Why unit economics come first
Every growth decision in ecommerce, from advertising budgets to free shipping thresholds, rests on one question: does a typical order make money? If it does, growth multiplies profit. If it does not, growth multiplies losses, and faster growth multiplies them faster.
Unit economics answer that question. They are not an accounting exercise for the finance team. They are the operating manual for marketing, because they tell you how much you can pay for a customer, which products to push, which offers to run and which channels to scale.
Revenue tells you how big the business is. Contribution tells you whether it should be bigger.
The price waterfall
Start with the price a customer sees and subtract, layer by layer, every cost that varies with the order. What remains at each level tells you something different.
Fig. 01 · Stack
Tap to explore
From list price to contribution
List price
What the product page shows
Net selling price
After discounts, coupons and taxes collected for the government
Less product cost
Manufacturing or purchase cost, inbound freight, packaging
Less fulfilment and payment
Pick, pack, shipping, payment gateway or COD fees
Less returns and RTO
Expected cost of failed deliveries and returned items
Less marketing
Acquisition and promotional cost attributed to the order
CM1, CM2 and CM3
Many ecommerce teams use three contribution levels. The names are conventions rather than standards, so define them clearly in your own business. A common version follows.
Fig. 02 · Hierarchy
Tap to explore
Three levels of contribution margin
01 · CM3: after marketing
Does acquiring and serving this order make money?
02 · CM2: after fulfilment, payment, returns
Does delivering this order make money before marketing?
03 · CM1: after product cost
Is the product priced well relative to what it costs?
- CM1 is net selling price minus product cost. It tests pricing and sourcing.
- CM2 subtracts shipping, packaging, payment fees, and the expected cost of returns and RTO. It tests operations and the delivery model.
- CM3 subtracts marketing cost. It tests whether the business can grow profitably at its current acquisition cost.
A business can have healthy CM1 and still fail at CM2 if shipping and returns are expensive, or healthy CM2 and fail at CM3 if acquisition costs are too high. Knowing which level breaks tells you which team needs to act.
Calculate your own
Calculator
Contribution margin per order
Illustration only: defaults are invented. Enter averages for a typical order.
CM1
₹780
After product cost.
= price - cogs
CM2
₹550
After fulfilment, payment and returns.
= price - cogs - ship - pay - ret
CM3
₹250
After marketing.
= price - cogs - ship - pay - ret - mkt
CM3 as share of price
20.8%
Negative means each order loses money at current marketing cost.
= (price - cogs - ship - pay - ret - mkt) / price
Defaults are illustrations. Use your own numbers. Nothing you enter leaves this page.
Expected returns and RTO cost is the easiest line to get wrong. Estimate it as the probability of a failed delivery or return multiplied by its cost, plus any lost revenue on items that cannot be resold. See reducing RTO.
From order to customer
Order-level economics tell only half the story. Most brands lose money or barely break even on the first order once acquisition cost is included, and earn their profit on repeat orders, which carry little or no acquisition cost.
So the second view is customer-level: the contribution a customer generates over a period, minus the cost of acquiring them. That is the basis of CAC and LTV and of payback period, the time it takes for a customer’s cumulative contribution to repay their acquisition cost.
| View | Question it answers | Main lever |
|---|---|---|
| CM1 per order | Is the product priced right? | Price, sourcing, pack size |
| CM2 per order | Can we deliver it profitably? | Shipping rates, RTO, returns, payment mix |
| CM3 per order | Does marketing pay for itself on this order? | Acquisition cost, conversion rate |
| Customer contribution over a period | Is a customer worth acquiring? | Retention, repeat rate, order value |
| Payback period | How long is our cash at risk? | All of the above, plus cash planning |
Indian specifics
In India, three features change the maths. Cash on delivery introduces RTO risk, which must be priced into CM2. GST is collected on behalf of the government and should be excluded from revenue when calculating margins. And marketplace and quick-commerce routes carry commissions and fees that make their unit economics very different from the brand’s own site.
Calculate unit economics separately for each route, and for prepaid and COD orders, rather than blending them. A blended number can hide a route that loses money behind one that subsidises it. See marketplace marketing.
Using unit economics to make decisions
- Set acquisition limits. The maximum CAC follows from customer contribution and your acceptable payback period.
