Seller guide
Run the break-even math before you drop a marketplace price.
A discount that lifts orders can still shrink profit once referral fees, fulfilment, and promotion costs move with it. The break-even volume check to run before activating any price cut or coupon.
Percentage thinking hides the real cut
A 10% price drop is not a 10% profit drop. Referral fees scale down with price, but fulfilment, packaging, and product cost do not — so the cut comes almost entirely out of your contribution margin. On a thin margin, a small discount can more than halve per-unit profit.
Break-even volume is the number that decides
Divide your current total contribution by the discounted per-unit contribution and you get the units you must now sell just to stand still. If the discount needs 60% more orders to break even, ask whether the marketplace has ever given you 60% more orders for 10% off that product. If not, the discount is a donation.
Coupons and deals add their own fees
Marketplace promotions often charge a per-redemption fee or a flat participation fee on top of the discount. Model the promotion's own cost per unit — a coupon that costs $0.60 per redemption on a $3 contribution changes the break-even far more than the sticker discount suggests.
Decide the exit before you enter
Set the volume threshold and the end date before activating. If the lift never covers the break-even volume, ending the promotion on schedule is the plan working, not the plan failing. Repricing back up is harder after months of anchoring, so short tests beat long drifts.
Tools that help with this
- Marketplace Price Change Break-Even Analyzer ($0.25) — Fee-aware break-even units and margin for any candidate price
- Marketplace Promotion Profit Guard ($0.25) — Check a coupon or deal's redemption fees against contribution
Every paid output is a draft for your review before you publish, appeal, or activate anything. Friday does not access your seller account.