Profit Hawk
Free tool · For Amazon FBA sellers

AWD vs FBA vs 3PL Storage Estimator
for Amazon sellers.

Compare the real, all-in cost of storing extra Amazon inventory in FBA, AWD, or a 3PL — and get a placement recommendation tied to your sell-through speed.

?
What question does this answer
“Should I store this extra Amazon inventory in FBA, AWD, or a 3PL?”
1

Inventory you're placing

Tell us how much, how big, and how long you expect it to sit.

units
ft³
months
units / mo

Storage horizon is how long the units will likely sit before they sell. If you're not sure, divide your planned units by your monthly sales velocity.

Recommended placement
Stage at AWD

AWD comes out cheapest over your horizon. Use it for overflow and let Amazon handle replenishment into FBA as you sell through.

Estimated cost over horizonEstimate

Based on 1,000 units at 0.4 ft³ each, sitting for 3 months — at your entered rates.

Months of cover
3.3months
Cheapest option
Amazon AWD
2

Storage rates & fees (your assumptions)

Amazon AWD fees changed in 2026 and rates vary by season and provider. Plug your own numbers in — verify the live schedule in Seller Central before committing.

FBA
$ / ft³

Vary by month and category. Off-peak rates are lower than Q4 peak rates.

Amazon AWD
$ / ft³
$ / unit
$ / unit
3PL
$ / ft³
$ / unit
$ / unit
3

Cost comparison

Total cost across your storage horizon, by placement.

Amazon FBA
$2,640
total over 3 months
Monthly storage
$880.00
Storage subtotal
$2,640.00
Processing & transfer
$0.00
Cost per unit
$2.64
Cheapest
Amazon AWD
$1,300
total over 3 months
Monthly storage
$200.00
Storage subtotal
$600.00
Processing & transfer
$700.00
Cost per unit
$1.30
3PL warehouse
$1,640
total over 3 months
Monthly storage
$480.00
Storage subtotal
$1,440.00
Processing & transfer
$200.00
Cost per unit
$1.64

Cost numbers are estimates based on the rates you entered above. Cheapest doesn't always equal "best" — for near-term sell-through, the transfer-and-handling fees on AWD or 3PL can outweigh the storage savings. Use the recommendation in Step 1 as the operational call.

How it works

The method, in plain English.

For each option, multiply cubic feet by storage rate by months, then add per-unit fees. Compare the totals. Adjust the recommendation for your sell-through speed.

Total cost =ft³ ×rate ×months +per-unit fees
FBA
Premium fulfillment storage. Higher monthly storage cost but no transfer or processing fees. Best for near-term sell-through (≤6 weeks). Aged-inventory surcharges apply past 180 days.
AWD
Amazon's upstream bulk storage. Lower per-cubic-foot rates than FBA, but adds processing and transportation fees when units move into FBA. Built for overflow that you expect to replenish into FBA over time.
3PL
Third-party warehouse. Storage cost varies by provider. Wins when you need kitting, returns processing, multi-channel fulfillment, or when AWD's processing fees outweigh its storage savings.
↦ FBA
The transfer math nobody mentions. Anything stored outside FBA has to get to FBA eventually — and that move isn't free. Per-unit transportation (AWD) and outbound shipping (3PL) often decide which option actually wins.

Worked example

1,000 units at 0.5 ft³ each — 3 months of expected cover.

Total cube500 ft³
FBA storage (3 mo × $2.20)$3,300
AWD storage (3 mo × $0.50)$750
AWD processing + transport (1,000 × $0.70)$700
AWD total$750 + $700 = $1,450
3PL storage + handling$1,500 + $200 = $1,700
Cheapest
Amazon AWD — $1,450

Numbers are an illustration — Amazon's AWD rates changed in 2026, so verify the live schedule in Seller Central before committing.

Watch out for

Common placement mistakes.

Placement decisions look like cost optimization but are mostly assumption hygiene. These are the patterns we see most.

01

Comparing only the storage rate

AWD's per-cubic-foot rate looks dramatic next to FBA — but AWD adds processing and transportation per unit. For a short sell-through horizon, those fees can easily flip the math.

Fix: Always compare total cost over your storage horizon, not just the monthly storage rate.
02

Forgetting the transfer fee on the way to FBA

Anything in AWD or a 3PL eventually has to get to an FBA fulfillment center — and that move isn't free. Skipping that line item makes overflow storage look cheaper than it really is.

Fix: Include AWD's transportation fee, your 3PL's outbound rate, and any extra freight or labeling in the per-unit fees row.
03

Storing slow movers in FBA because they fit

Capacity availability isn't a placement strategy. Sending a slow mover to FBA because you have the cube available just trades one cost (lost margin) for two (storage + aged surcharge).

Fix: If days of cover exceeds 90–120 days, route to AWD or a 3PL and pull to FBA on demand.
04

Treating 6+ months of cover as just a storage problem

When you're sitting on a year of inventory, picking the cheapest warehouse misses the point. The problem is upstream — too much was ordered, the SKU isn't selling, or the launch underperformed.

Fix: Run the Aged Inventory Risk Calculator first. Don't optimize storage for inventory that shouldn't exist yet.
05

Modeling with last quarter's AWD rates

Amazon has updated AWD pricing more than once. Using stale assumptions makes AWD look more — or less — attractive than it is today.

