Resin up 8%—hold EUR 45 list or reprice now?
Recalculate contribution first. If variable rises EUR 2, contribution drops from EUR 17 to EUR 15—break-even rises ~200 units on EUR 62k fixed. Reprice or accept lower profit explicitly.
ZBI Business Control Library
Contribution Margin
Contribution Margin: plain-English definition, formula, worked example, how to interpret the result, peer-based benchmark guidance, common mistakes, and management actions in the ZBI Business Control Library.
What is Contribution Margin?
Contribution margin is selling price minus variable cost per unit—the euros each unit puts toward fixed costs and profit. SKU priced EUR 45 with EUR 28 variable cost contributes EUR 17. I use it for special orders, product rationalisation, and break-even because it strips out allocated rent and salaried overhead that do not move with one extra unit. Confuse contribution with gross margin and you reject incremental business that pays the shift, or accept orders that bleed cash on every piece.
Why Contribution Margin matters
Fixed costs do not shrink when volume drops—you need enough contribution units to cover EUR 62,000 monthly fixed on the line. Sales quoting below variable cost to 'keep the line busy' erodes cash unless the board documented a strategic reason. When resin rises 8% on a hero SKU, contribution moves weeks before net margin shows the damage—procurement and commercial must see the same matrix monthly. Customers feel contribution problems as sudden price increases after you absorbed material cost too long. The plant feels them as shift cuts when contribution no longer covers fixed at actual volume.
Formula and variables
Contribution Margin = Selling Price − Variable Cost per Unit
Selling price — net of routine variable discounts if that is your policy.
Variable cost — materials, direct labour, variable logistics, commissions—not allocated factory rent.
Excel: =B2-B3; ratio =IFERROR(B4/B2*100,0).
Real business example
Balkan Components d.o.o., a B2B supplier in Belgrade, prices SKU A at EUR 45. Variable material EUR 18, direct labour EUR 6, variable packaging and freight EUR 4 → variable EUR 28. Contribution margin EUR 17; ratio 37.8%. Fixed costs on the line EUR 62,000 monthly; break-even ≈ 3,647 units if only SKU A sold. Actual mix includes lower-contribution SKU B—the owner reviews portfolio contribution before holding list price while resin rose 8%.
How to interpret the result
Positive contribution per unit is necessary; it is not sufficient for profit.
- Negative contribution SKUs need exit, repricing, or explicit strategic subsidy.
- Do not treat allocated overhead as variable in special-order tests.
- Contribution ratio compares EUR 17 on EUR 45 to EUR 9 on EUR 22 fairly.
- Use net price after routine rebates, not list, in the formula.
Benchmark context
Contribution ratios differ by category—software services higher than commodity hardware. Benchmark against your SKU portfolio bands and pricing policy targets, not a universal 40%. Compare to prior year before input-cost inflation. Peer gross margin disclosures need careful mapping—your contribution definition may exclude production overhead theirs includes.
Red flags
- Contribution ratio below 30% on A-class SKUs after material index move—price or spec change required.
- Sales exception pricing below variable cost rising month-on-month—cash negative on incremental units.
- Break-even 3,647 units but actual mix weighted toward SKU B—line under-recovers fixed despite 'busy' plant.
- Contribution held but volume down 20%—fixed EUR 62k unchanged; profit gap widening.
- Discounting erodes contribution 2+ points while revenue target met—volume bought at loss of margin.
Common mistakes
- Labelling fixed labour as variable because overtime fluctuates.
- Using list price while every customer takes standard rebates.
- Accepting incremental orders below variable cost without board-approved rationale.
- Strong hero SKU contribution masking weak tail in blended reports.
- Confusing contribution margin with markup on cost.
What should management do next?
- Maintain contribution matrix by SKU updated monthly with material index links.
- Require contribution check on every exception price below published floor.
- Rank customers by total contribution dollars quarterly, not revenue.
- Run break-even on contribution changes before permanent price holds.
- Train sales on contribution vs gross margin before quarterly price reviews.
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FAQ
Customer wants 5,000 units at EUR 40—below list but above variable EUR 28. Accept?
Contribution EUR 12 × 5,000 = EUR 60,000 toward EUR 62k fixed—short on fixed recovery alone. Accept only if capacity is idle and no better order exists.
Why does finance reject an order sales calls 'profitable'?
Full-cost profit includes allocated overhead; contribution test asks whether the order pays variable cost plus incremental fixed. Different question.
Should I drop SKU B if contribution is positive but low?
Compare SKU B contribution hours to line capacity and customer retention value. Low contribution plus high service cost is exit criteria.
How do I set exception pricing authority for sales?
Set floor at variable plus minimum contribution per unit; regional manager approval below floor, CFO below variable.
Summary
Contribution margin shows what each unit pays toward fixed costs and profit after variable spend. Use it for pricing floors, mix decisions, and break-even—with consistent variable definitions.
Reviewed by ZBI Business Control Library · Last updated 2026-06-15