Profit
Your bestseller might be your least profitable listing
A seller showed me his top listing. Great volume, sold every day, the pride of the store.
We worked out the real margin. On promoted sales, he was making pennies. Some days, less than pennies.
The reason is a timing trick in eBay's own numbers. When an order comes in, the earning you see reflects the sale. The Promoted Listings ad fee — the cut you paid to win that sale — often posts hours later, as a separate transaction. If you read the earning at the moment of sale, the ad fee isn't in it yet.
So the listing you promote hardest looks like your best performer, because the very fee that makes it your worst performer hasn't landed yet when you glance at it.
The number that lies to you
The order total is honest. The "earning" you eyeball on a fresh order is not, because it's incomplete. The only figure worth trusting is one that has settled — sale minus fees minus the ad fee that arrived on its own schedule.
Fetch Order Tracking reads earnings from eBay's Finances API, which includes the ad fees, and it waits for the sale to actually settle before trusting the figure. That's the difference between "this order made £3.02" and "this order made £3.02 but a £0.58 ad fee is coming, so it really made £2.44."
Multiply that gap across every promoted sale and your league table of listings can completely reorder. The hero becomes the drain. The quiet steady one becomes the earner.
Take your top promoted listing and subtract the ad fee from every sale for a week. Is it still your best?
For at least one listing, I'd bet the answer flips.