Profit Hawk
Free tool · For Amazon FBA sellers

Amazon FBA Storage Fee Calculator.

Estimate base monthly storage fees and the aged inventory surcharge — from the day your units land at Amazon to the day the last one ships — including Q4 peak rates and the 2026 surcharge schedule most sellers don't see coming. Storage utilization surcharge, storage overage fees, low-inventory-level fees, inbound placement service fees, removal/disposal fees, and special-program exceptions are out of scope.

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What question does this answer
“If I order this many units and sell this many per day, what will Amazon charge me in storage fees before they're all gone?”
2

What it costs to store

Total fees, month-by-month, until the last unit ships.

Total storage fees
$4,850
Across 20 months
Fee per unit
$1.62
On 3,000 units shipped
Aged surcharge
$3,286
68% of total fees
Fees vs revenue
6.47%
of $74,970 revenue

Inventory & fees over time

Order of 3,000 units · selling 5/day · shipped in Jan

Inventory on hand and monthly storage fees over time366–455 DAYS456+ DAYS$119$113$107$101$94$88$135$173$204$639$595$544$442$380$324$296$228$158$90STOCKOUT D60106001.2k1.8k2.4k3kUNITS$0$140$280$420$560$700$ / MONTHJanD1–31FebMarD60–90AprMayD121–151JunJulD182–212AugSepD244–273OctNovD305–334DecJan ’27D366–396Feb ’27Mar ’27D425–455Apr ’27May ’27D486–516Jun ’27Jul ’27D547–577Aug ’27
Inventory on handBase storage feeAged inventory surchargeAged surcharge tier (181d+)

What this meansPlain English

Storing this order in FBA is estimated to cost $4,850 across 20 months — roughly $1.62 per unit, in base monthly storage plus the aged inventory surcharge. 68% of that is the aged inventory surcharge — money you only pay because units sit in FBA on the 15th of a month past day 180. Speed up sell-through (price, ads, promos) or move the surplus to AWD/3PL before it ages.

Estimate covers base monthly storage fees and the aged inventory surcharge only. Does not include storage utilization surcharge, storage overage fees, low-inventory-level fees, inbound placement service fees, removal/disposal fees, special-program exceptions, or special-handling tiers (dangerous goods, apparel, etc.).

Month-by-month breakdown

20 months · stockout day 601

MonthStart inv.End inv.Age15th snapshot tierBase feeAged surchargeTotal
Jan3,0002,845D1–31Standard$118.83—$118.83
Feb2,8452,705D32–59Standard$112.84—$112.84
Mar2,7052,550D60–90Standard$106.84—$106.84
Apr2,5502,400D91–120Standard$100.65—$100.65
May2,4002,245D121–151Standard$94.45—$94.45
Jun2,2452,095D152–181Standard$88.26—$88.26
Jul2,0951,940D182–212181–210 days$82.06$52.73$134.80
Aug1,9401,785D213–243211–240 days$75.77$97.40$173.16
Sep1,7851,635D244–273241–270 days$69.57$133.98$203.55
OctPEAK1,6351,480D274–304271–300 days$195.00$444.23$639.23
NovPEAK1,4801,330D305–334301–330 days$175.94$418.59$594.53
DecPEAK1,3301,175D335–365331–365 days$156.87$387.19$544.06
Jan ’271,1751,020D366–396366–455 days$44.69$397.11$441.80
Feb ’271,020880D397–424366–455 days$38.70$341.41$380.10
Mar ’27880725D425–455366–455 days$32.70$291.09$323.80
Apr ’27725575D456–485456+ days$26.51$269.51$296.01
May ’27575420D486–516456+ days$20.31$207.79$228.10
Jun ’27420270D517–546456+ days$14.12$144.01$158.13
Jul ’27270115D547–577456+ days$7.92$82.29$90.21
Aug ’271150D578–608456+ days$1.81$18.52$20.32
Total over 20 months$1,563.83$3,285.85$4,849.68

