A beauty brand with 2,000 units of a small serum bottle sitting at 400 days in FBA gets hit with $600 in surcharges in a single month. The product takes up 0.02 cubic feet per unit. Under the old cubic-foot-only rate, the bill would be around $280. The difference? Amazon introduced per-unit minimums in the 366+ day tiers. Small products that barely occupy space now incur meaningful per-unit charges. Most sellers find out the hard way.

Amazon completely overhauled its long-term storage fee system. The old Long-Term Storage Fee (LTSF) applied a flat rate to inventory stored 365+ days, assessed twice a year. Amazon replaced it with the Aged Inventory Surcharge (AIS), which starts at 181 days, uses tiered age bands, and gets assessed monthly. If you're still planning around the 365-day threshold, you're six months too late.

This guide covers the current aged inventory surcharge structure, how to calculate your exposure, and the strategies that actually reduce storage costs when you're managing dozens to hundreds of SKUs.

What Are Amazon Long-Term Storage Fees (Aged Inventory Surcharge)?

Amazon charges monthly storage fees on all inventory in its fulfillment centers. Standard monthly storage fees apply to all units regardless of age. The aged inventory surcharge is an additional fee that kicks in once inventory sits in FBA for more than 180 days.

Amazon renamed the fee in 2023. It was the Long-Term Storage Fee (LTSF). Now it's the Aged Inventory Surcharge (AIS). Sellers search for both terms. Amazon's help docs use "aged inventory surcharge." The URL slug on this page still references "long-term storage" because that's what people type into Google.

The surcharge exists to discourage sellers from using FBA as long-term warehouse space. Amazon wants inventory that moves. Slow-moving or stale products take up space that could go to fast sellers. The fee structure reflects that: the longer inventory sits, the steeper the charge.

Current Aged Inventory Surcharge Rates (2026)

Amazon assesses the surcharge monthly on the 15th. The system takes a snapshot of your inventory age on that date. If a unit crosses into a new age tier between assessments, it gets charged the higher rate at the next monthly snapshot.

The per-unit minimums in the 366+ day tiers are the detail most sellers miss. Amazon charges whichever amount is higher: the cubic foot rate or the per-unit rate. For small, lightweight products, the per-unit minimum is almost always the higher amount.

The per-unit minimum protects Amazon from sellers storing thousands of tiny items indefinitely for pennies. It makes aged inventory removal urgent even for products with minimal cubic footage.

The 271–365 day tier has size-based variation. Standard-size items may see $3.80 per cubic foot while oversize items hit $5.90 per cubic foot. Check your Seller Central Inventory Age report for the exact rate applied to your ASINs.

Amazon adjusts FBA fee schedules annually, usually announced in Q4 for the following year. Always verify the current rates in your Seller Central account before calculating exposure.

How to Calculate Your Aged Inventory Exposure

Step 1: Pull your Inventory Age report

In Seller Central, go to Reports → Fulfillment → Inventory Age. This report shows every ASIN in FBA broken down by age bands: 0–90 days, 91–180 days, 181–270 days, 271–365 days, 366+ days.

You'll see:

• Units in each age band
• Cubic feet occupied
• Estimated monthly surcharge cost

Step 2: Identify which ASINs are aging into surcharge territory

Filter for inventory in the 181+ day bands. These are the products currently incurring surcharges. Then look at the 91–180 day band. These products will cross into surcharge territory in the next 1–3 months if they don't sell or get removed.

Step 3: Calculate your monthly exposure

Multiply units by the per-cubic-foot rate for each age band. Then compare that to the per-unit minimum. Take the higher amount for each ASIN, then sum across your catalog.

Step 4: Project future surcharges

Look at your sell-through rate for aging inventory. If units in the 181–270 day band are selling fewer than 30 units per month, they'll likely roll into the 271–365 day tier and incur higher charges. If sell-through is under 10 units per month, they'll hit the 366+ day tier and trigger per-unit minimums.

When Are Aged Inventory Surcharges Assessed?

Amazon assesses the surcharge on the 15th of every month. The system snapshots your inventory at that moment. Any unit that has been in FBA for 181+ days on that date gets charged.

If a unit sells on the 16th, you still paid the surcharge for that month. If a unit crosses from 179 days to 181 days on the 14th, it gets charged starting on the 15th.

