How to Calculate Customer Lifetime Value (CLV)

This guide explains three methods (for shops, subscription businesses and project-based firms), where the input figures come from, and how to use CLV to set a sensible limit for acquisition costs.

What customer lifetime value tells you

CLV answers one question: how much is a new customer worth to your business over the whole relationship? That number is useful because most marketing decisions are really decisions about acquisition cost:

• How much can we pay for a lead or a new customer?
• Is a campaign that loses money on the first order still worth running?
• Which channel brings customers who stay longer and buy more?

Without CLV, these questions get answered with the first purchase only, which undervalues every business with repeat customers. With an optimistic CLV, they get answered too generously, which is how unprofitable campaigns get justified. The aim is a realistic, conservative figure.

Use gross profit, not revenue

The most common mistake is to calculate CLV from revenue. A customer who spends €1,000 with you over three years is not worth €1,000 if half of that went into goods, materials or subcontractors.

Gross profit = Revenue (net of VAT, after discounts and returns) − Direct costs of delivery

Direct costs are the costs that rise with each order: purchase price of goods, materials, payment fees, shipping you pay, external labour. Fixed costs such as rent or your own salary are not deducted here. They are covered by the sum of all gross profits.

If you only know your average gross margin as a percentage, multiply revenue by that margin. A shop with a 40 % gross margin earns €16.80 gross profit on a €42 order.

Method 1: Shops and repeat purchases

For online shops, retailers, restaurants, trades with regular service orders and anyone else whose customers buy repeatedly at irregular intervals:

CLV = Average gross profit per order × Orders per customer per year × Expected customer lifetime in years

You need three inputs:

Input	How to calculate it	Typical source
Average gross profit per order	Gross profit ÷ number of orders in the last 12 months	Shop system, accounting
Orders per customer per year	Orders in the last 12 months ÷ unique customers in the same period	Shop system, CRM
Expected lifetime in years	1 ÷ (1 − annual retention rate)	Customer list with first and last order date

The annual retention rate is the share of last year's customers who bought again this year. If 60 % come back, 40 % are lost each year, and the expected lifetime is 1 ÷ 0.4 = 2.5 years.

Worked example (hypothetical): A small online shop for specialty coffee has these figures for the last 12 months:

• 2,100 orders from 600 customers, so 3.5 orders per customer per year
• Average order value €42 (net), gross margin 40 %, so €16.80 gross profit per order
• 60 % of last year's customers ordered again, so an expected lifetime of 2.5 years

CLV = €16.80 × 3.5 × 2.5 = €147

A customer generates €58.80 gross profit per year and €147 over the relationship. Note how different this is from the first order (€16.80) and from revenue over the lifetime (€42 × 3.5 × 2.5 = €367.50).

Method 2: Subscriptions, retainers and contracts

For businesses with recurring monthly fees, such as software, maintenance contracts, memberships or agency retainers, CLV follows from the churn rate:

CLV = Monthly gross profit per customer ÷ Monthly churn rate

The monthly churn rate is the share of customers who cancel in a month: customers lost in the month ÷ customers at the start of the month. Because small numbers fluctuate, use the average of the last six or twelve months.

Worked example (hypothetical): An IT service provider sells a support contract for €250 per month. Delivering it costs about 45 % of the fee (technician time, tools), so the gross margin is 55 % and the monthly gross profit per customer is €137.50. On average, 4 of 160 customers cancel per month, a churn rate of 2.5 %.

• Expected lifetime: 1 ÷ 0.025 = 40 months
• CLV = €137.50 ÷ 0.025 = €5,500

Forty months is more than three years, and nobody knows what the market looks like by then. A conservative variant caps the lifetime, for example at 36 months: €137.50 × 36 = €4,950. Use the capped figure for budget decisions and note the uncapped one as an upper bound.

Method 3: Project businesses and B2B with irregular orders

If your customers order projects of very different sizes at irregular intervals, as with agencies, engineering firms, joiners or B2B suppliers, averages and churn rates are hard to define. The more reliable approach is to look back at a cohort: all customers whose first order fell in the same year.

Worked example (hypothetical): A joinery firm won 40 new customers in 2023 and adds up the gross profit these 40 customers generated in each year since:

Year	Gross profit of the 2023 cohort	Per customer	Cumulative per customer
2023	€48,000	€1,200	€1,200
2024	€22,000	€550	€1,750
2025	€14,000	€350	€2,100

The three-year CLV of a new customer is about €2,100. This figure is measured, not assumed, which makes it the most trustworthy of the three methods. Its weakness is that it describes customers you won in the past. If your offer or pricing has changed since, adjust it.

