Key Takeaways
- →Amazon FBA storage fees are $0.87/cu ft (standard, Jan–Sep) and $2.40/cu ft (peak, Oct–Dec) for standard-size items — a 2.75× increase during Q4.
- →Monthly storage fee = Units × Cubic Feet per Unit × Seasonal Rate. The calculator auto-fills the rate based on season selection.
- →Long-term storage fees of $6.90/cu ft apply to items aged 271+ days, and $13.81/cu ft for items aged 365+ days — charged in addition to monthly fees.
- →Cubic feet = (L × W × H in inches) ÷ 1,728. A 12×10×8 inch box = 0.556 cu ft, costing $0.48/month at standard rate or $1.33/month at peak rate.
- →Sellers who let inventory age past 271 days can pay more in long-term storage fees than the product is worth — monitor inventory age weekly.
Amazon Storage Fee Calculator: Monthly and Long-Term FBA Storage Costs
Storage fees are the silent profit killer on Amazon FBA. While referral and fulfillment fees are deducted per sale, storage fees accrue every month whether your products sell or not. A product that sits in Amazon's warehouse for 6 months can accumulate more in storage fees than the profit from the units that do sell. The Amazon storage fee calculator on this page estimates your monthly storage costs and reveals the impact of Q4 peak rates — which nearly triple compared to the rest of the year.
- How the Storage Fee Calculator Works
- Amazon Storage Fee Rates by Season
- Calculating Cubic Feet
- Long-Term Storage Fees
- Worked Examples
- How to Reduce Storage Fees
- Frequently Asked Questions
How the Storage Fee Calculator Works
The calculator takes four inputs and computes the monthly storage fee:
Monthly Storage Fee = Units × Cubic Feet per Unit × Seasonal Rate
Inputs:
- Units Stored — the number of units currently in Amazon's warehouse
- Cubic Feet per Unit — the volume of one unit in cubic feet (see calculation below)
- Season — select Standard (Jan–Sep, $0.87/cu ft) or Peak (Oct–Dec, $2.40/cu ft); the rate auto-fills
- Rate ($/cu ft) — auto-filled from the season selector, but can be overridden for custom scenarios
The calculator returns the total monthly storage fee and the per-unit monthly cost.
Amazon Storage Fee Rates by Season
Amazon charges storage fees based on the time of year, with dramatically higher rates during Q4 to incentivize sellers to keep inventory moving.
Monthly storage rates (per cubic foot):
| Period | Standard-Size | Oversize | Ratio vs. Standard |
|---|---|---|---|
| January–September | $0.87 | $0.56 | 1× |
| October–December | $2.40 | $1.40 | 2.76× (standard), 2.50× (oversize) |
The Q4 peak rate is 2.76× higher than the standard rate for standard-size items. This means inventory sitting in Amazon's warehouse during October–December costs nearly three times as much per month. Amazon implemented this tiered pricing to discourage sellers from using FBA warehouses as long-term storage during the holiday shipping rush.
Why oversize rates are lower per cubic foot: Oversize items take up proportionally less warehouse management overhead per cubic foot compared to the dense shelving used for standard-size items. However, oversize items occupy much more total volume, so the dollar cost per unit is typically higher.
Calculating Cubic Feet
To calculate the cubic feet of a single unit:
Cubic Feet = (Length × Width × Height in inches) ÷ 1,728
The division by 1,728 converts cubic inches to cubic feet (12³ = 1,728).
Common product volume examples:
| Product Dimensions (inches) | Cubic Feet | Standard Monthly Fee | Peak Monthly Fee |
|---|---|---|---|
| 6 × 4 × 2 | 0.028 | $0.02 | $0.07 |
| 10 × 8 × 4 | 0.185 | $0.16 | $0.44 |
| 12 × 10 × 6 | 0.417 | $0.36 | $1.00 |
| 12 × 10 × 8 | 0.556 | $0.48 | $1.33 |
| 18 × 14 × 10 | 1.458 | $1.27 | $3.50 |
| 24 × 18 × 12 | 3.000 | $2.61 | $7.20 |
Tip: Use the product's packaged dimensions (including Amazon's FBA packaging), not the product's bare dimensions. Amazon measures the package, not the product inside.
Long-Term Storage Fees
In addition to monthly storage fees, Amazon charges long-term storage (LTS) fees on inventory that has been in fulfillment centers for extended periods.
