UserToolbox / Blog
Trade Tools · 8 min read ·

Amazon FBA Fees Calculator 2026: Every Fee Explained with Examples

Amazon's fulfilment fees have never been a single number. Between referral percentages, size-tier-based fulfilment charges, monthly storage rates, aged-inventory surcharges, and the occasional placement fee, sellers routinely underestimate their true cost of sale — and list products that look profitable on paper but deliver a loss at checkout. Getting this wrong at the sourcing stage is one of the most common reasons new FBA businesses stall.

This article breaks down every major FBA fee category in effect for 2026, explains how each one is calculated, and walks through a worked example with real numbers so you can see exactly how margin erodes from selling price to net payout. It also covers the free UserToolbox FBA Fee Calculator — a browser-based tool that does the arithmetic in seconds without requiring a Seller Central login.


How Amazon's fee structure is organised in 2026

Amazon charges sellers through several distinct fee categories, each with its own calculation logic. Understanding the hierarchy matters because some fees are flat per-unit charges, some are percentage-based, and some depend on physical dimensions or how long stock sits in a warehouse. Conflating them — or missing one entirely — produces an inaccurate margin model.

The primary fees every FBA seller encounters are the referral fee, the fulfilment fee, and the monthly inventory storage fee. Beyond those, sellers with slower-moving stock will encounter aged inventory surcharges. Sellers sending large shipments to a single fulfilment centre may also face inbound placement service fees, introduced more prominently in 2024 and still in effect for 2026.

Amazon updates its fee schedule — typically in February — so any calculator or spreadsheet built on prior-year figures will produce errors. The rates used throughout this article reflect the 2026 schedule published in Seller Central. If you are reading this later in the year, cross-reference against the current fee schedule before making sourcing decisions.

💡

Pull the official fee schedule PDF from Seller Central's "Fee Explainer" section at the start of each year. Save it with the date in the filename so you always know which year's rates your margin models are using.

FBA fulfilment fees: size tiers, dimensional weight, and the 2026 rate card

The fulfilment fee is usually the largest single line item for non-apparel products. Amazon assigns every ASIN to a size tier based on its dimensions and weight when packaged. The two most commonly encountered tiers are Small Standard (items up to 15 × 12 × 0.75 inches and under 16 oz) and Large Standard (items up to 18 × 14 × 8 inches and under 20 lb). Beyond that, items fall into Small, Medium, Large, or Special Oversize — each significantly more expensive per unit.

Within each tier, the fee is calculated on the greater of actual shipping weight or dimensional weight. Dimensional weight is calculated as (length × width × height) ÷ 139 for standard items. A lightweight but bulky product — say, a foam roller in a large box — can be charged at a much higher weight bracket than its actual weight suggests. Many sourcing errors trace back to a seller measuring weight on a kitchen scale and ignoring the dimensional calculation entirely.

For 2026, Amazon also maintained a fee discount programme for products in the "Low Price FBA" category — items selling at or below $10 — which carry a reduced per-unit rate to remain competitive with lower-cost fulfilment alternatives. Check eligibility before assuming standard rates apply to budget-priced lines.

Free Tool

FBA Fee Calculator

Enter your product's selling price, dimensions, weight, and category to get an instant breakdown of every FBA fee and your estimated net payout — no Seller Central login needed and far faster than working through Amazon's rate tables manually.

Try it free →
💡

Measure your product in its final packaged state, not bare. Amazon's fulfilment centre will measure and weigh items on receipt, and if the packaged dimensions push the ASIN into a higher size tier, your fee will be re-rated accordingly — often without an explicit notification.

Referral fees, storage fees, and the other charges you cannot ignore

The referral fee is straightforward in concept but easy to underestimate in practice. For most categories — home goods, sports, tools, kitchen — it sits at 15% of the selling price. Electronics is lower at 8%. Clothing and accessories is 17%. Fine jewellery and watches carry tiered rates that can reach 20%. The minimum referral fee of $0.30 per item applies when the percentage amount is lower than that threshold, which catches sellers of very low-price consumables by surprise.