2026 FBA storage rates

U.S. fulfillment · standard + oversize · the 2 main tiers

Base monthly inventory storage
Size tierJan – SepOct – Dec
Standard-size$0.78 /cu ft$2.40 /cu ft
Large bulky / Oversize$0.56 /cu ft$1.40 /cu ft
Aged inventory surchargeEFF. JAN 16 2026
Days in FCSurcharge / cu ft / monthPer-unit minimum
181–210 days$0.50—
211–240 days$1.00—
241–270 days$1.50—
271–300 days$5.45—
301–330 days$5.70—
331–365 days$5.90—
366–455 days$6.90$0.30/unit
456+ days$7.90$0.35/unit
When it's billed: Amazon assesses the aged inventory surcharge against the inventory snapshot on the 15th of each calendar month. Units cleared before the 15th skip that month's surcharge.
How aged 366+ is charged: Amazon bills whichever is greater — the per-cu-ft rate or the per-unit minimum. Small, lightweight units typically hit the per-unit minimum.
How it works

The math, in plain English.

This calculator estimates two of Amazon's FBA storage charges: a base monthly rate every unit pays based on average daily volume, plus the aged inventory surcharge — assessed on the 15th-of-month snapshot — that kicks in once a unit has been in FBA longer than 180 days. Storage utilization surcharge, storage overage fees, low-inventory-level fees, inbound placement service fees, removal/disposal fees, and special-program exceptions are not modeled.

Storage estimate=Base monthly storage+Aged surcharge (15th-of-month)
Base
Monthly inventory storage. Average daily cubic feet of inventory × the monthly rate for your size tier. Off-peak is $0.78/cu ft (standard) and $0.56/cu ft (oversize). Oct–Dec rises to $2.40 and $1.40 — a ~2.5×–3× jump depending on tier.
Aged
Aged inventory surcharge (181+ days). Assessed on the inventory snapshot Amazon takes on the 15th of each month. If units are still in FBA on the 15th, that month bills at the tier matching the units' age — starting at $0.50/cu ft and climbing to $7.90/cu ft past day 456.
366+
Per-unit minimum on long-aged units. Past day 366, Amazon bills whichever is greater — the per-cu-ft rate or a per-unit minimum ($0.30 at 366+, $0.35 at 456+). Small light units hit the per-unit minimum first — that's why a tiny SKU aged 1+ year often costs more to store than it cost to make.

Worked example

3,000-unit order, 5/day sell-through, 90 cu in per unit, standard-size, shipped in January.

Cubic feet shipped156.3 cu ft
Sell-through period600 days
First aged month (Jul 15 snapshot)Jul · 181–210 days
Months billed20 months
Base storage fees≈ $1,564
Aged surcharge≈ $3,286
Estimated total fees
≈ $4,850
Watch out for

Common FBA storage-fee mistakes.

Most "surprise" storage bills aren't a math problem — they're an assumption problem. Here are the ones we see most often inside Amazon catalogs.

01

Pretending Q4 rates don't exist

Sellers plan around the off-peak number ($0.78 standard / $0.56 oversize) and forget Amazon raises base storage roughly 2.5×–3× from October through December (standard ~3.08×, oversize ~2.5×). A 90-day Q4 hold costs roughly as much as 7–9 months of off-peak storage.

Fix: Always model with the actual ship-in month. If units arrive in Oct, the next three months bill at peak.
02

Treating “aged” as a problem for next year

The clock starts at day 181, not day 366. By day 271, the per-cu-ft rate jumps roughly 3.6× in a single tier — long before the “long-term” label feels relevant.

Fix: Treat 181 days as your action line, and 271 as the no-discussion deadline.
03

Forgetting that the surcharge is a 15th-of-month snapshot

Amazon doesn't pro-rate the aged inventory surcharge day-by-day. It takes one inventory snapshot on the 15th of each month and bills the tier matching the age of inventory on that date. Stock that clears on the 14th skips that month's surcharge; stock still in FBA on the 15th pays the full month.

