What a $1 coupon actually costs you (it is not $1)

A coupon costs you the discount plus $0.60 every time a shopper clips it. If you offer a dollar off and ten people clip it, you paid $1.60 each, or $16 total. Not the end of the world on a single product. But across 50 SKUs each getting a modest number of redemptions, the clip fees stack into a real number that never shows up on your product page.

The mistake I see most often is treating the coupon as pure discount — "$1 off, so it costs me $1 per unit." It costs $1.60 per redeemed unit, and a lot of people clip a coupon without buying. Those clips cost you the $0.60 but produce no sale. On a product with a high browse-to-buy ratio, the non-buyers' fees can equal the buyers'.

Where it hurts

A low-margin product absorbs a coupon fee poorly. If your net is $4 a unit and one coupon redemption costs $1.60, that's 40% of the margin on a single coupon. If a third of people who see the product clip without buying, the effective cost of getting each coupon sale is even higher.

High-margin products don't feel it as much. But the fee adds a fixed floor to the coupon strategy — no matter how cheap your product is, the $0.60 clip fee does not shrink.

When it makes sense

Coupons work when you need a visible discount to outrank competitors or when the Amazon algorithm seems to give a small boost to products running one. The boost is debatable and inconsistent, but if it moves the needle on rank, the cost can be worth it.

Run the numbers before you set the coupon. A $1-off on a $30 product at 30% net is tolerable. A $3-off on a $12 product at 15% net is probably losing you money on every unit you sell through the coupon. Use a coupon calculator to check before you turn it on, and treat the clip fee as a line item, not an afterthought.