Seller guide
How do I find FBA promotion discounts that erased my margin?
Rebuild contribution from seller-supplied FBA shipped-item promotion rows, separate expected discounts from unexpected stacking, and rank negative or below-floor outcomes without claiming causation.
Start with shipped-item economics at one consistent grain
Use one row per seller-normalized shipped item and preserve a non-customer reference, shipment date, SKU, quantity, unit price, promotion ID, promotion discount, other discount, marketplace fee, fulfillment fee, product cost, and other supplied variable cost. Keep currency and marketplace fixed across the batch. Do not upload buyer identity or address fields, and do not mix order-level discount totals with item-level revenue unless the allocation is documented.
Reconcile the discount before interpreting margin
Calculate gross item revenue as unit price times quantity. Add promotion and other discounts, then verify that the total does not exceed gross revenue for the row. Subtract the discounts to obtain post-discount revenue. A mismatch can come from aggregation, refunds, tax treatment, or transcription, so preserve it as a source-data exception rather than forcing a zero or moving the difference into another fee bucket.
Calculate contribution with every supplied variable cost
Subtract marketplace fees, fulfillment fees, product cost times quantity, and other variable cost from post-discount revenue. Show total and per-unit contribution, then compare per-unit contribution with the seller's declared floor. This is a bounded contribution model, not net income: advertising, returns, storage, tax, overhead, and other omitted amounts remain outside unless the seller supplies them consistently.
Keep loss, floor pressure, and stacking as separate signals
A negative-contribution row, a positive row below the seller's floor, and a row whose discount count exceeds the seller's expected stack threshold answer different questions. Rank them separately and aggregate totals by supplied promotion ID so recurring exposure is visible. An unexpected-stack flag is relative to the seller's threshold; it does not prove the marketplace applied an invalid discount or that promotions caused the sale.
Verify the live promotion and settlement before changing anything
Compare queued rows with the authorized promotion setup, discount funding, shipment economics, returns, settlement, and current program terms. Check whether overlapping coupons, price discounts, Business pricing, Subscribe & Save, or other programs are represented consistently in the source. Friday does not end a promotion, change a price, publish a listing, submit a claim, or modify a seller account; a human decides any action after source verification.
Tools that help with this
Prices below are exact x402 per-call prices. Human card checkout uses fixed $3, $9, and $29 bundles; follow a tool page to see its applicable bundle.
- FBA Promotion Discount Leakage Auditor ($0.50) — Rank supplied shipped-item rows by negative margin, floor pressure, and stacking
- Coupon and Deal Incremental ROI Calculator ($0.25) — Compare a promotion period with a seller-chosen baseline as a separate analysis
- Marketplace Payout Reconciliation Analyzer ($1.00) — Trace verified promotion components through a supplied settlement and deposit
Every paid output is a draft for your review before you publish, appeal, or activate anything. Friday does not access your seller account.