Amazon Fulfillment Centers: How They Work, What They Cost, and What Changed in 2026

Table of Contents

• What Is an Amazon Fulfillment Center?
• How Fulfillment Centers Process Your Orders
• Amazon’s Fulfillment Network in 2026
• FBA Storage Fees: What You Actually Pay
• Aged Inventory Surcharges: The Cost of Sitting Still
• 2026 Fulfillment Center Changes That Affect Your Operations
• How Fulfillment Center Assignment Affects Your Costs
• FAQ

What Is an Amazon Fulfillment Center?

Most sellers think of fulfillment centers as warehouses. That undersells what they are and overstates what you control about them.

An Amazon fulfillment center is a large-scale logistics facility where Fulfillment by Amazon (FBA) inventory is stored, picked, packed, and shipped. These facilities handle everything from receiving your inbound shipments to processing customer returns. When a buyer places an order, the fulfillment center closest to the delivery address with the item in stock handles the shipment - which is why Amazon splits your inventory across multiple locations rather than storing it all in one place.

You don’t choose which fulfillment center holds your products. Amazon makes that decision based on product size, category, demand forecasting, and proximity to buyer clusters. This matters more than most sellers realize, because the facility your product lands in determines your storage cost region, your delivery speed to nearby buyers, and how quickly Amazon can route your inventory when demand shifts.

How Fulfillment Centers Process Your Orders

Behind the automation - the robots, the packing algorithms, the sorting lines - three cost levers affect your margin on every order.

First, packaging: Amazon selects items, packs them in optimized packaging, and labels for shipping. Products that qualify for Ships in Product Packaging (SIPP) skip Amazon’s additional packaging and earn an automatic fee discount on standard items as of 2026 - that alone can save $0.20-$0.40 per unit on the packaging component. Second, carrier routing: orders flow through Amazon’s growing air and ground fleet, with Prime orders getting priority handling. Third, returns triage: FBA returns flow back through the fulfillment center network, where Amazon inspects and either restocks or moves them to unsellable status. Slow restock means phantom out-of-stock, which costs you the Buy Box while the unit sits in limbo.

Once your inventory enters the fulfillment center, Amazon controls the speed, packaging, and customer experience. You give up operational control in exchange for Prime eligibility and Amazon’s delivery infrastructure - and for most sellers above 200 units/month, that trade-off still pencils out.

Amazon’s Fulfillment Network in 2026

Amazon now operates over 110 fulfillment centers in the United States alone, plus hundreds more globally - sortation centers, delivery stations, air hubs. The footprint has more than doubled since 2020.

A denser network means faster delivery times, which helps your conversion rate and Buy Box competitiveness. But it also means Amazon is more likely to distribute your inventory across multiple facilities to optimize last-mile delivery - and that distributed inventory affects how you think about inbound shipping, storage utilization, and removal orders. On replenishments over 1,000 units, plan for 3-5 destination facilities per ASIN; that split is now the default, not the exception.

FBA Storage Fees: What You Actually Pay

Storage fees are where most sellers underestimate their fulfillment center costs. The per-unit fulfillment fee gets the attention, but storage fees compound monthly and spike in Q4. As of early 2026, monthly inventory storage fees are:

Period	Standard-Size	Oversize
January - September	$0.78/cubic foot	$0.56/cubic foot
October - December (peak)	$2.40/cubic foot	$1.40/cubic foot

That peak-season jump is 3x the off-peak rate for standard-size items. If you’re stocking up for Q4, you’re paying Q4 storage rates on every unit that arrives early.

Run the numbers on a specific product. Say you sell a standard-size item that measures 14” x 10” x 4” packed (about 0.32 cubic feet). Off-peak, that’s roughly $0.25/unit/month in storage. During Q4, the same unit costs about $0.77/month. If you’re holding 1,000 units through November and December, the storage bill alone runs $1,540 - before you’ve paid a dime in fulfillment fees.

Your storage cost isn’t a fixed line item. It’s a variable that shifts with the calendar, and the math changes sharply depending on how fast you turn inventory. These fees apply per ASIN, so a broad catalog with uneven sell-through rates can rack up storage costs that don’t show up in your top-line numbers.

Amazon also enforces a Storage Utilization Surcharge if your inventory exceeds 26 weeks of supply, and a Low Inventory Level fee (as of 2026, calculated per seller-FNSKU) if you drop below 28 days of supply. You’re penalized for holding too much and for holding too little. Roughly 4-8 weeks of supply hits the sweet spot for most products, though seasonal catalogs need a different cadence - stagger your Q4 inbound shipments rather than shipping everything in September.

Aged Inventory Surcharges: The Cost of Sitting Still

Long-term storage fees have been replaced by the Aged Inventory Surcharge, and the timeline has gotten much shorter than most sellers expect. Units that have been in a fulfillment center for more than 180 days incur monthly surcharges that escalate with age. The rates start modest but jump sharply after 271 days:

Age of Inventory	Surcharge
181-210 days	$0.50/cubic foot
211-240 days	$1.00/cubic foot
241-270 days	$1.50/cubic foot
271-365 days	$5.45+/cubic foot (escalating by 30-day bands)
12-15 months	$0.30/unit or $6.90/cubic foot (whichever is greater)
15+ months	$0.35/unit or $7.90/cubic foot (whichever is greater)

That 181-day threshold catches a lot of sellers off guard. Six months feels like plenty of runway - until you realize you’re already paying surcharges on slow movers while you’re still deciding what to do with them. And the cliff at 271 days is steep: rates jump from $1.50 to $5.45 per cubic foot overnight.

