Unit economics: why every owner should understand it
Unit economics shows the economics of a single unit of your business: one customer, one order, one subscription. It is the key metric that tells the truth about your business model.
In practice it answers one question: can you make money on EVERY customer, or only on average? If your unit economics is poor, you can grow revenue while losing money. Plenty of startups that looked successful ultimately went bankrupt: the investor cash ran out before the company ever learned how to make money.
We have seen companies with ₽500M in annual revenue that were still unprofitable, because the unit economics simply did not add up. And we have seen companies with ₽20M in revenue that were highly profitable, because their economics was sound.
Key unit-economics metrics
1. CAC — cost to acquire one customer
Definition: how much you spent to acquire one paying customer.
Formula: (Marketing spend) / (Number of new customers acquired in the period)
E-commerce example:
- Spent ₽500K on marketing in a month
- Acquired 200 new customers
- CAC = 500,000 / 200 = ₽2,500 per customer
SaaS example:
- Spent ₽1M on marketing in a month
- Acquired 100 new paying subscribers
- CAC = 1,000,000 / 100 = ₽10,000 per subscriber
What to include in marketing spend:
- Marketer / marketing manager salary
- Sales team salaries (if you have a sales force)
- Advertising (Facebook, Google, billboards, paid search)
- Tools (CRM, analytics, email marketing)
- Content (video, blog, design)
- Public relations and press
- Events and conferences
What not to include:
- The owner's own salary
- Office (that's an operating cost)
- Product development
2. LTV (Lifetime Value) — total customer value over the full relationship
Definition: how much the company earns from one customer over the entire relationship (net of variable costs).
Formula for one-off purchases: Average order value × Average number of purchases
Example: e-commerce sneakers
- Average order value: ₽5,000 (one pair of sneakers)
- Average lifetime purchases: 2 (a customer buys roughly 2 pairs)
- Gross LTV = 5,000 × 2 = ₽10,000
- Less variable costs (shipping, marketplace commission, returns): ₽2,000
- Net LTV = ₽8,000
Formula for subscriptions: (Average monthly revenue − Variable costs) × Average customer lifetime in months
Example: SaaS platform
- Average subscription price: ₽10,000/month
- Variable cost to serve (cloud, support): ₽2,000/month
- Average retention (lifetime): 18 months (the average customer stays 1.5 years)
- Average monthly revenue per customer: 10,000 − 2,000 = ₽8,000
- LTV = 8,000 × 18 = ₽144,000
Important: use gross margin, not net profit
LTV should reflect only variable costs (those that scale with volume), not operating costs (salaries, office). Operating costs are deducted later, when you look at margin at the whole-company level.
3. LTV:CAC ratio — the headline health metric
Definition: the ratio of customer value to the cost of acquiring that customer.
Formula: LTV / CAC
Benchmarks:
- Minimum 2:1 (LTV twice the CAC) — the model makes money, but with little buffer
- Good: 3:1 or higher (LTV 3×+ the CAC) — the company is healthy
- Excellent: 5:1 or higher — a highly profitable business
Example:
- CAC = 2,500 (from the example above)
- LTV = 8,000 (from the one-off-purchase example above)
- LTV:CAC = 8,000 / 2,500 = 3.2 : 1 (good)
SaaS example:
- CAC = 10,000
- LTV = 144,000
- LTV:CAC = 144,000 / 10,000 = 14.4 : 1 (excellent)
If LTV:CAC is below 2:1: stop. The business model isn't working yet — it's too early to pour money into marketing and scale. First raise LTV or cut CAC.
4. CM (Contribution Margin) — margin per unit
Definition: what share of the price remains after variable costs.
Formula: (Price − Variable costs) / Price
Example: e-commerce product
- Price: ₽1,000
- Cost of goods: ₽300
- Shipping (on us): ₽100
- Payment-processing fee: ₽30
- Returns (on average): ₽30
- Total variable costs: ₽460
- CM = (1,000 − 460) / 1,000 = 54%
CM benchmarks:
- Retail: 30–40% (the rest goes to payroll and rent)
- E-commerce: 40–60%
- SaaS: 60–80% (almost no variable costs)
- Services: 50–70%
If CM is below the benchmark: revisit pricing, lower the cost of goods, or move to higher-priced products.
5. Payback period
Definition: how many months it takes for the revenue from a customer to recoup the cost of acquiring them.
Formula: CAC / (Average monthly revenue per customer after variable costs)
Example:
- CAC = ₽2,500 (from the example above)
- Average monthly revenue = ₽5,000 (average order value) × 2 lifetime purchases / (12 months × 2 years) ≈ ₽400/month
- Payback period = 2,500 / 400 = 6.2 months
Payback-period benchmarks:
- Minimum: 3–6 months (fast payback)
- Good: 6–12 months
- Acceptable: 12–18 months
- Poor: 24+ months (high risk that the customer never pays back)
Why payback matters: if a customer takes 24+ months to pay back, you depend on them not leaving. With high churn, the customer leaves before they ever pay back.