The charge appears on your FBA fee statement as a line item labeled "Aged Inventory Surcharge" or "Long-Term Storage Fee" (Amazon still uses both terms inconsistently in reporting).

How FBA Capacity Limits Affect Your Storage Strategy

Amazon's Inventory Performance Index (IPI) score controls how much storage capacity you get. The IPI measures:

• Sell-through rate
• Excess inventory percentage
• Stranded inventory (listings without active offers)
• In-stock rate for popular products

If your IPI score drops below the threshold (historically 350–450, check your Seller Central account for the current number), Amazon restricts your restock limits. You can't send in new inventory even if you want to.

Aged inventory directly feeds the "excess inventory percentage" component of IPI. Products with more than 90 days of supply on hand count as excess. Products sitting at 181+ days are severely excess. Removing or liquidating aged inventory improves IPI and unlocks restock capacity.

Amazon moved to monthly restock limits in 2024. You can see your current capacity limit in Seller Central under Inventory → Capacity Monitor. Some sellers can purchase additional capacity through FBA capacity reservations (an auction-based system). But the base limit is still tied to IPI.

If you're close to your capacity limit, every cubic foot occupied by aged inventory is a cubic foot you can't use for fast-moving products. The opportunity cost of holding aged inventory is higher than the surcharge itself.

7 Strategies to Reduce or Avoid Aged Inventory Surcharges

1. Use Amazon Warehousing & Distribution (AWD) as a clock reset

AWD is Amazon's upstream bulk storage solution. You send inventory to an AWD facility, and Amazon auto-replenishes FBA fulfillment centers as needed. The key detail: the aged inventory clock does not start until inventory moves from AWD into FBA.

If you have a slow-moving product with seasonal demand, send the full year's supply to AWD. Amazon moves units into FBA in small batches as needed. Those units start fresh each time. You avoid surcharges on the bulk inventory sitting in AWD.

AWD storage fees are lower than FBA monthly storage fees. As of 2026, AWD charges around $0.48–$0.60 per cubic foot per month depending on product size. No aged inventory surcharges apply.

Tradeoff: AWD replenishment takes 2–5 days. If you're managing fast-moving inventory with tight restock windows, AWD isn't fast enough. It works best for products with predictable but slow demand (10–50 units per week) or seasonal spikes.

2. Set automated removal thresholds before you hit 181 days

Amazon offers an automatic removal setting. When inventory reaches a specific age threshold, Amazon automatically creates a removal order. You can set the threshold at 180 days to pull inventory before the first surcharge tier hits.

Go to Settings → Fulfillment by Amazon → Automatic Removal Settings. Enable automatic removals and set the age threshold.

Tradeoff: Removal and disposal fees apply. Removal fees range from $0.25 to $1.20 per unit depending on size tier (Amazon reduced some removal fees for 2026). Disposal is cheaper but you lose the inventory. Run the math: if the removal fee is $0.50 per unit and the surcharge would be $0.30 per unit per month, removal saves money after 2 months.

3. Use Deals and Promotions to move aging stock before the surcharge tiers hit

Products in the 91–180 day band are at risk of rolling into surcharge territory. Run Lightning Deals, Coupons, or Prime Exclusive Discounts to accelerate sell-through.

Check the Inventory Age report weekly. Identify products in the 120–180 day range with low velocity (fewer than 30 units per month). Those are candidates for promotions.

Tradeoff: Discounting erodes margin. If your product has a 30% margin and you discount 20% to move it, you're left with 10% margin. Compare that to paying $0.30/unit/month in surcharges for 3–6 months. Sometimes the surcharge is cheaper.

4. Liquidate through Amazon Outlet or third-party liquidators

Amazon Outlet is a dedicated storefront for overstock and closeout inventory. Sellers can list products at deep discounts. Amazon gives these listings additional visibility in search and browse.

To list on Amazon Outlet, go to Inventory → Manage All Inventory, select the ASIN, and choose Create Outlet Deal. You set the discount (typically 30–70% off). Amazon handles the rest.

Alternative: Use third-party liquidators like B-Stock, Liquidation.com, or Direct Liquidation. They purchase aged inventory in bulk at a steep discount (often 10–30% of retail value). You take a loss, but you recover some cash and eliminate future surcharges.

Tradeoff: Deep discounting damages brand perception if the products end up on discount sites or reseller channels. Liquidation is a last resort for inventory that has zero FBA sell-through.

