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Amazon fees

Amazon Storage Fee Calculator

What Amazon charges every month just to keep your units in the FBA warehouse — the fee that quietly compounds on slow-selling inventory.

Monthly FBA storage fee = total volume in cubic feet × the monthly rate. Amazon bills storage on the cubic feet your inventory occupies, not the unit count: 500 units at 0.3 cu ft each is 150 cu ft, and at the 2026 standard-size rate near $0.78 per cu ft that is about $117 a month. Rates jump sharply in Q4 (roughly $2.40 per cu ft for standard size, October–December), and stock aged past 271 days adds a long-term storage surcharge on top. Enter your units, per-unit volume and the current rate to see the monthly bill and what each unit costs to store.

Amazon Storage Fee Calculator — your numbers

Monthly storage fee

$117.00

Storage cost per unit

$0.23

Total volume (cu ft)

150

Estimate only. Results reflect exactly the numbers you enter — verify against your own accounting before making pricing decisions.

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Worked examples

Standard months (Jan–Sep)

Units in storage 500
Cubic feet per unit 0.3
Storage rate $0.78
Monthly storage fee $117.00
Storage cost per unit $0.23
Total volume (cu ft) 150

150 cu ft at $0.78 — about $117 a month to store 500 units.

Q4 peak rate (Oct–Dec)

Units in storage 500
Cubic feet per unit 0.3
Storage rate $2.40
Monthly storage fee $360.00
Storage cost per unit $0.72
Total volume (cu ft) 150

The same inventory more than triples during the holiday storage surcharge.

Frequently asked questions

How does Amazon calculate FBA storage fees?

By volume, not by units. Amazon measures the cubic feet your inventory occupies (unit size × quantity on hand), averages it over the month, and multiplies by the monthly rate for your size tier. A small, dense product costs little to store; a bulky, slow-selling one can quietly eat its own margin in storage before it ever sells.

Why are Amazon storage fees so much higher in Q4?

Warehouse space is scarcest in the run-up to the holidays, so Amazon raises the standard-size rate from roughly $0.78 to about $2.40 per cubic foot for October through December (oversize rises too). If your product is seasonal, model both rates: carrying dead stock into Q4 is one of the most expensive mistakes on FBA.

What is the long-term storage / aged-inventory surcharge?

On top of monthly storage, Amazon charges an aged-inventory surcharge on units held a long time (tiers begin around 181–271+ days and climb steeply). It is designed to push you to liquidate slow movers. This calculator covers the base monthly fee; add the surcharge for any inventory you expect to sit past those thresholds.

How do I find the cubic feet of my product?

Multiply the packed length × width × height in inches, then divide by 1,728 (the number of cubic inches in a cubic foot). A 10×6×3-inch box is 180 cubic inches, or about 0.104 cu ft. Use the fully-packaged dimensions Amazon measures at the fulfillment center, not the bare product.

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