Amazon FBA Inventory Management: Health and Fees

Amazon stopped charging FBA (Fulfillment by Amazon) inventory storage overage fees on July 1, 2024 in the US, Europe, UK, and Canada stores. Inventory health is now four separate checks: cubic-foot capacity by storage type, monthly storage cost, units nearing the 181-day aged-inventory threshold, and SKUs running lean enough to trigger the low-inventory-level fee.

An agent runs that review through the Amazon Selling Partner MCP, reading Amazon's inventory planning, storage-fee, and aged-inventory reports. Amazon Agent Atlas grounds each rule in Amazon's help pages, so the policy windows and report fields are not guessed. No published Kuudo Skill covers the whole review, so the ranking rules live in a Skill your team writes.

ChatGPT, Claude, Perplexity, Microsoft Copilot, and whatever comes next know nothing about your business out of the box, and your competitors use them too. Kuudo gives them your data, your rules, and the way your business operates. The Selling Partner MCP reads current FBA inventory, the Amazon Ads MCP can add demand context by Amazon Standard Identification Number (ASIN), your Skill ranks the risk, and your workspace policy may require approval before anything changes.

Atlas separates the fee that ended from the fees still charged

The first move is a policy check, not a removal list. Amazon stopped charging FBA inventory storage overage fees in the named stores from July 1, 2024, as announced by its VP of Selling Partner Services.

Its FBA fees overview still lists the overage fee, so read the capacity limits page for the current consequence. Its FBA capacity limits page now gives a different consequence for going over: if on-hand inventory plus shipments on the way exceed your limit, you're blocked from creating new shipments to Amazon.

Everything else still bills. Atlas returns Amazon's current fee pages, so the agent does not collapse "overage fee removed" into "storage is free":

• Monthly inventory storage fee, charged on your daily average volume in cubic feet, plus a storage utilization surcharge for sellers who meet Amazon's criteria.
• Aged inventory surcharge, on units stored 181 days or longer, charged in addition to the monthly fee.
• Low-inventory-level fee, added per unit shipped when both short- and long-term historical days of supply fall below 28.
• Capacity Manager reservation fee, only if you request extra capacity and Amazon grants it. Performance credits on sales from that capacity can offset it.

The output is a short policy record: store, effective dates, fee families in play, and the Amazon help page behind each one. Every later recommendation cites it.

The Selling Partner MCP measures capacity in cubic feet, by storage type

Capacity is a volume problem. Amazon sets one limit per storage type per month (standard-size, oversize, apparel, footwear, extra-large, and for Dangerous Goods sellers, flammable and aerosol), measured in cubic feet, and capacity can't be exchanged between storage types. Capacity Manager can't request more space for the Dangerous Goods types. A few bulky units can create the constraint while the unit count looks flat.

The agent reads per-SKU volume from GET_FBA_INVENTORY_PLANNING_DATA through the Selling Partner MCP: storage-type, storage-volume, item-volume, and volume-unit-measurement. Amazon defines storage-volume as the product's total usage in fulfillment centers minus inventory pending removal.

The limit itself sits in the Capacity Monitor at the bottom of the FBA dashboard, which the MCP does not expose, so the seller supplies it. Open shipments count toward usage, so they belong in the check:

capacity_check:
  storage_type: oversize
  capacity_limit_cu_ft: 500      # from Capacity Monitor
  storage_volume_cu_ft: 470      # sum of storage-volume, planning report
  open_shipments_cu_ft: 60       # inbound shipments count toward usage
  headroom_cu_ft: -30
  status: new shipments blocked for this storage type
  decision: rank slow-moving bulky SKUs by cubic-foot contribution

The historical GET_FBA_OVERAGE_FEE_CHARGES_DATA report still documents storage_usage_volume, storage_limit_volume, overage_volume, and volume_unit for past overage charges. Treat it as history, not as today's limit.

The agent reads IPI as a signal, then diagnoses the ASINs behind it

Amazon's Inventory Performance Index (IPI) measures how efficient and productive you are in managing FBA inventory over time. It still matters for capacity: Amazon says your limit is influenced by your IPI score, alongside sales forecasts, seasonality, shipment lead time, and fulfillment center capacity. It does not name the action for a specific ASIN.

Amazon groups its IPI recommendations into four categories. The agent keeps the parts behind the score and joins them to cost and timing evidence:

Amazon Agent Flow lands the report data in a lake you own on a schedule, with each report's window attached. The same foundation supports a weekly health review, an aged-inventory cleanup, or a replenishment workflow without rebuilding the data for each one.

The decision queue names the affected ASIN, the signal that changed, the source report, and the first reversible action to review. A falling IPI score can trigger the workflow. It should not become an instruction to cut inventory across the account.