Monthly storage is charged per cubic foot. From January through September the standard rate is approximately $0.78 per cubic foot for standard-size items. From October through December that rate rises to approximately $2.40 per cubic foot — a threefold increase. Oversize items are cheaper per cubic foot but occupy far more space. A seller holding 500 units of a 1-cubic-foot product through November is paying around $1,200 in storage alone that month.

The low-inventory-level fee, active since 2024, adds a further per-unit charge when your 28-day and 90-day historical days of supply fall below Amazon's thresholds. For sellers running lean on purpose to reduce storage costs, this fee can appear unexpectedly. Maintaining a minimum buffer of 28 days of supply is the standard mitigation approach.

💡

Check the category for your ASIN in the Product Classifier tool inside Seller Central before listing. Amazon occasionally re-categorises items after listing, which can change the referral fee percentage. Build a small buffer into your pricing model to absorb a one- or two-point category rate shift.

Worked example: calculating net payout for a Large Standard product

Consider a private-label kitchen accessory sold at $24.99. The product weighs 14 oz in its packaging, measures 10 × 7 × 3 inches, and sits in the Kitchen category. The seller is sourcing 200 units from a manufacturer at $4.50 per unit landed (including freight and import duty). Here is how the FBA fee stack reduces the $24.99 selling price to a net payout.

First, the referral fee: Kitchen carries a 15% rate, so 15% of $24.99 equals $3.75. Next, the fulfilment fee: at 14 oz the product is Large Standard, putting the fulfilment fee at approximately $4.25 per unit. Monthly storage adds a per-unit cost; assuming average inventory of 100 units at 0.15 cubic feet each (1.5 cubic feet) at the off-peak rate of $0.78 per cubic foot, that is $1.17 per month spread across estimated monthly sales of 50 units — roughly $0.02 per unit. For simplicity we will round storage contribution to $0.05 per unit when averaged across a full year including Q4 peak months.

Subtracting all FBA fees from the selling price: $24.99 − $3.75 (referral) − $4.25 (fulfilment) − $0.05 (storage allocation) = $16.94 gross payout per unit. Deducting the $4.50 cost of goods leaves $12.44 gross profit per unit before advertising spend, return allowance, and any FBA placement fees. That works out to approximately 49.8% gross margin on cost of goods, or 49.8% net of FBA fees — a solid position for a private-label product, but one that can contract quickly if advertising ACoS runs high or return rates climb.

💡

A rough rule of thumb used by experienced FBA sellers: Amazon fees (referral + fulfilment) typically consume 25–35% of selling price for standard products. If your combined fees exceed 40% of selling price, you should re-examine whether FBA is the right fulfilment route, or whether repricing is possible.

Aged inventory surcharges and inbound placement fees: the costs sellers miss most

Aged inventory surcharges are assessed monthly on units that have been in a fulfilment centre for more than 181 days. The current schedule charges approximately $0.50 per cubic foot per month for units aged 181–270 days, rising to $1.50 per cubic foot per month at 271–365 days, and $6.90 per cubic foot per month (or $0.15 per unit, whichever is greater) beyond 365 days. These numbers compound: a seller with 50 units of a 0.3-cubic-foot product sitting at the 365-day mark is paying over $100 per month simply to store unsold stock.

The inbound placement service fee is less intuitive. When Amazon receives a shipment, it distributes inventory across its fulfilment network. If a seller opts to send everything to a single location rather than splitting shipments to multiple warehouses (as Amazon prefers), Amazon charges a placement fee per unit to redistribute the stock itself. For standard-size items, this fee is typically $0.27–$0.38 per unit for the minimal-split option. Sellers who manage their own multi-warehouse splits using Amazon's "Distributed" option can avoid this entirely, at the cost of more complex inbound logistics.

The practical defence against both of these fees is inventory hygiene. Set up automated alerts in your inventory management system at the 120-day mark — well before the 181-day threshold — so you have time to run a promotion, lower price, or submit a removal order. For