With project businesses, also check the median in addition to the average. If one customer in the cohort placed a single €30,000 order, the average gets pulled up and no longer describes a typical customer. Either show that customer separately or work with the median for budget decisions.

Where the numbers come from

Figure	Best source	If you do not have it
Revenue and orders per customer	Shop system, invoicing software, CRM	Export invoices with customer numbers to a spreadsheet
Gross margin	Accounting, product calculation	Use your average margin from the annual accounts
Retention or churn	Customer list with first and last order date	Count how many of last year's customers ordered again
Cohorts	CRM or accounting with customer start date	Use the date of the first invoice per customer

A clean customer number in every system is the foundation. If the same company appears as three customers because the name was typed differently, retention looks worse than it is.

Using CLV to set your acquisition budget

CLV becomes useful when you put it next to customer acquisition cost (CAC). Our guide on how to calculate customer acquisition cost covers the CAC side, including the CAC payback period and the LTV:CAC ratio.

Three practical uses:

1. A ceiling for CAC. A ratio of about 3 : 1 between CLV and CAC is often quoted as a rule of thumb. For the coffee shop, that would mean a target CAC of around €49 (€147 ÷ 3). It is an orientation, not a law; a business with tight cash may want a lower CAC, a business with very loyal customers may accept a higher one.

2. How long the money is tied up. If the shop pays €40 to acquire a customer, the first order (€16.80 gross profit) does not cover it. It takes €40 ÷ €16.80 ≈ 2.4 orders, which at 3.5 orders per year means about eight months. That is acceptable only if the business can pre-finance those months.

3. Realistic targets for ads. Break-even ROAS on the first order is 1 ÷ gross margin, in the example 1 ÷ 0.4 = 2.5. If repeat purchases are reliable, you can accept a lower ROAS on the first order, but only to the extent your retention data supports it. The marketing ROI, ROAS and CAC calculator shows your break-even ROAS and CAC for a campaign; our article on ROAS vs ROI explains why the first-purchase view understates repeat business.

If you plan paid search, the same logic sets your maximum cost per customer in the Google Ads budget calculation.

CLV by channel and segment

An average CLV hides big differences. Customers from referrals often stay longer than customers from a discount campaign; business customers may order more often than private ones. If your CRM records where customers came from, calculate CLV per segment:

Acquisition channel	Customers	Orders per year	Expected lifetime	CLV (gross profit)
Google Ads	220	3.5	2.5 years	€147.00
Newsletter sign-up	180	4.5	3.5 years	€264.60
Discount voucher partner	200	2.5	1.5 years	€63.00

The figures are hypothetical, based on the coffee shop's €16.80 gross profit per order, and together they roughly reproduce its overall averages. Such a table often changes budget priorities: a channel with a higher CAC can still be the better one if its customers are worth twice as much.

Common mistakes

Using revenue instead of gross profit. It inflates CLV and leads to acquisition costs you cannot afford.

Including VAT. VAT is not your money. Use net figures.

Overestimating lifetime. Young businesses especially tend to assume customers will stay for many years. Cap the lifetime and update it once you have real retention data.

Ignoring the cost to serve. Discounts, returns, free shipping and support time reduce gross profit. If a customer group causes a lot of them, its CLV is lower than the average suggests.

Mixing very different customers. One average for private and business customers, or for small and large accounts, describes nobody. Segment where the differences are large.

Treating CLV as a fixed number. Prices, margins and retention change. Recalculate quarterly and keep the history, just like your other marketing KPIs.

Checklist

• Gross profit per order or per month calculated from net revenue minus direct costs
• Purchase frequency and retention (or churn) taken from the last 12 months of real data
• Method chosen to fit the business model: repeat purchases, subscription or cohort
• Lifetime capped at a conservative period, uncapped value noted as an upper bound
• Median checked against the average for project businesses
• CLV compared with CAC, payback period and break-even ROAS
• CLV calculated per channel or segment where customer numbers allow it
• Recalculated every quarter and recorded next to previous values

Summary

Customer lifetime value is the gross profit a customer brings you over the whole relationship. For repeat purchases, multiply gross profit per order by orders per year and expected years; for subscriptions, divide monthly gross profit by the monthly churn rate; for project businesses, measure what past cohorts actually generated. Keep the figure conservative, segment it where customers differ, and use it to set a ceiling for what you pay to win a new customer.