Amazon FBA fees, explained

Amazon's commission on each sale — a percentage of the total price (commonly around 8–15% depending on category), taken whether you use FBA or fulfil yourself. This is usually the single biggest deduction after the cost of the product itself.

A flat per-unit fee for picking, packing and shipping the order, based on the item's size and weight tier. Larger and heavier items cost more. This replaces your own shipping cost — the trade is convenience and Prime eligibility for a fixed per-unit charge.

A fee for the warehouse space your stock occupies, charged per cubic foot/metre and higher in peak season (Q4). Slow-moving stock quietly racks this up month after month, so it is a real reason not to over-order.

An extra surcharge on inventory that sits too long (typically beyond several months). It is designed to push you to clear dead stock. The longer a unit sits unsold, the more each eventual sale really cost you.

A returned unit can cost you the refunded sale, return processing, and sometimes unsellable stock you cannot resell. Spread across all your sales, a high return rate can erase a thin margin entirely — yet it rarely shows in a revenue dashboard.

Removal/disposal fees, FBA inbound placement fees, labelling and prep fees, and low-inventory or aged-inventory surcharges. None is huge alone, but together they decide whether a "profitable" SKU actually is.

True profit per unit = selling price − product cost − every fee above − the ad spend behind the sale. A quick "price minus cost" almost always overstates it. Work a single product on the profit calculator, or let AIAdKing pull your real fees and compute it per SKU automatically.