How to Calculate Your Customer Lifetime Value

Customer Lifetime Value, or CLV, is the total profit a single customer brings you across the whole time they do business with you. 

The basic formula is simple: average purchase value, multiplied by how many times they buy a year, multiplied by how many years they stay, and then multiplied by your profit margin so you are counting profit and not just revenue. 

Get this number right and it changes how much you are willing to spend to win a customer, and how hard you fight to keep one.

Let me show you how to work it out, with a real example, and then I want to talk about what to do when you run a business where most people only ever buy from you once. Because that is where this number gets interesting, and where word of mouth becomes the whole game.

The formula, plainly

Here is the version I want you to use:

CLV = Average purchase value x Purchases per year x Years they stay x Profit margin

That last step matters and most people skip it. A customer who spends $10,000 with you over their lifetime is not worth $10,000 to you. If your margin is 10%, they are worth $1,000. As the team at ACXPA here in Australia put it, the basic revenue formula is a quick approximation, and you should graduate to the margin-aware version for any decision you would actually stake money on. So we count profit, not revenue.

A worked example

Let us say you run a business, and your numbers look like this:

1. Average purchase value: a customer spends $400 each time they buy.

2. Purchases per year: they come back 3 times a year. So $1,200 a year.

3. Years they stay: on average, a customer sticks with you for 5 years.

4. Profit margin: your net margin is 15%.

Now we put it together.

$400 x 3 purchases x 5 years = $6,000 in lifetime revenue.

Then the step nobody likes: $6,000 x 15% margin = $900.

So your real Customer Lifetime Value is $900, not $6,000. That $900 is what one customer is genuinely worth to your bottom line. 

And once you know that, you know something powerful. You now know roughly how much you can afford to spend to win a new customer, your acquisition cost, and still come out ahead. If it costs you $300 to win a customer worth $900, that is a good trade. If it costs you $900 to win a customer worth $900, you are working for nothing.

This is exactly the kind of number a Business Analysis digs out, because most owners have never sat down and worked it out, and it quietly governs whether their marketing makes money or burns it.

Why retention matters more than you think

Here is the part that should make you care about keeping customers, not just winning them.

The maths is brutally lopsided. Acquiring a new customer can cost 5 to 25 times more than keeping an existing one, according to Harvard Business Review. And when you lift retention by just 5%, profits have been shown to rise between 25% and 95%. Read that again. A 5% improvement in how many customers stay can nearly double your profit, because every year a customer stays adds another full slice to their lifetime value at almost no acquisition cost.

In the worked example above, if you could keep customers for 7 years instead of 5, the same customer jumps from $900 to $1,260 in value. Same customer. Same spend. You just held on to them longer.

There is good Australian evidence for why they stay, too. One 2025 service-industry report found 88% of Australian customers say a great service experience makes them more likely to buy again, which feeds straight into lifetime value. Service is not soft. Service is the lever on the years-they-stay part of the equation.

But what if your customers only ever buy once?

This is the question I get from a lot of business owners and it is a fair one. 

The CLV formula above assumes people come back. So what do you do if you run a one-off business, a wedding photographer, a celebrant, a removalist, a builder, a tour operator selling a bucket-list experience, the kind of thing most people buy from you exactly once in their life?

For a true one-off business, the standard CLV frame is less useful, and referral value matters far more. That is straight from the ACXPA glossary, and it is the honest answer. When a customer will not buy again themselves, their real value to you is not their repeat purchases. It is the customers they send you.

So the lifetime value of a one-off customer is the profit from their single purchase, plus the profit from everyone they refer to you. And for a one-off business, that referral number is not a nice extra. It is the whole growth engine.

The data on this is strong, and it is worth knowing.

• 92% of consumers trust referrals from people they know more than any form of advertising (Nielsen). For a one-off business, a happy customer telling their mate is the most powerful marketing you will ever have.

• Referred customers are worth more. Their lifetime value runs about 16% higher than non-referred customers, and they churn 18% less (Wharton and Harvard Business Review).

• The average order value of referred customers and brand advocates is around 150% higher than other customers (Forrester).

• Word of mouth can generate roughly five times more sales than paid media, according to figures pulled together from McKinsey.

So if you run a one-off business, here is how I suggest you think about lifetime value.

Let us say you are a wedding photographer. A couple pays you $4,000 for their wedding, and your margin is 30%, so that booking is worth $1,200 in profit. They will almost certainly never book a wedding with you again. On the basic formula, their lifetime value is $1,200 and that is the end of it.

But weddings are one of the most referral-driven businesses there is. Their guests see your work. Their friends ask who shot it. Let us say that one happy couple, over the next few years, sends you two more bookings through word of mouth. Suddenly that one customer is not worth $1,200. They are worth $1,200 plus two more bookings at $1,200 each, which is $3,600 in total. You tripled the value of that customer, and you did it through referral, not repeat purchase.

That is why, for a one-off business, the most important work is not chasing repeat sales that will never come. It is making the single experience so good that people cannot help talking about it, and then giving them an easy, rewarding reason to send people your way.

Turning that into something practical

Australia Post puts it well: your existing clients are often your best salespeople, because people trust a recommendation from someone they know. A simple referral scheme, where you reward a past customer for sending you a new one, does two jobs at once. It brings in new customers at a very low cost, and it makes your past customers feel valued.

For a one-off business, I suggest you do three things:

1. Make the single experience genuinely better than people expect. Word of mouth only fires when you exceed expectations, not when you meet them.

2. Ask for the referral, and make it easy. Most happy customers will gladly recommend you. Very few will think to do it unless you prompt them.

3. Reward it. A discount, a gift, a thank you that means something. Double-sided rewards, where both the referrer and the new customer get something, are now the most common kind for a reason.

The short version

CLV = average purchase value x purchases per year x years they stay x profit margin. Always finish with the margin, so you are counting profit, not revenue.

Worked example: $400 x 3 x 5 years x 15% margin = $900 real lifetime value, not $6,000.Retention is the cheapest growth there is. Winning a customer costs 5 to 25 times more than keeping one, and a 5% lift in retention can raise profit 25% to 95%.

For a one-off business, the standard formula falls short. A customer's real value is their one purchase plus everyone they refer. Referred customers are worth 16% more, churn 18% less, and 92% of people trust a recommendation from someone they know. For a one-off business, word of mouth is the entire growth engine.

For me, the number that matters is not how many customers you can win. It is how much each one is truly worth once you count the margin and the mates they bring with them. Most owners have never worked that out, and it is quietly deciding whether their marketing makes them money.

If you want to work out your real Customer Lifetime Value, and build the referral engine to lift it, the starting point is a Business Analysis. Speak to Sarah today at sarahcolgate.com.au.

For more, read Maximise the Lifetime Value of Every Client, What Are Your Customers Really Buying?, and How To Use Customer Feedback As A Growth Tool.