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Inventory Management

Inventory Age

The number of days units have been stored in Amazon's FBA fulfillment centers. Aged inventory (180+ days) incurs escalating surcharges.

What Is Inventory Age?

Inventory age tracks how long each unit has been sitting in Amazon's warehouse. Amazon provides age brackets (0-90, 91-180, 181-270, 271-365, 365+ days) in the Inventory Age report.

Why It Matters

Units older than 180 days incur the aged inventory surcharge. The longer they sit, the more you pay. At 365+ days, the fees can exceed the product's value.

How SellerLegend Helps

SellerLegend tracks inventory aging alongside profitability data, so you can make informed decisions about promotions, price reductions, or removal orders before surcharges hit.

Related Terms

IPI Score (Inventory Performance Index)

Amazon's metric (0-1000) that measures how efficiently you manage FBA inventory. Scores below the threshold can result in storage limits and higher fees.

Aged Inventory Surcharge (Long-Term Storage Fee)

An additional fee Amazon charges for inventory stored in FBA warehouses for more than 180 days. Previously called Long-Term Storage Fee (LTSF). Increases significantly at 270+ and 365+ days.

Sell-Through Rate

The number of units sold and shipped over the past 90 days divided by the average number of units in FBA inventory during that period. Higher is better.

Track This in SellerLegend

FBA Storage & Shipment Tracking

Monitor FBA inventory across all fulfillment centers with detailed storage cost tracking and inbound shipment status. Track monthly storage fees, long-term storage charges, aged inventory, and receive shipments to avoid surprise costs and optimize warehouse placement.

Inventory Management & Forecasting

Prevent Amazon FBA stockouts and reduce excess inventory costs. Track sales velocity across multiple time periods, get a recommended purchase date, and get data-driven quantity recommendations to maintain optimal stock levels.

Want to track this metric continuously?

SellerLegend gives you a frequently-updated dashboard with all the Amazon metrics that matter.

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