6. Churn rate — the share of customers who leave
Definition: the share of customers who leave each month (for subscriptions) or each year (for services).
Formula: (Customers lost in the month) / (Customers at the start of the month)
SaaS example:
- Start of month: 1,000 subscribers
- Lost: 50 subscribers
- Churn rate = 50 / 1,000 = 5% per month (this is bad — revenue is falling)
Churn-rate benchmarks:
- Excellent: below 2–3% per month
- Good: 3–5%
- Poor: 5–10%
- Critical: above 10% (the business is collapsing)
How this drives LTV: at 5% monthly churn, the average customer lifetime is just 20 months. At 2% churn — 50 months.
Step-by-step unit-economics calculation for your business
Step 1: Choose the unit of analysis
- B2C e-commerce: one order (not one customer)
- SaaS: one paying user per month
- B2B services: one contract or one project
- Marketplace: one transaction
Step 2: Calculate CAC
For the last month / quarter / year:
- List all marketing costs
- Add them up
- Count how many new customers you acquired
- CAC = Total spend / Number of new customers
Step 3: Calculate average revenue per customer
- Take revenue from the last 3–6 months
- Divide by the number of customers in that period
- That's your average monthly or per-period revenue
Step 4: Calculate variable costs
- Shipping, production, fees, support, returns
- Add them up
- Divide by average revenue (this gives you a % of revenue)
Step 5: Calculate LTV
- For one-off purchases: average number of repeat purchases × (average order value − variable costs)
- For subscriptions: (subscription price − variable costs) × average customer lifetime in months
Step 6: Calculate the ratio and payback
- LTV / CAC = should be at least 3:1
- Payback = CAC / (average monthly revenue − variable costs)
Red flags in unit economics
- LTV:CAC below 2:1: a signal to stop. The model doesn't add up — it's too early to grow and invest; fix the economics first
- Payback above 24 months: high risk. You depend on the customer not leaving
- CM below 20%: no margin buffer. The slightest rise in costs tips you into the red
- Churn above 5% per month: customers leave fast. Even if LTV:CAC looks good now, at this churn it will erode
- CAC growing faster than revenue: a sign the market is saturating. Rising CAC means cheap traffic may soon run out
How to improve unit economics
Lever 1: Lower CAC (acquisition cost)
Methods:
- Organic growth: referrals, content, SEO. Cheaper than paid advertising. Acquisition through referrals costs about 70% less than paid ads
- Conversion optimization: improve the site, landing page, and sales funnel. Higher conversion means you need less traffic
- Partner deals: find 2–3 large partners willing to recommend you
- B2B sales: if you're B2B, outreach is often cheaper than advertising. One rep at ₽200K/month can bring in ₽10M in revenue
Result: cutting CAC by 30–50% gives the business a new lease of life. Lower CAC instantly improves LTV:CAC.
Lever 2: Raise LTV (customer value)
Methods:
- Extend customer lifetime: improve onboarding, product quality, and support. If lifetime grows from 12 to 18 months, LTV rises by 50%
- Raise the average order value: upsell (offer a higher-tier plan), cross-sell (add-on services), raise prices for new customers
- Increase purchase frequency: email marketing, reminders, a loyalty program
Example: a SaaS raised prices 20% (losing 5% of customers) → higher revenue, LTV up 15%
Lever 3: Reduce variable costs
Methods:
- Lower the cost of goods: negotiate with suppliers, find production savings
- Cut shipping costs: in-house logistics instead of courier services, route optimization
- Cut cost to serve: automation, self-service, community instead of one-to-one support
Result: a 20% drop in variable costs raises the contribution margin and lifts LTV.
Unit-economics examples across business types
E-commerce (average order ₽3,000): CAC = 1,500, LTV = 6,000, ratio = 4:1 (good)
SaaS (subscription ₽20K/month): CAC = ₽50K, LTV = ₽200K, ratio = 4:1 (good)
Consulting (contract ₽2M): CAC = ₽200K, LTV = ₽4M, ratio = 20:1 (excellent)
Marketplace (10% take rate per deal): CAC = 1,000, LTV = 3,000, ratio = 3:1 (acceptable)
A bad example (why not to invest): a startup acquires customers for 5,000, customer value is 6,000, ratio 1.2:1. You must NOT scale. Fix it first.
How to track unit economics
- Monthly: calculate CAC, LTV, and the ratio for customers acquired that month
- Watch the trends: is LTV rising? Is CAC falling? Is the ratio improving?
- By channel: which acquisition channel delivers the best unit economics (organic vs. paid vs. partners)?
- By cohort: has the unit economics shifted for customers acquired in different months?
Conclusion
Unit economics is the heart of your business. If it's healthy (LTV:CAC of at least 3:1), you can afford to grow. If it's weak (below 2:1), put the model in order first and scale only after that. Every calculation starts with a simple table: even a rough cut on your own numbers usually shows immediately where the model is leaking.
Keep one thing in mind: revenue can be anything, but with weak unit economics, growth only multiplies the losses. And it's one of the first things investors look at.