How to Reduce Amazon FBA Fees: Step-by-Step Optimization Guide

Why FBA fees eat into your margin

Fulfillment by Amazon gives sellers Amazon's shipping network, Prime eligibility and customer service. But if you don't watch your settings, FBA fees quietly erode your margin. Storage surcharges and unnecessary dimensional-weight charges are the usual culprits. Here are ten ways to cut them.

1. Optimize packaging to drop a size tier

Amazon sets fulfillment fees mainly by product dimensions and weight, grouped into size tiers such as small standard, large standard and oversize. Crossing a tier threshold by a fraction of an inch can raise your per-unit fee significantly.

• Remove empty space inside the box or polybag.
• Use custom-fit boxes instead of off-the-shelf packaging.
• Switch from rigid boxes to lightweight polybags or bubble mailers where the product allows it.

2. Avoid oversize classification

Oversize items cost far more to store and ship than standard-size ones, and a product sometimes lands in oversize only because of bulky retail packaging or extra padding.

• Check your boxed dimensions against Amazon's standard-size limit, 18 × 14 × 8 inches.
• Fold, compress or ship items such as clothing, gear and modular accessories disassembled so they fit.

3. Audit your dimensions and request remeasurement

Amazon measures and weighs products automatically in its fulfillment centers, and mistakes are common. A small error, repeated across thousands of units, adds up quickly.

• Compare your own measurements with the dimensions shown in your FBA fee preview in Seller Central.
• If they are wrong, open a case in Seller Central and ask for a physical remeasurement.
• If Amazon confirms the error, request a fee adjustment for orders that were overcharged.

4. Control aged inventory surcharges

Amazon charges an aged inventory surcharge on stock held in fulfillment centers for more than 180 days, and the rate rises further after 365 days. Slow-moving stock also ties up cash.

• Keep 30 to 60 days of stock on hand and reorder from real sales data rather than sending large shipments at once.
• Clear slow movers with discounts, promo codes or outlet deals before surcharges build up.
• Create removal or liquidation orders for items that aren't selling.

5. Use a hybrid FBA and FBM strategy

FBA isn't the cheapest option for every SKU. Heavy, bulky or slow-selling products often cost more to fulfill and store than they earn.

• Find SKUs whose fees are high relative to their selling price.
• Fulfill those yourself (FBM) or through a third-party logistics provider.
• If you qualify, use Seller Fulfilled Prime to keep the Prime badge while handling storage and shipping yourself.

6. Bundle products into multipacks

Amazon charges a fulfillment fee per unit shipped, so on low-priced items the fee can take a large share of the sale. Packaging two, three or four units as one product (for example, a 3-pack under one ASIN) means one fee for the bundle, which lowers the fee per item and improves your margin while giving customers better value.

7. Cut inbound shipping costs

Getting inventory into Amazon's network is a real part of your logistics cost.

• Use the Amazon Partnered Carrier program for discounted less-than-truckload and full-truckload rates.
• Pack pallets as fully as possible without exceeding weight and height limits.
• Consolidate small, frequent shipments into larger ones to lower cost per unit.

8. Prevent low-inventory-level fees

Amazon charges a low-inventory-level fee on standard-size items when your stock falls too low compared with your recent sales rate.

• Check your days of supply regularly in Seller Central.
• Keep at least the buffer stock Amazon recommends.
• Set reorder alerts that allow for your supplier's production and shipping time.

9. Reduce returns

Returns bring processing fees and often leave stock that can't be resold as new.

• Make images, size charts and descriptions show the product accurately.
• Tighten quality control and remove faulty units before they ship to Amazon.
• Include clear instructions to prevent "item not working" returns.

10. Claim reimbursements for lost and damaged inventory

With millions of packages moving every day, some of your units will be lost, damaged or miscounted. If Amazon doesn't reimburse you automatically, you pay for stock you can't sell.

• Reconcile inbound shipments to confirm every unit sent was received.
• Review inventory reports for units marked lost or damaged.
• File reimbursement claims in Seller Central on time, with supplier invoices as proof.

Summary

Reducing FBA fees is an ongoing job, not a one-time fix. Tight packaging, accurate measurements, healthy stock levels and regular reimbursement checks together protect your margin. Booking each fee type separately in your accounts shows you which of these is costing you most.