Long-term storage fee rates:
| Age Threshold | Fee Rate | Assessment Date |
|---|---|---|
| 271+ days | $6.90/cu ft | 15th of each month |
| 365+ days | $13.81/cu ft | 15th of each month |
LTS fees are charged IN ADDITION to the regular monthly storage fee. An item aged 300 days occupying 0.5 cu ft costs:
- Monthly storage: 0.5 × $0.87 = $0.44
- LTS fee: 0.5 × $6.90 = $3.45
- Total that month: $3.89 — nearly 9× the standard monthly rate
The LTS trap: A product that cost $5 to source and sells for $15 with $8 in fees (leaving $2 profit) can accumulate $3.89/month in storage + LTS fees. After just 2 months of LTS charges, the storage cost exceeds the product's profit. After 6 months, the storage cost exceeds the product's cost — you're paying Amazon more to store the product than it cost to make.
Avoiding LTS fees:
- Monitor inventory age weekly via Seller Central's Inventory Health report
- Submit removal orders for items approaching 270 days before the 15th of the month
- Run clearance sales or PPC campaigns to move aging inventory
- Use the Seasonal Storage strategy: send smaller, more frequent shipments rather than one large bulk order
Worked Examples
Example 1: Standard-size product, 500 units
A seller stores 500 units of a kitchen product measuring 10×8×4 inches.
Cubic feet per unit: (10 × 8 × 4) ÷ 1,728 = 320 ÷ 1,728 = 0.185 cu ft Standard monthly fee: 500 × 0.185 × $0.87 = $80.48 Peak monthly fee: 500 × 0.185 × $2.40 = $222.00
Use the calculator: enter 500 units, 0.185 cu ft, Standard season → $80.48/month.
Example 2: Q4 peak season impact
The same 500 units stored during October–December (3 months):
Standard period (3 months at $0.87): 3 × $80.48 = $241.44 Peak period (3 months at $2.40): 3 × $222.00 = $666.00 Additional Q4 cost: $666.00 − $241.44 = $424.56
The Q4 peak adds $424.56 in storage costs for the same inventory. If this product has a $2 per-unit margin, the seller needs 212 additional sales just to cover the peak storage premium.
Example 3: Long-term storage penalty
A seller has 200 units of a slow-selling product (12×10×8 inches) that have been in Amazon's warehouse for 280 days.
Cubic feet per unit: (12 × 10 × 8) ÷ 1,728 = 0.556 cu ft Monthly storage: 200 × 0.556 × $0.87 = $96.74 LTS fee (271+ days): 200 × 0.556 × $6.90 = $767.28 Total monthly cost: $96.74 + $767.28 = $864.02
The LTS fee is 8× the regular storage fee. If the product sells for $25 with $8 margin, the seller needs 108 sales/month just to break even on storage — clearly unsustainable.
Example 4: Optimizing shipment frequency
A seller can send 1,000 units once or 250 units quarterly. Product: 10×8×4 inches (0.185 cu ft), sells 80 units/month.
Option A — one shipment of 1,000 units:
- Months 1–3: 1,000 units → $80.48 × 3 = $241.44
- Months 4–6: 760 units (avg) → ~$61 × 3 = $183
- Months 7–9: 520 units (avg) → ~$42 × 3 = $126
- Months 10–12: 280 units (avg) → ~$23 × 3 = $69
- Year 1 total: ~$619 (plus risk of LTS fees on units aged 271+ days)
Option B — quarterly shipments of 250 units:
- Each quarter: 250 units for 3 months → $80.48 + ~$53 + ~$27 = ~$161 per quarter
- Year 1 total: ~$644 (but NO LTS risk, as inventory turns over every ~3 months)
Option A is slightly cheaper if no LTS fees trigger, but Option B eliminates LTS risk entirely. The calculator helps model these scenarios.
How to Reduce Storage Fees
1. Optimize packaging: Smaller packaging = lower cubic feet = lower fees. Redesigning a box from 12×10×8 to 10×8×6 reduces volume by 40%, saving 40% on storage.
2. Increase inventory turnover: Faster-selling products spend less time in the warehouse. Focus on products with high demand and competitive pricing.
3. Send smaller, more frequent shipments: Rather than one large order, send quarterly batches sized to sell out in 90 days. This keeps inventory age below the 271-day LTS threshold.
4. Clear aging inventory proactively: Submit removal orders for items approaching 270 days. Selling via liquidation or eBay may recover more value than paying LTS fees.
5. Use FBA for fast-movers, FBM for slow-movers: Move slow-selling products to Fulfilled by Merchant (FBM) to avoid FBA storage fees entirely, accepting higher per-order fulfillment costs.
6. Monitor the Inventory Health report: Check weekly for items approaching age thresholds. Amazon's Sell-Through and Stranded Inventory reports identify problems before they become costly.