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Compare Amazon SKU contribution using sales, settlement, fee, advertising, and product-cost exports. Work through the spreadsheet formulas, reconcile contribution to the settlement, and separate product economics from company operating profit.
Amazon profitability analysis starts with net sales by SKU and subtracts the costs attributable to those sales. Reconcile that contribution to settlement activity, then deduct shared operating expenses before calling the result operating profit.
The useful question for a US seller is which products earn their place after fees, fulfillment, returns, and acquisition costs. Revenue and bank deposits answer different questions. The broader profitability analysis framework explains the levels of profit; this method connects those levels to seller exports.
Choose a closed reporting period, one marketplace, and USD. Use the same SKU mapping across sales and cost files, preserving the original order and transaction identifiers for reconciliation. Keep a separate list of unmapped transactions until someone resolves them.
| Export | Rows to retain | Purpose |
|---|---|---|
| Sales and refunds | Order item, SKU, transaction date, sales, refund amount | Establish net sales |
| Settlement and fees | Transaction ID, order reference, charge type, amount, settlement period | Classify charges and reconcile cash activity |
| Product costs | SKU, effective date, landed cost, units sold, return adjustments | Compute cost of goods sold |
| Advertising | Reporting period, advertised SKU, assigned spend | Attach direct advertising costs |
| Storage and operating ledger | Period, cost category, SKU where available | Include storage and shared expenses |
Amazon distinguishes selling-plan fees from referral fees, with referral charges depending on category; use the charges actually recorded in your export rather than applying a universal rate (Amazon selling fees). Its fulfillment program also has separate fulfillment and storage costs, so neither should disappear into a single unexplained deduction (Amazon fulfillment cost categories).
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Do not add sales transactions from an order file to the corresponding sales transactions in a settlement file. Choose one financial record for each event; use the other file to supply attributes or verify the amount. An order can have several later charges and credits, so matching by order alone does not establish a unique transaction.
Use positive amounts for the deductions below. Net referral charges include applicable credits; landed COGS reflects the company's reviewed treatment of returned inventory. Exclude amounts collected on behalf of taxing authorities from this sales basis.
SKU contribution = Gross sales − Customer refunds − Net referral charges − Fulfillment − Landed COGS − Assigned advertising − Storage
Contribution margin = SKU contribution / Net sales
A fictional Ohio home-goods seller has the following September 2026 records. These are illustrative recorded costs, not an Amazon fee schedule. Put the table in columns A through H, with headers in row 1.
| SKU | Gross sales (USD) | Refunds (USD) | Referral (USD) | Fulfillment (USD) | Landed COGS (USD) | Advertising (USD) | Storage (USD) |
|---|---|---|---|---|---|---|---|
| AX-10 | 10,000 | 500 | 1,500 | 1,200 | 4,000 | 600 | 200 |
| BZ-20 | 8,000 | 800 | 1,200 | 1,600 | 3,600 | 700 | 300 |
| CY-30 | 6,000 | 300 | 900 | 900 | 2,400 | 400 | 100 |
| Total | 24,000 | 1,600 | 3,600 | 3,700 | 10,000 | 1,700 | 600 |
Add net sales in I, contribution in J, and margin in K. Enter these Google Sheets formulas in I2, J2, and K2 respectively, then fill down through row 4. The SUM expressions add selected cells or ranges using Google's documented SUM syntax.
=B2-C2
=I2-SUM(D2:H2)
=IF(I2=0,"",J2/I2)
Format K as a percentage. Retain full precision in the worksheet and display margins to one decimal place.
| SKU | Net sales (USD) | Contribution calculation (USD) | Contribution (USD) | Margin |
|---|---|---|---|---|
| AX-10 | 9,500 | 9,500 − 1,500 − 1,200 − 4,000 − 600 − 200 | 2,000 | 21.1% |
| BZ-20 | 7,200 | 7,200 − 1,200 − 1,600 − 3,600 − 700 − 300 | -200 | -2.8% |
| CY-30 | 5,700 | 5,700 − 900 − 900 − 2,400 − 400 − 100 | 1,000 | 17.5% |
| Total | 22,400 | 22,400 − 3,600 − 3,700 − 10,000 − 1,700 − 600 | 2,800 | 12.5% |
The total margin is =SUM(J2:J4)/SUM(I2:I4), not the average of the SKU margins. BZ-20 has positive sales but negative contribution on this stated cost basis. Its owner should investigate the underlying costs before increasing its sales target.
For this example, all sales, refunds, referral charges, fulfillment, and storage settle in September. Advertising is billed separately; there are no reserves, payout delays, or other settlement adjustments. Those assumptions let the following bridge reconcile exactly.
| Bridge from the records above | Amount (USD) |
|---|---|
| Net sales | 22,400 |
| Less referral charges | -3,600 |
| Less fulfillment | -3,700 |
| Less storage | -600 |
| Settlement amount | 14,500 |
| Less landed COGS | -10,000 |
| Less advertising billed separately | -1,700 |
| Contribution | 2,800 |
In the worksheet, settlement amount is =SUM(I2:I4)-SUM(D2:E4)-SUM(H2:H4). Subtract SUM(F2:G4) to recover the same contribution as SUM(J2:J4); their difference must be zero.
In a real close, keep reserve movements, pending transfers, and timing differences on separate bridge lines. Tie settlement totals to their reports and bank receipts before interpreting unexplained differences as profit. The related merchant profitability analysis covers the broader merchant view.
The seller also has these September expenses, recorded outside the SKU table:
| Shared expense | Amount (USD) |
|---|---|
| Administrative payroll | 1,200 |
| General office and software expense | 600 |
| Total shared overhead | 1,800 |
Operating profit is therefore $2,800 − $1,800 = $1,000 on the stated basis. Do not label the $2,800 contribution as company profit. If the team needs allocations for account or channel decisions, use explicit drivers as described in cost to serve per customer.
A sensitivity changes one input: lower BZ-20 storage from $300 to $100 while holding every other amount fixed. Its contribution becomes $0 because the $200 reduction offsets its $200 loss. That identifies a break-even requirement; it does not establish that such a storage reduction is operationally available.
Bring your sales, settlement, fee, and product-cost files, with any advertising and storage records needed for the same period. Covirage maps the columns, its tools compute and check the figures, and the external AI model explains the results with every figure traced to its rows. Create a free Covirage account and bring a sample of your own data.
See customer profitability for the supporting approach to contribution and cost comparisons.
No. A payout reflects the transactions and adjustments included in a settlement. Product costs, advertising billed separately, and shared operating expenses may sit outside it. Reconcile the payout to its transactions, then build a separate period profit calculation.
Include net selling fees, fulfillment, landed cost of goods sold, directly assigned advertising, and storage or other costs allocated on an explicit basis. Keep shared overhead separate until contribution reconciles, and document any expense that cannot be assigned reliably.
Deduct customer refunds from sales and record related fee credits separately from their original charges. Adjust product costs only when the inventory accounting supports it. A refunded sale does not prove that the returned item can be resold.
Yes. Additional sales can come from products with weaker contribution, greater advertising costs, or more returns. Compare contribution dollars and contribution margin by SKU, then reconcile the change to the whole business before deciding whether growth improved operating profit.