Fix: Refresh the storage and processing rates before any sizable placement decision. Verify in Seller Central.
06

Picking on cost alone for hero SKUs

Your top SKUs benefit from FBA's fast delivery promise. Saving $0.20/unit on storage doesn't make up for ranking damage if the SKU misses Prime-fast windows.

Fix: Default A-tier SKUs to FBA. Optimize AWD/3PL placement for B and C tiers.
When this calculator isn't enough

Great for one decision.
Harder across a real catalog.

Deciding where one SKU should sit is a 60-second question once you have the rates. Deciding it for every SKU, every week, with rate changes and velocity drift — that's a different job.

  • Real per-SKU storage horizonsCover varies SKU by SKU. A blanket 'send to AWD' rule overstocks fast movers and understocks slow ones.
  • Multiple storage rate tiersFBA storage changes by month, category, and how long units have been in. Modeling a single rate misses the cost curve.
  • AWD fee updatesAmazon adjusts AWD fees periodically. Your model needs to follow them without anyone re-pasting a fee table.
  • 3PL contracts changePer-cubic-foot, handling, and outbound rates differ by 3PL and shipping volume. Models go stale fast.
  • Cross-storage cover mathReplenishment decisions depend on the combined FBA + AWD + 3PL + inbound view, not any one of them alone.
  • Aged-inventory exposureSome placements minimize storage cost but increase aged-inventory risk. The trade-off needs both lenses.
▲ Profit Hawk

Make placement decisions automatically, SKU by SKU.

Profit Hawk continuously compares FBA, AWD, and 3PL economics using your real sell-through, real cube, and current rates — and recommends where each incoming PO should sit.

  • Per-SKU FBA / AWD / 3PL recommendation
  • Auto-updates on Amazon AWD rate changes
  • Combined FBA + AWD + 3PL cover math
  • Aged-inventory-aware placement
Start free trialSee Profit Hawk →
FAQ

AWD, FBA, and 3PL, answered.

The questions Amazon sellers actually ask us about placement, AWD rate changes, and when a 3PL beats sending more to FBA.

What is AWD and how is it different from FBA?
Amazon Warehousing & Distribution (AWD) is Amazon's bulk storage service. It typically charges lower per-cubic-foot storage rates than FBA but adds processing and transportation fees when units move to FBA fulfillment centers. AWD is positioned as overflow/upstream storage that feeds FBA — not as a replacement for FBA fulfillment.
Does this tool know the current AWD or FBA storage rates?
No, and deliberately so. Amazon AWD fees changed substantially in 2026 and rates continue to evolve, with multiple fee components (storage, processing, transportation) that vary by season and shipment size. Every rate field is editable — pull the current numbers from Seller Central or your AWD/3PL invoice before you commit to a decision.
When should I send extra inventory to FBA versus AWD?
As a rule of thumb: if you'll sell through the inventory inside about six weeks, send it straight to FBA — the storage savings on AWD usually don't offset the per-unit transfer fees over a short horizon. If you expect 2–6 months of cover, AWD is typically the cheapest staging spot. If it's more than 6 months of cover, you probably shouldn't be sending it to Amazon at all — that's a 3PL conversation, not an FBA one.
When does a 3PL win over AWD?
3PLs usually win when you need flexibility AWD doesn't give you — kitting, custom packaging, returns processing, multi-channel fulfillment, or when AWD's processing/transportation fees outweigh its storage savings for your size profile. They can also win on slow movers where every dollar of monthly storage matters.
What does 'storage months' mean exactly?
It's how long you expect those units to sit before they sell. The simplest way to estimate it is units ÷ monthly sales velocity. The tool uses that number to project cost — and uses your monthly sales velocity (optional) to override the recommendation if you've entered way more inventory than you can sell through.
Should I include the transfer-to-FBA cost twice if it's in AWD's transportation fee?
No. The 'extra transfer to FBA' field at the bottom is for cases where you haven't already captured the transfer in AWD's transportation fee — for example, if you're modeling a 3PL placement that doesn't include FBA replenishment in its base rate. If your AWD transportation fee already covers the FBA transfer, leave the extra field blank.
Why is the cheapest option not always the recommended one?
Because operational reality matters more than spreadsheet math for short horizons. If you'll sell out in four weeks, paying a little more for FBA storage and skipping AWD's processing-plus-transfer fees usually nets out cheaper — and saves you a transit window. The recommendation in Step 1 takes horizon and velocity into account; the comparison cards in Step 3 are pure cost.
Can I use this for non-Amazon storage decisions too?
You can use the 3PL math for any external warehouse, but this tool is opinionated around the Amazon ecosystem — the recommendation assumes you'll ultimately fulfill via FBA. For pure direct-to-consumer 3PL comparisons that don't touch FBA, the per-unit transfer cost should be 0 and you can ignore the AWD column.
Free tools

More for Amazon sellers.

Inventory

FBA Capacity Usage Calculator

See how much of your Amazon FBA storage capacity is used and whether your next shipment will fit.

Open calculator →
Inventory

Aged Inventory Risk Calculator

Project how much FBA stock is heading for the aged-inventory surcharge.

Open calculator →
All tools

Browse all free tools

Calculators for safety stock, reorder points, capacity, aged inventory, and more.

Open calculator →
▲ Profit Hawk

Want placement automated across FBA, AWD, and your 3PL?

Profit Hawk continuously decides where each SKU should sit based on real sell-through, current rates, and aged-inventory risk — so you stop eyeballing it on every PO.

Start free trialSee Profit Hawk