The 12-15 month tier doubled from its prior rate of $0.15/unit. And the 15+ month tier is entirely new - previously there was a single rate for all inventory over 365 days.

If you have slow-moving inventory sitting in a fulfillment center, the math on removal orders becomes straightforward. At $0.35/unit/month for aged stock, a product with $2 in margin bleeds out in six months - check the Recommended Removal Report before surcharges eat your profit. Amazon does send alerts before surcharges apply, but by the time you get the notice, you’ve already burned through the cheapest window to act.

2026 Fulfillment Center Changes That Affect Your Operations

Early 2026 brought three changes worth your attention:

FBA Prep and Labeling Services Are Gone

As of January 1, 2026, Amazon stopped providing prep and labeling services entirely. No more FNSKU labeling, poly-bagging, bubble wrapping, or repackaging at the fulfillment center. Every inbound shipment must arrive 100% prepped and compliant.

This is not optional. Inventory that arrives unprepped may be rejected, returned, or disposed of without reimbursement. And the penalty for inbound defects has jumped sharply - standard-size inbound defect fees now range from $0.32 to $1.74 per unit (up from $0.02-$0.07), and bulky items can be hit with up to $5.72 per unit. That’s a 10-80x increase in defect penalties.

If you were relying on Amazon’s prep services, you need a third-party prep provider or in-house capability now.

March 31, 2026: The End of Commingled Inventory

Brand owners in Brand Registry should be paying attention here. Amazon is ending commingled (stickerless) inventory practices, and for once, the change benefits you: you can switch to manufacturer barcodes and skip FNSKU stickering entirely. Amazon estimated brand owners were spending $600 million per year on re-stickering alone.

For resellers, the picture is different. FNSKU barcodes are now mandatory. Inventory without proper barcodes will be treated as defective. Previously, Amazon could fulfill an order using the closest matching unit from any seller’s inventory - that’s over. Each seller’s inventory is tracked separately. If you sell stickerless, commingled inventory, this change requires immediate action.

New Size Tiers Reshape Fulfillment Fees

A new “Small Bulky” size tier (products with 18-37” longest side or 20-50 lbs) now sits between Large Standard and Large Bulky. Fees for this tier are 21-23% lower than the old Large Bulky classification. If you sell mid-size products that were previously classified as Large Bulky, check whether they now qualify - the savings are significant. A 10 lb product, for example, dropped from $9.61 to $7.55 in fulfillment fees.

How Fulfillment Center Assignment Affects Your Costs

Amazon assigns your inventory to fulfillment centers based on its own demand forecasting. You don’t get to choose, but you can influence the outcome - and the cost differences are real.

Factor	What It Means for Your Costs
Inbound placement	Send to fewer locations for a fee, or distribute yourself at lower cost. Storage rates also vary by region.
Inventory distribution	More FCs = faster delivery and stronger Buy Box metrics, but more complexity for removal orders and Settlement Report reconciliation.
Returns routing	Returned items don’t always go back to the originating FC, which can create inventory imbalances that affect storage utilization.

Amazon optimizes for buyer experience, not seller convenience. Your job is to manage your inventory velocity and unit economics so that wherever Amazon puts your product, the math still works.

Here’s a framework for thinking about your inventory timing against these fees:

Weeks of Supply	Risk	Action
Under 4 weeks	Low Inventory Level fee kicks in	Replenish immediately or accept the per-unit penalty
4-8 weeks	Optimal zone	Monitor sell-through weekly
8-26 weeks	Safe but watch Q4 rates	Clear slow movers before October
26-38 weeks (181-270 days)	Aged Inventory Surcharge begins ($0.50-$1.50/cu ft)	Run removal math - it’s minor now but compounds
39+ weeks (271 days)	Aged surcharge jumps to $5.45+/cu ft	Liquidate or remove - the margin math is probably already negative

Running the numbers on your fulfillment costs? Feedvisor’s platform optimizes pricing and advertising across your entire Amazon catalog, factoring in real-time fee structures and inventory costs. See how it works.

FAQ

How many fulfillment centers does Amazon operate?

Amazon operates over 110 fulfillment centers in the United States and hundreds more globally, including sortation centers, delivery stations, and air hubs. The footprint has more than doubled since 2020.

Can I choose which Amazon fulfillment center stores my inventory?

No. Amazon assigns fulfillment center locations based on product size, category, and demand forecasting. You can influence distribution through inbound placement options, but final assignment is Amazon’s decision.

When do aged inventory surcharges start?

Surcharges begin at 181 days - not the 271 or 365 days many sellers assume. The initial rates are relatively modest ($0.50-$1.50 per cubic foot for 181-270 days), but they jump to $5.45+ per cubic foot at 271 days. Monitor your Inventory Health Report and submit removal orders well before the 271-day cliff.

How do 2026 FBA storage fees compare to previous years?

Monthly storage fees held steady from 2025 to 2026 at $0.78/cubic foot (Jan-Sep) and $2.40/cubic foot (Oct-Dec) for standard-size items. The bigger change is in aged inventory surcharges, where the 12-15 month tier doubled to $0.30/unit and a new 15+ month tier of $0.35/unit was introduced.

Do I still need to prep my own inventory for fulfillment centers?

Yes, since January 1, 2026. Amazon ended all FBA prep and labeling services. Inventory must arrive fully prepped - labeled, poly-bagged, and compliant with Amazon’s requirements. Non-compliant shipments face inbound defect fees of $0.32-$5.72 per unit, or may be rejected outright.