A discount needs more than a higher order count to pay off. Compare the money left after variable costs and extra campaign spending with what you expect to earn without the promotion over the same period. The worksheet below shows how many discounted orders would match that baseline, then asks whether your inventory and capacity can support them.
This is a single-product planning model, not a forecast or a complete profit statement. Its value is making the assumptions visible before a busy sale makes a weak offer look successful.
Key takeaways
- Revenue and contribution are different: more sales can leave less money to cover fixed costs and profit.
- Count payment fees, packaging, shipping subsidies and other variable costs, not only the product itself.
- Compare the promotion with a no-promotion scenario over the same period.
- Matching baseline contribution is parity, not proof of additional profit or customer demand.
What is left from each order?
Start with contribution per unit in dollars:
Selling price minus variable cost per unit = contribution per unit.
Variable costs are the costs that change with the units you sell. Depending on the business, include the product, packaging, payment fees, fulfillment and shipping you pay. Use the costs relevant to your offer and separate one-time campaign spending from costs already included per order.
Contribution is not net profit. Rent, salaries and other fixed costs still need to be covered. It is also different from a contribution margin percentage, which expresses that contribution as a share of the selling price.
The U.S. Small Business Administration’s break-even guidance uses fixed costs divided by price minus variable cost to estimate business break-even units. Our worksheet asks a narrower question: how many promotion orders would match a no-promotion contribution baseline? Do not confuse those two targets.
A fictional sale where revenue rises and contribution falls
Suppose a single product normally sells for $50 and has $30 in variable costs per unit. The founder’s no-promotion scenario is 100 orders during the comparison period. Those are fictional inputs, not results from a real store.
At the regular price, contribution is $20 per order, or $2,000 across 100 orders. A 20% discount lowers the selling price to $40. If variable cost stays at $30, contribution falls to $10 per order. Add $100 of extra campaign spending for the promotion.
- No promotion
- Orders: 100
- Revenue: $5,000
- Contribution before extra campaign spend: $2,000
- Extra campaign spend: $0
- Contribution after extra campaign spend: $2,000
- Discounted sale
- Orders: 150
- Revenue: $6,000
- Contribution before extra campaign spend: $1,500
- Extra campaign spend: $100
- Contribution after extra campaign spend: $1,400
- Discounted sale at parity
- Orders: 210
- Revenue: $8,400
- Contribution before extra campaign spend: $2,100
- Extra campaign spend: $100
- Contribution after extra campaign spend: $2,000
At 150 discounted orders, revenue is 20% higher than the baseline. Yet contribution after extra campaign spending is 30% lower. The busier sale has not matched the original scenario.
At 210 discounted orders, it matches the baseline contribution. That is 110 more orders than the baseline, not 110 total orders. The business has sold 110% more units just to reach parity under these assumptions.
Unchanged fixed costs are excluded from both sides of this comparison. They do not disappear from the business’s profit calculation. If the promotion needs extra labor, storage or other capacity costs, include those costs too.
How many discounted orders would match your baseline?
For a single product with positive contribution per discounted unit, use:
Required promotion units = (baseline units × regular contribution per unit + extra campaign cost) ÷ discounted contribution per unit.
Round up to the next whole unit when the calculation is not a whole number. In the example, ($2,000 + $100) ÷ $10 = 210 orders.
This is an editorial derivation from comparing the two contribution totals. It is not a separate SBA formula or a claim that those orders will materialize. It assumes all promotion units in the comparison sell at the discounted price, and the per-unit cost assumptions hold.
If discounted contribution is zero or negative, do not use this division to set an order target. Under the same assumptions, more discounted units cannot recover the baseline contribution. Rework the offer or cost model instead.
Copy this promotion comparison worksheet
- Product and comparison period: [Name and dates]
- Regular selling price: [Amount]
- Promoted selling price: [Amount]
- Regular variable cost per unit: [Cost breakdown]
- Promoted variable cost per unit: [Cost breakdown, including changed fees or shipping]
- No-promotion unit scenario: [Estimate and its basis]
- Promotion unit scenarios: [Lower, central and higher cases, with their basis]
- Extra campaign cost: [Only costs not already counted per unit]
- Baseline contribution: [Baseline units × regular unit contribution]
- Promotion contribution after extra campaign cost: [Promotion units × promoted unit contribution − extra campaign cost]
- Units required for contribution parity: [Formula above, if promoted unit contribution is positive]
- Saleable inventory and fulfillment limit: [What can actually be supplied]
- Returns and other missing costs: [Assumptions or costs needing confirmation]
- Decision: [Revise, hold or proceed within stated limits]
Use your records to choose the no-promotion scenario. A forecast is still an estimate, so try more than one baseline if it is uncertain. Comparing sales with a different period without considering seasonality or other changes can make the result misleading.
Do not double-count campaign spending or omit costs simply because they appear in another account. If a fee depends on the selling price, recalculate it for each scenario instead of assuming it stays constant.
Can you actually deliver the required orders?
An arithmetic target is not an inventory plan. Check how many saleable units are available, what replenishment depends on and how much fulfillment work the promotion would create.
Shopify’s Black Friday planning checklist recommends matching offers to inventory and margins and preparing fulfillment and returns. Those checks matter even when your sale is not tied to Black Friday.
The model also does not establish future customer value, repeat purchases or extra sales of other products. If those benefits are part of your rationale, state them separately as assumptions to test. Do not add an imagined future payoff to make today’s numbers pass.
What should you decide after filling it in?
If only the highest sales scenario reaches parity, that is a reason to question the offer, not declare it successful. You might reduce the discount, choose a different product, change the promotion’s reach or decide not to run it.
Some founders deliberately accept lower contribution to clear inventory or meet another goal. Make the trade-off explicit, including the cost and the limit you are willing to accept. The worksheet cannot choose that goal for you.
For a broader discussion of pricing approaches, read startup pricing and the value equation. This article is the narrower pre-promotion comparison, not a full pricing strategy.
Frequently asked questions
Is contribution the same as profit?
No. Contribution is what remains after variable costs. Fixed costs and other business expenses still matter when calculating profit.
Does matching the baseline mean the sale was profitable?
No. It means the model matches the no-promotion contribution scenario after extra campaign spending. It does not establish full business profit or what would actually have happened without the sale.
Can I use this for several products at once?
Not without adjusting the model for the product mix and different prices and costs. Start with separate product calculations and check how the combined promotion changes the assumptions.
What if returns or extra shipping change the cost per order?
Include those costs or show explicit scenarios for them. A model that omits material costs can overstate the contribution left from the promotion.
Method: original editorial worksheet and contribution comparison, with tool-checked fictional arithmetic and public SBA and Shopify guidance. No store test, sales forecast, measured result or accounting advice is claimed. Photos are illustrative.
