Aged Inventory Surcharge (Amazon)
Definition
An extra monthly fee Amazon charges on FBA inventory that has been sitting in its warehouses too long. In 2026 the surcharge starts at 181 days and gets steeper as inventory ages past 271 and 365 days.
Want a deeper explanation?
This fee punishes over-ordering. A purchase that looked efficient because of a volume discount can cost more than it saved once the units sit in FBA for half a year.
Amazon adjusts these thresholds and rates regularly, so check the current schedule in Seller Central before planning a big inbound shipment. Watch for: the surcharge being lumped into general Amazon fees in your books, which hides which SKUs are costing you money to store.
Example
500 units of a slow-moving SKU pass 181 days in an Amazon warehouse. Each month they stay, the surcharge adds to your storage bill, quietly lowering the profit on every unit you eventually sell.