Amazon Storage Fee Calculator

How Amazon FBA Storage Fees Work

Packaging is where most sellers quietly overpay. Amazon bills storage on the daily average volume of each unit as it sits packaged and ready to ship, so the air inside an oversized box costs money every month.

Trim the carton and the fee drops, even though the product is identical. Units pending removal come out of the average too, so a removal order stops the meter as soon as you place it.

Volume is the longest side times the median side times the shortest side, divided by 1,728 to convert cubic inches to cubic feet. A 12 by 9 by 3 inch carton is 0.1875 cubic feet. Multiply by the units you hold and by the rate, and you have the fee for that product. Charges post typically between the 7th and 15th of the following month.

Base monthly rates

Peak Season: Why Q4 Costs So Much More

October is the month that wrecks storage budgets. Standard-size space jumps from $0.78 to $2.40 per cubic foot, roughly triple, and nothing about your product has to change for that to happen.

Picture 200 units at 0.2 cubic feet, or 40 cubic feet total. July costs you $31.20. November costs $96.00. That $64.80 gap is pure calendar.

Oversize items get hit too, just less hard: $0.56 per cubic foot off-peak and $1.40 in peak. The same 40 cubic feet goes from $22.40 to $56.00.

Our view is blunt. Anything you expect to sell by September should be gone by October, and the peak-versus-off-peak line in the calculator exists to make that cost impossible to ignore.

Storage Utilization Surcharge: Who Pays It

Amazon adds the storage utilization surcharge only on units aged over 30 days, and only for sellers who meet four conditions: a Professional account, a first US fulfillment center shipment more than 365 days ago, average daily volume of at least 25 cubic feet for the size tier, and a ratio above 22 weeks. New sellers, Individual accounts and anyone under 25 cubic feet are exempt, so do not tick that box in the calculator unless all four are true for you.

The ratio is your daily inventory volume over the past 13 weeks divided by your daily shipped volume over the same 13 weeks, divided by 7, and it is calculated separately per size tier. The ratio on the last day of the month sets that month's surcharge, so a clean-up late in the month still counts. Amazon says pending-removal volume is excluded and that the ratio is visible on the FBA Dashboard.

We like that Amazon publishes a worked example, because it lets you check the calculator against their own math. In July, 100 units of 0.05 cubic feet at a 14 week ratio cost $3.90. Push the ratio to 25 weeks with 10 units older than 30 days and the surcharge adds $0.22, for $4.12. Our calculator gives both numbers. Worst case, at the top band, standard-size space runs $4.28 a cubic foot in peak.

Aged Inventory Surcharge After January 16, 2026

Amazon's aged inventory page, formerly called long-term storage, charges units stored 181 days or longer on top of the monthly fee. It uses an inventory snapshot on the 15th, typically charges between the 18th and 22nd, and counts age first-in, first-out across the whole network. Rates effective January 16, 2026 split the old 366-plus tier in two and raised the per-unit minimum from $0.15 to $0.30 and $0.35.

* Excludes clothing, shoes, bags, jewelry and watches.

The per-unit minimum is easy to miss. Amazon's example uses 20 toys at 11 by 8 by 2 inches, stored 457 days: $16.12 by volume against $7.00 by unit, so Amazon charges $16.12.

Swap in tiny parts and the result flips. That is exactly the case the minimum was written for.

A removal or disposal order submitted by 11:59 p.m. PT on the 14th avoids the surcharge for that inventory even if the units have not physically left. Amazon also lists an Outlet deal with a minimum 20% discount and says the FBA Inventory tool shows ASINs that will be subject to the surcharge within 60 days.

Dangerous Goods Storage Rates

Hazmat inventory pays its own, steeper rates. Standard-size dangerous goods cost $0.99 per cubic foot from January to September and $3.63 from October to December; oversize costs $0.78 and $2.43. Against regular stock that is about $0.21 more off-peak and $1.23 more in peak. Amazon's table shows no utilization surcharge for this category, so the calculator switches that block off.

How to Cut Your FBA Storage Costs

Amazon's own advice is short. Sell through faster, liquidate, or send units back or to disposal with a removal order, and read the Monthly Storage Fees report SKU by SKU to find the worst offenders.

Eligible units in FBA New Selection get free monthly storage and skip both the base fee and the surcharge. Those are the levers Amazon's storage FAQ names.

• Ship smaller replenishment batches before October instead of one big inbound.
• Check the FBA Inventory tool for ASINs approaching the aged surcharge.
• Submit removal or disposal orders before the 14th when a SKU is not moving.
• Measure packaged size again; trimming a carton reduces cubic feet on every unit.

Storage is only one line of your unit economics. Run the per-unit result through our Amazon FBA calculator for referral and fulfillment fees, add the storage cost per unit to your cost of goods sold, and check what is left in the profit margin calculator. A product that looks fine at $0.78 can look very different at $2.40.