- Choose which products to advertise. Low-CM2 products may not justify paid promotion at all.
- Design offers. Free shipping thresholds and bundles should raise CM2 per order, not just revenue.
- Pick channels. Compare CM3 by channel, using delivered orders.
- Prioritise operations. If CM2 is weak, shipping and RTO work may beat any marketing change.
Self-diagnostic
0/5How solid are your unit economics?
A quick check of the numbers you rely on.
01Do you calculate contribution excluding GST from revenue?
If yes: Your margins are on the right base. If no: Recalculate; including tax overstates margin.02Does CM2 include the expected cost of RTO and returns?
If yes: You are seeing the real delivered economics. If no: Add it; in COD-heavy businesses this line can be large.03Do you calculate unit economics separately by sales route?
If yes: You can see which routes subsidise others. If no: Split own site, marketplaces and quick commerce.04Do you know your payback period on new customers?
If yes: Use it to plan cash and acquisition limits. If no: Build it from cohort data; it governs how fast you can grow.05Is CM3 on first orders reviewed monthly?
If yes: You will catch rising acquisition costs early. If no: Add it to the monthly review.
Fixed costs and the path to profit
Positive contribution is necessary but not sufficient. Contribution must also cover fixed costs: salaries, rent, software, agency retainers and brand investment. The number of orders needed to cover them is the break-even volume, and it is worth knowing for planning.
Illustration: if fixed costs are ₹10,00,000 a month and CM3 per order is ₹200, the business needs 5,000 orders a month to break even. Raising CM3 to ₹250 lowers that to 4,000. Small improvements in contribution per order often move break-even more than heroic volume targets.
This is also why order value matters. Many costs, such as shipping and payment fees, are partly fixed per order, so larger baskets usually carry better contribution. See average order value.
Common errors
- Using list price instead of net selling price after discounts.
- Leaving out packaging, payment fees or COD charges.
- Counting orders placed rather than orders delivered and kept.
- Allocating no marketing cost to orders because they came through ‘organic’ routes that were in fact paid for elsewhere.
- Treating fixed costs such as salaries as variable, which makes small orders look worse than they are, or the reverse.
Key takeaways
- 01Unit economics show whether a typical order and a typical customer make money after variable costs.
- 02Build contribution in layers: CM1 after product, CM2 after fulfilment, payment and returns, CM3 after marketing.
- 03In COD-heavy markets, include RTO in CM2 and exclude GST from revenue.
- 04Calculate unit economics separately by sales route and payment mode.
- 05Use the numbers to set acquisition limits, choose products to advertise and design offers.
Frequently asked
- What are unit economics in ecommerce?
- Unit economics describe the revenue and costs associated with a single order or a single customer. In ecommerce they usually focus on contribution margin per order, after product, fulfilment, payment, returns and marketing costs, and on customer-level measures such as lifetime contribution and payback period.
- What is contribution margin in ecommerce?
- Contribution margin is what remains from an order’s net revenue after subtracting the costs that vary with that order. It is often shown in levels, such as CM1 after product cost, CM2 after fulfilment and returns, and CM3 after marketing. It shows how much each order contributes to fixed costs and profit.
- What is the difference between CM1, CM2 and CM3?
- CM1 is net revenue minus product cost. CM2 further subtracts fulfilment, shipping, payment fees and returns. CM3 further subtracts marketing cost. Definitions vary between companies, so document yours. Each level shows whether pricing, operations or acquisition is the weak point.
- How do returns and RTO affect unit economics?
- They add costs such as reverse shipping, handling and damaged stock, and they remove revenue that was counted when the order was placed. Include the expected cost per order, based on your actual rates, in CM2. Ignoring them can make a loss-making business look profitable.
- How do I improve ecommerce unit economics?
- Raise net selling price through better positioning or fewer discounts, reduce product cost, raise order value with bundles and thresholds, cut shipping costs, reduce RTO and returns, shift towards prepaid, lower acquisition cost through better conversion and creative, and increase repeat purchase so acquisition cost is spread over more orders.
Published by Fabulous.Media, a network of specialist marketing agencies. Updated 9 October 2026. Platform features change often; check current official documentation before acting on platform-specific detail.
