What is FBA?
Fulfillment by Amazon — Amazon stores, picks, packs, and ships your inventory.
FBA stands for Fulfillment by Amazon, the program in which Amazon stores, picks, packs, ships, and handles customer service and returns for your inventory. With Amazon FBA, you send units into Amazon's fulfillment network, and Amazon takes over the logistics — including the Prime badge that drives conversion. It's the dominant model for serious Amazon sellers precisely because it outsources the warehouse and the last mile to the company that owns the buying experience.
The trade-off is fees and complexity. Fulfillment by Amazon charges a per-unit fulfillment fee plus monthly storage, and layers on extras like aged-inventory surcharges, removal fees, and returns processing. Those fees come straight out of each settlement, so FBA can quietly compress margins if you aren't tracking the full cost stack per SKU. Understanding what FBA costs — and what Amazon owes you back when it mishandles your stock — is central to running it profitably.
How Amazon FBA works, step by step
The FBA workflow is consistent across products. You create a shipment in Seller Central, label each unit with its FNSKU barcode (or use Amazon's labeling service), and send the inventory to the fulfillment centers Amazon assigns — often split across multiple locations. Once received, your units become Prime-eligible and Amazon handles everything downstream when an order comes in.
From there Amazon owns the operational chain end to end, which is the appeal and the reason fees stack up. Each step is a service you're paying for, and each is a place where things can go wrong in ways that create money Amazon owes you back.
- •You ship labeled units into Amazon's fulfillment network
- •Amazon stores them and lists them as Prime-eligible
- •On each order, Amazon picks, packs, and ships to the customer
- •Amazon handles customer service and processes returns
- •Amazon deducts fulfillment and storage fees from your settlements
Amazon FBA fees: the cost stack to model
An Amazon FBA calculator helps, but you should understand the structure rather than memorize numbers, because rates change by category, size tier, and season and should always be verified against Amazon's current fee schedule. The fulfillment fee scales with the unit's size and weight; monthly storage is charged per cubic foot and rises sharply in Q4; and additional charges apply for inventory that ages past storage thresholds, for removals, and for returns processing.
These fees don't sit in a tidy place — they're scattered through your settlement reports alongside referral fees and ad spend. Booking them accurately, per SKU, is what reveals true net margin. A product that looks healthy on referral fee alone can be a loser once the FBA fulfillment fee, storage, and an aged-inventory surcharge are stacked on top. Pulling the real per-unit fee load from settlement data is exactly the kind of thing BeanHawk handles so your margins reflect reality.
FBA reimbursements: money Amazon owes you back
Because Amazon physically handles your inventory at massive scale, it routinely loses, damages, or mis-charges units — and owes you a reimbursement when it does. Lost inbound units, warehouse-damaged stock, customer returns that were refunded but never returned to your inventory, and overcharged dimensional weight all generate reimbursement claims. This is real, recoverable money that most sellers never fully collect because the discrepancies are buried in reports.
Reconciling FBA inventory and fees against what Amazon actually did is a recurring source of "found money," and it's directly an accounting problem: it requires matching shipments, settlements, and inventory ledgers. Catching these discrepancies systematically — rather than spot-checking — is how sellers recover what they're owed before claim windows close.
Frequently asked questions
- What is Amazon FBA?
- FBA stands for Fulfillment by Amazon. You send your inventory to Amazon's fulfillment centers, and Amazon stores it, then picks, packs, and ships each order, handles customer service, and processes returns. Your products also become Prime-eligible. In exchange, Amazon charges per-unit fulfillment and monthly storage fees.
- What does Amazon FBA cost?
- FBA charges a per-unit fulfillment fee based on size and weight, plus monthly storage fees per cubic foot, with additional charges for aged inventory, removals, and returns. Rates vary by category, size tier, and season, so verify them against Amazon's current fee schedule and model the full stack per SKU rather than relying on a single number.
- How do I calculate FBA fees before sourcing a product?
- Use the Amazon FBA revenue calculator to estimate the fulfillment and storage fees for a product's size and weight, then add the referral fee and your landed cost to find true margin. Treat it as an estimate and confirm current rates, since fees change by category and season.
- What is an FBA reimbursement?
- It's money Amazon owes you when it loses, damages, or mishandles your FBA inventory, or overcharges a fee — for example, units lost on the way into a warehouse or refunded returns that never came back to your stock. These claims are recoverable but easy to miss because the discrepancies are buried in inventory and settlement reports.
- Is FBA better than FBM?
- It depends on your products and operation. FBA wins on Prime access, conversion, and hands-off logistics but charges higher fees and storage. FBM (you ship it yourself) keeps fulfillment control and can be cheaper for bulky, slow, or high-margin items. Many sellers run both, choosing per SKU based on the margin math.
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