Operator glossary
Aged inventory surcharge
Escalating monthly storage penalties on FBA stock older than 181 days — the fee that turns a slow SKU into a negative-margin one if nobody is watching sell-through.
On top of normal storage fees, Amazon adds a per-cubic-foot surcharge that starts at 181 days in the network and escalates in bands — by the time units cross a year, the surcharge alone can exceed the product's storage cost several times over. It is charged on inventory age, not on whether the listing is active or the brand is trying.
Manage it with a monthly aged-inventory review: anything approaching 181 days gets a decision — discount it out, run a removal order, or accept the fee deliberately for genuinely seasonal stock. The expensive outcome is the default one, where nobody decided anything.
The numbers
- Charged monthly on top of base storage, per cubic foot, by age band: ~$0.50/cu ft at 181–210 days, ~$1.50 at 241–270, ~$5.45 at 271–300, and $6.90 (or $0.15/unit, whichever is greater) at 365+.
- Age is tracked per unit, first-in-first-out — selling newer stock does not reset older units' clocks.
Primary sources: Amazon selling fees (official)