Fix: When you're close to a tier boundary, time clearance/removal actions BEFORE the 15th, not just before month-end.
04

Using the wrong unit dimensions

Storage fees scale with cubic feet. Sellers measure the inner pack and forget Amazon bills off the outer pack — or use whole-inch rounding that loses 15–20% of the real volume.

Fix: Use Amazon's dimensions from the ASIN detail page. Divide cu in by 1728 to get cu ft.
05

Ignoring the per-unit minimum on aged 366+ units

Past 366 days, Amazon charges whichever is greater: the per-cu-ft rate or a per-unit minimum ($0.30 → $0.35). Small lightweight units hit the per-unit minimum first, and looking only at the cu-ft column dramatically understates the real bill.

Fix: For small items, always model both the per-cu-ft AND per-unit numbers and apply whichever is greater.
06

Buying for 12 months of cover on a slow mover

12 months of cover means roughly half of every unit ages past 180 days. On a slow SKU that's just an aged-surcharge bill waiting to happen — paid out of margin you haven't earned yet.

Fix: Cap PO size at the days-of-cover number that lands the last unit before day 180.
When this calculator isn't enough

Great for one SKU.
Tricky for a full catalog.

This tool is perfect for sanity-checking a single PO. But pricing the storage cost of an entire Amazon catalog manually falls down fast — because real catalogs aren't static.

  • One SKU at a timeReal catalogs have dozens to thousands of SKUs each with their own velocity, dimensions, and age curve.
  • Sell-through changes weeklyAds, price, promos, seasonality — daily sales drift, and your storage projection drifts with them.
  • Aged cohorts already in FBAThis tool projects from arrival. Real exposure also depends on the units already sitting at day 90, 180, 270, 365+.
  • FBA + AWD + 3PL + inboundYour true storage spend spans every warehouse plus inbound. A single-SKU FBA calculator misses the bigger picture.
  • Surcharge schedules shiftAmazon has changed the aged inventory surcharge schedule more than once. Your model has to follow the current tiers, not yesterday's PDF.
  • Trade-off math: discount vs. remove vs. transferPicking the cheapest action per SKU at scale needs margin, surcharge, removal, and transfer costs lined up automatically.
▲ Profit Hawk

Forecast FBA storage costs across every SKU, automatically.

Profit Hawk connects to your Amazon Seller Central and projects storage spend continuously — using your real sales velocity, real ASIN dimensions, and your live FBA + AWD + 3PL + inbound inventory.

  • Storage cost forecast per SKU, per month
  • Aged inventory surcharge alerts before 181 days
  • Q4 peak modeling baked in
  • FBA / AWD / 3PL placement decisions
Start free trialSee Profit Hawk →
FAQ

FBA storage, answered.

The questions Amazon sellers actually ask us — about peak rates, aged surcharges, per-unit minimums, and what to do when the numbers say liquidate.

