Industries · Retail

A healthy category margin can hide the line that loses.

Headline margin is taken at the shelf, before the deductions that actually decide whether a product made money: trade and promotional spend, returns and shrink, end-of-season markdowns, marketplace and channel fees. We rebuild margin from list price down to what truly stays, by product, channel and basket, so assortment and channel decisions rest on net margin rather than a category average.

Cost and Profitability Consulting · 150+ models since 2010 · TDABC

List → Net
every deduction made visible, by product and channel
Per channel
the same product can earn in one channel and lose in another
3 weeks
a fixed-fee ProfitAudit 360 maps net margin across the range
01Why headline margin misleads
Cumulative profit with customers ranked best to worst. The peak rises far above the final net; the tail gives the difference back. Illustrative data. net profit (what the board sees) profit on the table peak: more than the net you keep the accounts that earn it the small, urgent tail customers ranked by margin, best to worst illustrative
A few accounts create the profit. The small, urgent tail gives it back.

A category margin averages away the truth.

Most retail reporting stops at gross margin: shelf price minus cost of goods. Everything that comes after sits in separate ledgers and central cost lines: the promotion that moved the volume, the returns the product attracts, the shrink, the markdowns to clear it, the commission or listing fee the channel takes. Each is real money off the same product, and none of it touches the margin the buyer is judged on.

So a category looks healthy while a few lines and channels inside it lose money on every sale, funded by the rest. The range gets managed on shelf margin and volume, which is precisely the metric that cannot see the deductions deciding the outcome.

LIST PRICE TO NET MARGIN

Illustrative. From shelf price down through cost of goods and the deductions a category margin never shows, leaving a thin net margin that decides whether the line actually pays.

02A worked example

Same product, two channels, opposite outcome.

01

Same on the buying sheet

One product, one cost of goods, the same recommended price and the same 42% shelf margin whether it sells in store or on the marketplace.

02

Different after the shelf

In store, returns are low and there are no platform fees. Online, returns run at 14%, the marketplace takes commission, and promotional funding is needed to stay visible.

03

Net margin separates them

Deduct the real costs and the in-store channel nets +24% while the marketplace channel slips to −6%, on the identical product.

04

The fix is channel, not delist

Reprice for the channel, renegotiate the commission, or change the returns and promo model. The product can stay; the channel loss does not have to.

03The worked example, in numbers

Identical at the shelf, one channel funds the other.

Own storeMarketplace
Recommended price€40.00€40.00
Shelf margin42%42%
Returns3%14%
Channel & promo fees4%19%
Markdowns5%9%
Net margin+24%−6%

On the category report the product is a steady performer. By channel, one side is paying for the other, and only the net view tells you whether to grow the channel, fix its terms or step back from it.

EVERY SKU, BY REVENUE AND NET MARGIN

Illustrative. Plot the range by revenue and net margin and the loss-making lines a category average kept hidden separate clearly from the ones carrying the department.

04How we model it

Margin by product, channel and basket.

01

Pull the deductions together

Promotional spend, returns, shrink, markdowns and channel fees, gathered from the ledgers where they normally live apart.

02

Attribute to the product and channel

Each deduction lands on the SKU and channel that caused it, with TDABC for the fulfilment and handling cost behind it.

03

Build margin from list to net

Every line and channel carries a margin built down from shelf price to what actually stays, comparable across the range.

04

Rank and decide

Products and channels sort by net margin. The losers become candidates to reprice, renegotiate, repromote or delist, each with a number.

05What it changes

Assortment and channel calls on real margin.

Retailers who plan the range and the channel mix on net margin stop funding lines that lose on every sale and stop discounting the ones that quietly carry the category. The same model informs the buying terms, so negotiations with suppliers and channels start from the real cost of carrying a line.

The model is built on your data and handed over, so margin stays current as terms and promotions change.

Frequently asked questions

Why does headline retail margin mislead?
Headline margin is taken at the shelf, before trade and promotional spend, returns and shrink, markdowns and channel fees. Those deductions decide whether a product actually made money, and they differ sharply by product and channel, so a category average hides the lines and channels that lose.
How can the same product make money in one channel and lose in another?
The shelf margin is the same, but returns, marketplace commissions, promotional funding and fulfilment cost are not. A product with a healthy in-store margin can fall below break-even online once returns and channel fees are deducted.
What data does a retail margin model need?
Sales and cost by SKU, plus the deductions usually held separately: promotional spend, returns, markdowns, shrink and channel or marketplace fees. We map the gaps as part of the diagnostic rather than waiting for perfect data.
Will this tell us what to delist?
It tells you which products and channels destroy net margin and why. Many are fixed by repricing, renegotiating channel terms or changing how a line is promoted, rather than delisting; the model puts the number behind each option.
Start here

Find the lines that lose on every sale.

The Profit Check takes five minutes and no data upload. It points to where shelf margin and net margin are most likely to diverge in your range, and what it is worth to see clearly.

In short

In retail, cost to serve varies two to three times between accounts, stores or channels of the same revenue, because markdowns, returns, shrink, fulfilment and trade spend land unevenly. Costing only gross margin hides that roughly 20 to 40 percent of SKUs or accounts run below total cost once cost to serve is loaded. TDABC assigns those hidden costs to the store, channel and SKU that caused them, so every line shows its real net margin.

The AI angle

AI is arriving in the exact cost levers retail lives on.

Demand forecasting that trims markdowns and shrink, markdown optimisation that protects margin late in the season, and fulfilment automation that lowers the cost of an online order. None of those gains can be valued without a cost-to-serve baseline per channel and SKU. The retailers that win are the ones who already know their real net margin before the AI changes the workflow.

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