The Selling Partner MCP reads storage cost and aged-inventory exposure

Storage cost has two layers, and each has its own report. The agent reads both through the Selling Partner MCP and keeps them apart from capacity.

Monthly storage and the utilization surcharge

Base monthly storage is charged on daily average cubic feet. Amazon's current off-peak rate (January to September) is $0.78 per cubic foot for standard-size and $0.56 for oversize, and the peak rate (October to December) is $2.40 and $1.40. Dangerous goods use higher rates.

The storage utilization surcharge adds to that when all four of Amazon's criteria hold: a Professional account, a first US fulfillment center shipment more than 365 days ago, at least 25 cubic feet of average daily volume for the size tier, and a storage utilization ratio above 22 weeks. It applies only to inventory aged above 30 days.

The ratio is stored volume divided by shipped volume over 13 weeks, shown on the FBA dashboard. Products auto-replenished through Amazon Warehousing and Distribution (AWD) can earn a surcharge waiver, and FBA New Selection units on free storage are left out. GET_FBA_STORAGE_FEE_CHARGES_DATA gives estimated_monthly_storage_fee and storage_rate per ASIN.

Aged inventory before the fifteenth-day snapshot

The aged inventory surcharge applies to units stored 181 days or longer, assessed on an inventory snapshot on the fifteenth of each month. Amazon counts age first-in, first-out across the network. Since January 16, 2026, units aged 366 to 455 days pay $6.90 per cubic foot or $0.30 per unit, whichever is greater, and 456 days or more pay $7.90 or $0.35.

GET_FBA_INVENTORY_PLANNING_DATA carries the pre-snapshot view: age buckets plus quantity-to-be-charged-ais-* and estimated-ais-* columns by age band. The agent sorts by days to threshold, cubic-foot exposure, and the removal deadline:

as_of: 2026-10-01
next_snapshot: 2026-10-15
removal_order_deadline: 2026-10-14 23:59 PT
asin: B0EXAMPLE12
age_days: 170
age_at_snapshot: 184
per_unit_volume: 0.102 cubic feet
review: removal, disposal, Outlet deal, or sell-through economics

A removal or disposal order submitted by 11:59 p.m. PT on the 14th keeps those units out of the surcharge, even if they have not left the building. The Selling Partner API has no operation for creating removal orders, so the agent drafts the list and you file it in Seller Central.

After the charge, GET_FBA_FULFILLMENT_LONGTERM_STORAGE_FEE_CHARGES_DATA itemizes it: qty-charged, per-unit-volume, surcharge-age-tier, rate-surcharge, and amount-charged. Keep it beside the pre-snapshot queue to compare the avoided cost with the action you chose.

The Stockout Prevention Skill watches the low-inventory-level fee

Cutting stock to save storage has a floor. The low-inventory-level fee applies when both long-term (last 90 days) and short-term (last 30 days) historical days of supply are below 28 days. Amazon adds it to the fulfillment fee for every unit shipped, and since January 15, 2026 it is calculated per seller FNSKU (Fulfillment Network Stock Keeping Unit) and covers Small and Large Bulky products.

Some SKUs are exempt:

• New Professional sellers, for the first 365 days after the first inventory-received date.
• Products that sold fewer than 20 units in the past 7 days.
• SKUs with 70% or more of inventory auto-replenished through AWD over the prior 90 days.
• New-to-FBA parent products enrolled in FBA New Selection, for their first 180 days.
• The Grocery category.

The planning report shows historical-days-of-supply, Short term historical days of supply, Long term historical days of supply, Exempted from Low-Inventory-Level fee?, and Low-Inventory-Level fee applied in current week?. The published Stockout Prevention Skill reads that report, flags the fee, and changes nothing. Pair it with your storage review so one fee is never traded blindly for another.

What happens next: run the review on a schedule, policy check first

Run the review on a schedule: policy check first, then capacity by storage type, monthly storage, the aged-inventory countdown before the 14th, and the low-inventory floor last. The agent returns one report with the source help pages, report fields, affected SKUs, and proposed actions.

A person then acts on it:

• Removal, disposal, and liquidation orders are filed in Seller Central.
• Replenishment shipments can run through the Selling Partner MCP's Fulfillment Inbound operations, which the published FBA inbound Skill walks step by step, and your workspace policy may require approval.
• Each run's data stays in your lake through the Amazon Agent Data layer, so the next review starts from the last one.

If your FBA review still asks only whether the overage fee exists, it is reading one policy line instead of inventory health. Separate volume, storage, age, and the low-inventory floor, then decide with the evidence in front of you.

Next: why units go Reserved, and when a whole-ASIN reserve may be a recall with a 30-day removal window, in Amazon FBA Reserved Inventory.