the 181-day threshold. In the meantime, you send another 1,000 units in June because the product is still selling. In Amazon’s system, those remaining 400 units from January are still aging though. Even if you continue to sell the product every day, those older units may not clear fast enough before they cross into the next age bracket.
So you can end up in a situation where:
you’re actively selling the product
you’ve recently restocked it
but a portion of your inventory still becomes eligible for long-term storage fees
This is why restocking alone doesn’t solve the problem. If older inventory isn’t cleared quickly enough, it continues aging in parallel — and eventually triggers additional costs.
Common situations that lead to long-term storage fees
For Amazon, their warehouse rules are straightforward and easy to predict - units enter the warehouse, don’t sell fast enough, cross the 181-day threshold, and stay there long enough to trigger additional fees. For sellers, it's not that easy though, as their business might still look “active” — you’re selling, restocking, and think the sales speed should be enough to meet Amazon's demands. However, there are a few situations where inventory can overfill the inventory and age very quickly:
Seasonal stock that stays too long after peak demand
You prepare for a strong sales period — for example, Q4. In October, you send 3,000 units to Amazon to make sure you don’t run out of stock during peak demand. Sales are strong in November and December, but by the end of the season you still have 1,200 units left in FBA. In January, sales drop significantly — instead of selling 50 units a day, you’re now selling 8–10.
At that pace, a large portion of those remaining units will still be in storage 3–4 months later. By spring, they start crossing the 181-day threshold. And if sales don’t pick up again, some of them will continue aging toward 365+ days — even though the product itself is still “active” and selling.
Overstock after restocking
You see strong sales — for example, around 30 units per day — so you decide to scale. Instead of sending your usual 1,000 units, you increase your next shipment to 3,000 to avoid stockouts and support growth. But after a few weeks, demand stabilizes at a lower level — around 15 units per day.
At that pace, you’re now selling roughly 450 units per month, while holding 3,000 units in stock. Even without sending any additional inventory, it will take over 6 months to clear what’s already in Amazon.
That’s where the problem starts.
After the first 3 months, a large portion of your inventory is still sitting in the 90–180 day range. By month 6, some of those units begin crossing the 181-day threshold. And because your sales velocity isn’t high enough to catch up, part of that inventory continues aging into the next brackets. From a dashboard perspective, everything still looks “fine” — you’re selling every day, and you’re not overstocked in an obvious way. But in the background, your inventory is no longer rotating fast enough to avoid long-term storage exposure.
Products with inconsistent or declining demand
Your product launches strong and stabilizes at around 25–30 units sold per day. Based on that, you send in 2,000 units, expecting to sell through in roughly 2–3 months. But a few weeks later, something shifts. Your conversion rate drops from 12% to 7%, or your product loses a top search position. Sales fall to 10–12 units per day.
At that point, your original plan no longer holds.
Instead of clearing inventory in 3 months, you’re now looking at 5–6 months just to sell what’s already in stock. That means a large portion of those units will still be sitting in Amazon when they approach the 181-day threshold.
The tricky part is that nothing “breaks” completely. You’re still selling every day, orders are coming in, and the listing is active. But the drop in sales velocity is enough to push part of your inventory into the aging range — and eventually into long-term storage fees.
Listing or operational issues
An even trickier problem is when a listing issue slows down sales without completely stopping them.
Let’s say your product was selling around 20 units per day. Then your listing gets partially suppressed — for example, due to a missing attribute or compliance flag — and your sales drop to 4–5 units per day. The listing is still live, orders are still coming in, and the issue isn’t always immediately visible in your main dashboard. But when you look at your inventory levels, the impact becomes clear.
If you’re holding 1,500 units in stock, selling 20 units per day would clear it in about 2–3 months. At 5 units per day, that same inventory now takes 9–10 months to sell. That shift alone is enough to push a large portion of your units past the 181-day threshold — and potentially toward 365+ days — even though the product never “stopped” selling.
From Amazon’s perspective, the cause doesn’t matter. The only thing that counts is how long those units stay in storage — and once they cross the threshold, the fees apply automatically.
Where the fees actually start
Long-term storage fees don't appear out of the blue - they are a signal that a part of your inventory is no longer aligned with how fast Amazon expects it to move. You can see the misalignment clearly in your sellers' center, when your current stock level divided by your daily sales gives you 5–6 months of coverage or more or where a part of your stock is marked as "aged". For Amazon, every meter of their warehouse space is precious and thus needs to be used as efficiently as possible - and fees for overstocking are one way to achieve this.
But now that you know where to look to find information about your products age, it should be far easier to pinpoint the exact SKUs that brought the extra fees onto your invoice. In the next article, we'll talk about how you can avoid or minimize those fees, so you could take action and lower your storage fees yourself.