5. Create removal orders and restock through multi-channel fulfillment or a 3PL

If a product sells well on Shopify, eBay, or Walmart but is slow on Amazon, pull it from FBA and fulfill through a 3PL or your own warehouse. Use Multi-Channel Fulfillment (MCF) if you want Amazon to fulfill off-Amazon orders.

Create a removal order in Seller Central. Amazon ships the inventory to the address you specify. You pay removal fees but eliminate surcharges.

Tradeoff: MCF fees are higher than FBA fees. 3PL storage may be cheaper than FBA monthly storage, but you lose Prime eligibility if you pull inventory entirely out of FBA. This works best for products where Prime eligibility doesn't drive conversions.

6. Forecast demand before sending inventory to FBA

Aged inventory is almost always a demand forecasting failure. You sent too much inventory relative to actual sales velocity. Fixing aged inventory after the fact is expensive. Preventing it is cheaper.

Use your Inventory Planning report in Seller Central. Amazon shows recommended restock quantities based on recent sales velocity and lead time. Don't override the recommendation unless you have a specific reason (upcoming promotion, seasonal spike, supply chain delay).

If you're managing a large catalog (50+ SKUs), use inventory planning software (RestockPro, SoStocked, Forecastly) to automate restock decisions. These tools integrate with Seller Central and flag products at risk of aging.

Tradeoff: Conservative restocking increases stockout risk. Stockouts hurt your organic ranking and IPI score. Balance the risk: it's usually better to stock out for 2–3 days than to carry 6 months of excess inventory.

7. Monitor Inventory Age reports weekly and act on the 120-day warning zone

Inventory in the 120–180 day range is the action zone. It's not yet incurring surcharges, but it's close. This is the window where you can still run promotions, increase ad spend, or create bundles to accelerate sell-through before the 181-day cliff.

Set a recurring calendar reminder to review the Inventory Age report every Monday. Identify products in the 120–180 day band with low weekly velocity (under 5 units per week). Triage:

• High-margin products with seasonal demand: send to AWD or hold if Q4 demand is coming
• Low-margin products with no demand recovery in sight: remove or liquidate
• Mid-margin products with moderate velocity: run a 2-week promotion and reassess

Tradeoff: Weekly monitoring takes time. If you're managing 200+ SKUs, delegate this to an operations analyst or hire an agency to monitor it for you.

When to Hold vs. Remove vs. Liquidate

Not all aged inventory should be removed immediately. Sometimes paying the surcharge is cheaper than the alternative.

How an Amazon Agency Handles Aged Inventory

Managing aged inventory across 50–500 SKUs requires operational infrastructure that most brands don't have in-house. An agency monitors inventory age across the full catalog, sets automated alerts, and makes removal or liquidation decisions based on portfolio-level economics rather than individual ASIN panic.

SupplyKick manages FBA inventory for dozens of brands. We track inventory age weekly, flag products in the 120–180 day warning zone, and coordinate removal or AWD transfers before surcharges hit. We also absorb storage fees that result from supply chain delays or strategic decisions we make on behalf of our partners. If we forecast demand incorrectly, we pay the surcharge.

Most sellers treat aged inventory as an emergency when the bill arrives. Agencies treat it as a continuous monitoring task with proactive interventions. The difference: a seller might notice a $2,000 surcharge on their monthly statement and scramble to create removal orders. An agency sees the inventory aging into the 150–180 day band, runs a Lightning Deal, and moves 70% of the units before the surcharge clock starts.

The agency model also allows for smarter liquidation decisions. A brand with a single aged ASIN has limited negotiating power with liquidators. A brand with 10 aged ASINs can bundle them into a larger lot and get better recovery rates.

If your catalog has more than 50 SKUs, aged inventory management becomes a data operations problem. That's where agencies add the most value.

Frequently Asked Questions

Conclusion

Amazon's aged inventory surcharge system penalizes inventory that sits in FBA for more than 180 days. The fee structure is tiered, starts earlier than most sellers expect, and includes per-unit minimums that trap small products. If you're still planning around the old 365-day threshold, you're already incurring surcharges.

The strategies that work at scale: AWD clock resets for slow movers, automated removal thresholds at 180 days, weekly monitoring of the 120–180 day warning zone, and cost-benefit triage on whether to hold, remove, or liquidate. Brands managing 50+ SKUs need operational infrastructure to monitor inventory age continuously and intervene before surcharges hit.