The same item, two platforms, two different answers

Each platform's published 2026 fee schedule is applied to the same item — same price, same unit cost, same shipping — and the results are ranked by net cash per sale. Nothing is averaged and no platform is given a benefit of the doubt on fees it does not charge.

Because the fee structures differ in shape, not just in size. Percentage fees scale with price, fixed fees do not. Poshmark's $2.95 flat fee and StockX's $4 inbound shipping hurt cheap items and disappear on expensive ones; percentage-only platforms like Mercari behave the opposite way. There is usually a crossover price, and these pages name it.

No, and no fee table can. They compare what you keep per sale assuming the sale happens. A platform with a 20% fee and ten times the buyers can be worth far more than one with a 4% fee and none — that trade-off is discussed in the text of each comparison rather than folded into the number.

For US sellers in 2026, Depop has the lowest mandatory platform cost at 3.3% + $0.45 with no commission, followed by Shopify at 2.9% + 30¢ plus a monthly subscription. Both come with the same catch: neither brings you buyers. Among marketplaces that supply demand, Mercari at 10% flat and Walmart at 15% are the cheapest.