Seller Transparency Hub

Original research

Marketplace Fee Impact Reports

Independent analyses quantifying how each fee change actually affects seller margin — with methodology, sample size, and affected categories disclosed up front.

3
Reports published
400
Fee combinations analyzed
2026-05-20
Latest report
Amazon
2026-05-20

Amazon FBA Fee Restructure 2026: Quantifying the 12–16 oz Reclassification

The May 2026 FBA restructure quietly moved items in the 12–16 oz band into a higher fulfillment tier. For sellers concentrated in Home & Kitchen and Toys, the per-unit fulfillment cost rose by $0.42 on average — a ~7.7% increase on the previous tier rate.

Estimated impact+$0.42 per unit on affected SKUs
Sample size150 fee combinations
Affected categories
Home & KitchenToys & GamesTools & Home Improvement
Amazon
2026-05-04

Low-Inventory-Level Fee: Who Actually Pays It Now

Raising the trigger to 28 days of supply roughly doubles the number of SKUs exposed to the fee. For lean-inventory sellers practicing JIT, the effective hit is ~0.8% of revenue on affected items — a meaningful drag on already-thin margins.

Estimated impact+0.8% of revenue for affected SKUs
Sample size200 fee combinations
Affected categories
All standard-size SKUs
Walmart
2026-04-12

Walmart Sporting Goods Referral Cut: A Real Win for Mid-Market Sellers

Walmart cut the sporting goods referral fee from 15% to 13% for items under $100 — a rare downward adjustment. On a $49.99 SKU, this is roughly $1 of margin returned to the seller per unit, with no operational changes required.

Estimated impact-200 basis points referral on items under $100
Sample size50 fee combinations
Affected categories
Sporting Goods

Methodology, briefly

Every report draws on the same underlying fee database and change feed. We document the sample, the assumptions, and the source URLs — so every number can be traced back to a public marketplace policy page.

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