Definition
Long-term storage fees encompass every storage-related charge that accumulates when FBA inventory sits unsold for extended periods. This includes two distinct cost layers: the regular monthly storage fee that applies to all inventory from day one, and the aged inventory surcharge that kicks in after 180 days.
The distinction matters because many sellers only watch the surcharge and ignore the compounding monthly fees underneath it. A unit that takes six months to sell has already accumulated $4.68 per cubic foot in regular storage fees (6 × $0.78) before any surcharge applies. Add Q4 rates and the math gets worse fast.
For standard-size products, Amazon charges storage per cubic foot based on volume (length × width × height ÷ 1,728). The cubic footage determines both your regular monthly bill and your surcharge exposure. Oversized products actually pay a lower per-cubic-foot rate ($0.56 vs $0.78), but their larger volume means the total dollar amount is often higher.
2026 long-term storage fee rates
Monthly storage fees (all inventory)
| Size tier | Jan–Sep | Oct–Dec |
|---|---|---|
| Standard-size | $0.78 / cu ft | $2.40 / cu ft |
| Oversize | $0.56 / cu ft | $1.40 / cu ft |
Aged inventory surcharge (on top of monthly fees)
| Inventory age | Surcharge / cu ft | Per 0.15 cu ft unit |
|---|---|---|
| 0–180 days | $0.00 | $0.00 |
| 181–270 days | $0.50 | $0.08 |
| 271–365 days | $5.45 | $0.82 |
| 365+ days | $6.90 (or $0.30/unit) | $1.04 (or $0.30) |
Example: 50 unsold units sitting for 11 months
50 units of a standard-size product, each 0.2 cu ft (10 × 7 × 5 inches). Total volume: 10 cu ft. Product cost: $6 per unit ($300 total invested). Sent to FBA on January 1. None sell.
| Period | Rate breakdown | Cost |
|---|---|---|
| Jan–Jun (months 1–6) | 10 cu ft × $0.78 × 6 | $46.80 |
| Jul–Sep (months 7–9, day 181+) | 10 cu ft × ($0.78 + $0.50) × 3 | $38.40 |
| Oct–Nov (months 10–11, day 271+, Q4) | 10 cu ft × ($2.40 + $5.45) × 2 | $157.00 |
| Total storage cost (11 months) | $242.20 | |
| % of inventory value | 80.7% |
In under a year, storage fees consumed 81% of the inventory value. If these units sit through December and into January (past 365 days), the rate jumps to $6.90 per cubic foot plus $0.78 monthly, adding another $76.80 per month. At that point, the removal order at $0.97 per unit ($48.50 total) is dramatically cheaper than one more month of storage.
Why long-term storage fees compound faster than expected
Two cost curves collide at the worst possible time. Q4 storage rates triple from $0.78 to $2.40 per cubic foot in the exact months when aged inventory crosses the 271-day surcharge threshold (if sent in January). The combined rate of $7.85 per cubic foot ($2.40 + $5.45) is 10× the base rate of $0.78. This hockey-stick cost curve catches sellers who treat storage as a rounding error.
For excess inventory, Amazon Warehousing and Distribution (AWD) charges a flat $0.56 per cubic foot with no aged surcharge, regardless of how long units sit. Staging slow-moving inventory in AWD and drip-feeding to FBA as needed avoids both the surcharge tiers and the Q4 rate spike. The tradeoff is longer replenishment lead times, which requires tighter demand forecasting.
Common mistakes
- Only tracking the aged surcharge, ignoring regular monthly storage. Monthly fees at $0.78 per cubic foot accumulate from day one. On 10 cu ft of inventory, that is $7.80 per month or $70.20 in the first six months before any surcharge applies.
- Sending excess inventory before Q4. Storage rates triple from October through December. Sending six months of supply in September means paying $2.40 per cubic foot on units that will not sell until December or January. Stage excess in AWD or a 3PL and replenish weekly.
- Not factoring storage into per-unit profitability. Storage cost per unit depends on sell-through velocity. A product that turns in 30 days costs $0.04 per unit in storage. The same product turning in 120 days costs $0.16. That difference matters at scale.