What It Is
LTV (Lifetime Value) and COCA (Cost of Customer Acquisition) are the two unit economics metrics that determine whether a business can sustainably grow. LTV measures the total profit generated by an average customer over the entire relationship. COCA measures the total cost of acquiring one new customer. Together, they answer the fundamental question: does each customer you acquire generate more value than they cost to win? Bill Aulet covers this as a critical step in Disciplined Entrepreneurship.
When to Use It
- When you have initial customers and need to evaluate whether the business model is sustainable.
- When deciding how much to spend on sales, marketing, and growth initiatives.
- When investors ask whether your unit economics "work" and you need to show the math.
- When choosing between pricing models (subscription vs. one-time, tiers, usage-based).
- Before scaling — poor unit economics at 100 customers become catastrophic at 10,000.
How It Works
Calculating LTV
LTV = (Revenue per Customer per Period) x (Gross Margin %) x (Average Customer Lifespan in Periods)
Or for subscription businesses:
LTV = (Average Revenue per User per Month) x (Gross Margin %) x (1 / Monthly Churn Rate)
Components to estimate:
- Revenue per period — What the customer pays you (monthly, annually, per transaction).
- Gross margin — Revenue minus the direct costs of serving that customer (hosting, support, COGS). Do not include overhead.
- Customer lifespan — How long the average customer stays before churning. For subscriptions, this is 1 divided by the churn rate.
- Expansion revenue — If customers tend to upgrade or buy more over time, include this in the per-period revenue.
Calculating COCA
COCA = Total Sales and Marketing Costs / Number of New Customers Acquired (in the same period)
Include everything:
- Marketing costs — Advertising, content, events, tools.
- Sales costs — Salaries, commissions, travel, CRM tools.
- Onboarding costs — If onboarding requires dedicated effort (training, implementation), include it.
The Ratio Test
- LTV:COCA >= 3:1 is the standard benchmark for a healthy business. This leaves room for overhead, R&D, and profit.
- LTV:COCA < 3:1 means either your pricing is too low, your acquisition costs are too high, or your churn is too fast.
- COCA recovery time < 18 months. Even if the ratio is good on a lifetime basis, if it takes three years to recoup the acquisition cost, you will run out of cash growing.
Key Principles
- Unit economics must work before you scale. Growth amplifies your economics — good or bad. If each customer is unprofitable, more customers means more losses.
- LTV is a prediction, not a fact. Early-stage companies must estimate lifespan and churn with limited data. State your assumptions explicitly and update them as you learn.
- COCA varies dramatically by channel. Inbound content marketing, outbound sales, partnerships, and paid ads all have different COCAs. Track them separately.
- Improving retention is usually cheaper than reducing acquisition cost. A small reduction in churn can dramatically increase LTV, improving the ratio without touching COCA.
- Both metrics change over time. As you scale, COCA often rises (you exhaust cheap channels) and LTV may shift (different customer segments have different lifespans). Monitor continuously.
Common Mistakes
- Using revenue instead of profit for LTV. LTV must be based on gross margin, not revenue. A customer who pays $100/month but costs $90/month to serve has an LTV based on $10/month, not $100.
- Excluding onboarding and implementation from COCA. If your product requires a hands-on setup process, that cost belongs in COCA. Ignoring it makes your unit economics look artificially healthy.
- Assuming early adopter economics will hold. Your first customers often come cheaply (founder's network, word of mouth). COCA for customers 101-1000 will likely be much higher.
Source
Bill Aulet, Disciplined Entrepreneurship (2013), Steps 18-19. LTV is covered in Step 18 and COCA in Step 19, with the relationship between them discussed as the validation of business model sustainability.