Why are FBA storage fees higher in Q4?
Amazon raises base monthly inventory storage rates roughly 2.5×–3× from October through December, depending on size tier — $2.40/cu ft for standard-size (vs. $0.78 off-peak, ~3.08×) and $1.40/cu ft for large bulky / oversize (vs. $0.56 off-peak, ~2.5×). This is to discourage sellers from clogging FCs with non-essential inventory during the busiest selling season. The fix isn't to ship less stock — it's to ship the right stock, and to make sure slow movers are cleared before Oct 1.
What is the aged inventory surcharge?
The aged inventory surcharge is the fee Amazon charges on units that have been in FBA longer than 180 days (it's what older sellers used to call long-term storage fees). The 2026 schedule (effective Jan 16, 2026) starts at $0.50/cu ft/month at 181 days and climbs in tiers, jumping sharply to $5.45/cu ft at 271 days. Past 366 days, Amazon also assesses a per-unit minimum ($0.30 at 366+, $0.35 at 456+) and bills the greater of the per-cu-ft rate or the per-unit minimum.
When does Amazon actually assess the aged inventory surcharge?
Amazon takes an inventory snapshot on the 15th of each calendar month. The age of each unit on that snapshot date determines the tier, and that month's surcharge is billed against the units in FBA on the 15th. If your stock is gone before the 15th, no aged surcharge for that month. This calculator models that snapshot logic directly, so its month-by-month aged column lines up with how Seller Central charges you.
My unit is small. Will the per-unit minimum apply to me at 366+ days?
Almost always, yes. The 366+ tiers compare two numbers and bill whichever is greater: (unit cu ft × $6.90 or $7.90) vs. (per unit × $0.30 or $0.35). Small lightweight items — anything under about 0.04 cu ft / ~70 cu in for the 366+ tier — hit the per-unit minimum first. That's why a tiny accessory aged 1+ year can cost more to store than its landed cost.
How accurate is this estimate?
Good enough to size up a single PO. The math uses Amazon's published 2026 U.S. rate schedule for base monthly storage and the aged inventory surcharge schedule, with the surcharge assessed against the 15th-of-month snapshot the way Amazon does. Real bills can still vary based on which fulfillment regions store your units, fee waivers Amazon runs, dimensional rounding on your ASIN, and any account-level fees outside this calculator's scope — storage utilization surcharge, storage overage fees, low-inventory-level fees, inbound placement service fees, removal/disposal, and special-program exceptions. Always confirm in Seller Central before treating any number as final.
What does this calculator NOT include?
It estimates the two storage charges most sellers care about — base monthly inventory storage and the aged inventory surcharge — and intentionally leaves the rest out. Specifically, it does not include: (1) the storage utilization surcharge (based on your IPI and how long inventory has been sitting on average), (2) storage overage fees (assessed when you exceed your allocated FBA capacity), (3) low-inventory-level fees, (4) inbound placement service fees, (5) removal, disposal, and returns processing fees, and (6) special-program exceptions, hazmat storage, apparel-specific tiers, and other category-specific rate cards — these all bill differently from the standard-size and large bulky / oversize tiers this calculator models. For a full account-level view, use Seller Central's Storage Fee report and the Aged Inventory Surcharge report.
What happens if I order so much that some inventory ages past 271 days?
The aged surcharge jumps from $1.50/cu ft to $5.45/cu ft — roughly 3.6× — and keeps climbing through 300, 330, and 365 days. Past 366, the per-unit minimum kicks in on top (whichever is greater of cu-ft rate vs. per-unit). For most categories, this is the point where carrying the unit costs more than discounting it heavily or removing it. If your sell-through projects past 271 days, plan a velocity push or removal before you hit it.
Does this cover dangerous goods, apparel, or other special-handling tiers?
No. This calculator covers the two main FBA size tiers — standard-size and large bulky / oversize — which roughly cover 75% of Amazon catalogs. Dangerous goods, apparel-specific tiers, and certain special-handling categories have their own rate cards and bill differently. For those SKUs, verify the tier and rates in Seller Central before relying on this estimate.
Should I store excess inventory in AWD or a 3PL instead?
Often, yes — for stock you don't expect to sell in the next 60–90 days. AWD and 3PLs both bill by cubic foot but at lower rates than peak FBA, and neither has Amazon's aged inventory surcharge tiering. The trade-off is the transfer cost and lead time to top up FBA from AWD/3PL. The AWD vs FBA vs 3PL Storage Estimator runs that math.
Do I need to enter cubic inches precisely?
For ballpark planning, no. For purchasing decisions, yes. Storage fees scale linearly with cubic feet, so a 20% volume error becomes a 20% fee error. Use Amazon's actual dimensions from the ASIN (length × width × height in inches, then divided by 1728 to get cubic feet) rather than your packaging spec, since Amazon measures the finished unit.
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▲ Profit Hawk

Want this tracked automatically across all your Amazon SKUs?

Profit Hawk recalculates FBA storage cost exposure — base, peak, and aged — using your real Amazon inventory and sales data, across every SKU and every marketplace.

Start free trialSee Profit Hawk