Do Seller Fees Apply to Shipping?

On eBay and Mercari, yes: the selling fee is charged on the item price plus the shipping the buyer pays. On Poshmark, no: the commission is charged on the item price only, and buyer-paid shipping is left out. The percentage rate gets all the attention, but the base it is charged on quietly decides what you keep. This page is about that base, one platform at a time. To turn it into an exact number, use each platform's calculator: the Mercari fee calculator here, or the eBay and Poshmark calculators linked below.

The fee base, platform by platform

Platform	Item price	Buyer-paid shipping	Figures verified
eBay	In the fee base	In the fee base	2026-07-24
Mercari	In the fee base	In the fee base	2026-07-30
Poshmark	In the fee base	Excluded	2026-07-30

Each date links to that platform's own fee page, the primary source, and is the date the figure was last verified there. Marketplace fee structures change, so if a date looks old, check the source before you rely on it.

Why the base matters more than sellers expect

Two platforms can advertise the same headline rate and still leave you with different amounts, because the rate is applied to different money. When buyer-paid shipping sits inside the base, as it does on eBay and Mercari, every dollar the buyer pays for shipping is also a dollar the fee is charged on. That is why the old trick of listing an item cheap and charging a lot for shipping does nothing for your fee on those two platforms: you moved the dollar, but it stayed in the base.

Poshmark is the exception that proves the point. Its commission is charged on the final order price and buyer-paid shipping is not part of that base, so shipping never enters the fee math at all. It is not a loophole you can work, because Poshmark sets the buyer's shipping as a fixed program price rather than letting you inflate it. It simply means that on Poshmark the fee you see is a fee on the item, full stop.

What is a cost to you versus what is in the base

Keep two different shipping numbers separate in your head. The shipping the buyer pays is what can land in the fee base. The label cost you actually pay the carrier is a cost that comes out of your own pocket and is never part of any platform's fee base. The calculators ask for these separately on purpose, because they move the result in opposite directions: what the buyer is charged can raise the fee, and what you pay for postage is a straight cost against your profit. For the full breakdown of every fee line on each platform, see 2026 platform fees and the 1099-K, and to weigh where to sell in the first place, choosing where to sell.

See it on your own numbers

The base is easiest to understand by watching it move. Put the same item price and the same buyer shipping into a calculator and change which number the shipping sits in:

Fee-and-shipping questions, answered

Do eBay fees include the shipping I charge the buyer?: Yes. eBay's final value fee applies to the total amount the buyer pays, which is the item price plus the shipping you charge them plus any sales tax eBay collects. Shifting money from the item price into the shipping charge does not lower your fee, because both sit in the same base.
Does Mercari charge its fee on shipping?: Yes. Mercari's selling fee is charged on the item price plus the buyer-paid shipping, the same base structure as eBay. The label cost you actually pay for postage is a separate cost to you; the fee is on what the buyer was charged.
Why is Poshmark different?: Poshmark charges its commission on the final order price only and leaves buyer-paid shipping out of the base entirely. On Poshmark the buyer typically pays a flat shipping fee that goes toward the label, so the platform does not treat that shipping as part of your sale for fee purposes. It is the one platform of the three where padding shipping does not raise your fee, because shipping was never in the base.
So should I lower my item price and raise shipping to save on fees?: On eBay and Mercari it changes nothing, because item price and buyer shipping are both in the fee base, so the fee is the same either way. On Poshmark buyer shipping is out of the base, but Poshmark's buyer shipping is a fixed program price you do not freely set, so there is no lever to pull. In every case, price for what the item is worth and let the calculator show you what you keep.