How Do I Figure Out What a Customer Is Worth to My Small Business?

By Bill Stilwell · Last reviewed October 18, 2026

The short answer

Customer lifetime value (CLV) is the profit a typical customer brings you over the whole time they buy from you. Multiply the average sale by how often they buy and how long they stay. Then use gross margin instead of revenue, subtract the cost of serving them, and add referral value only if you can show it. Keep every guess on the low side.

Why it matters

Without CLV, you guess how much to spend to win a customer. A carpet cleaner who sees $250 per job may think a $150 lead is too expensive. If the average customer books twice a year for four years and refers one neighbor, that same lead may be worth paying for. The opposite mistake hurts more: an inflated CLV makes bad ad spending look smart until the cash runs out.

21.9.2 Purchase frequency

What it means: how many times a typical customer buys from you in a year.

How to do it: pull every customer who bought in the last 12 months from your records or customer relationship management (CRM) system. Count their purchases and divide by the number of customers. For a new business, use what you’ve seen so far, not what you hope.

Common mistake: counting only your best repeat customers. Include the many who bought once and never came back.

21.9.3 Retention period

What it means: how long a typical customer keeps buying.

How to do it: look at customers who started at least a year or two ago. Note how many are still buying after 1, 2, and 3 years. If you don’t have that history yet, use a short period, such as 1 or 2 years, and update it as real data comes in (see 17.10 Retention and Reactivation).

Common mistake: assuming customers stay forever. A lawn care client may move, sell the house, or switch to a cheaper crew.

21.9.4 Gross margin

What it means: what’s left from each sale after the direct cost of doing the work, such as labor, materials, and supplies.

How to do it: multiply lifetime revenue by your gross margin percentage (see 21.1 Business Metrics and 7.1.8 Direct Delivery Cost). If a customer brings $2,000 over their lifetime and your margin is 40 percent, the margin value is $800.

Common mistake: using revenue. Revenue makes every customer look two or three times more valuable than they are.

21.9.5 Service cost

What it means: the costs of keeping a customer that aren’t in the job cost, such as support calls, reminders, refunds, payment fees, and account management time.

How to do it: estimate these per customer per year and subtract them. Pull refund and payment processing totals from your books. Estimate admin time in hours and multiply by what that time costs you.

Common mistake: leaving out refunds and redo visits. A pest control company with frequent free callbacks has a lower CLV than its invoices suggest.

21.9.6 Referral value

What it means: the extra profit you get when a customer sends you new customers.

How to do it: only count referrals you can trace, such as a referral field in your CRM or a referral code (see 18.7 Referral Programs and 15.8 Lead-Source Tracking). If 1 in 10 customers sends a paying referral, add one tenth of a new customer’s margin value. If you can’t trace referrals, leave this at zero.

Common mistake: assuming every happy customer refers someone. That guess can double your CLV on paper with nothing behind it.

21.9.7 Caution

What it means: CLV is an estimate built on guesses. Treat it as a range, not a fact.

How to do it: run three versions: low, expected, and high. Use the low one when you set your maximum spend to win a customer (see 7.8.13 Maximum Customer Acquisition Cost). Write down every assumption and the date you made it. Recheck the number every 6 to 12 months.

Common mistake: using the high version to justify an ad budget. If the low version doesn’t work, the plan doesn’t work.

A simple example

Hayden Window Washing charges $300 per visit. Customers book 2 times a year and stay about 3 years. That’s $1,800 in revenue. At a 45 percent gross margin, that’s $810. Reminders, fees, and the odd redo cost about $30 a year, so subtract $90. Referrals can’t be traced yet, so they count as zero. The conservative CLV is about $720.

When to get help from a pro

A certified public accountant (CPA) or bookkeeper can check that your margin and cost numbers match your books. Questions to ask:

Is the gross margin I’m using correct for how my books are set up?
Which costs am I missing from my service cost estimate?
Is my lifetime value reasonable to use in a loan application or business valuation?

Bill’s note

[Bill: add a short note. For example, how you think about what a SiteSmarty client is worth over time, or a business that overspent on ads because it counted revenue instead of margin.] If you’d rather have this done for you, SiteSmarty handles Google Business Profile management, which helps you keep the customers and reviews that make lifetime value grow.

How I did this for SiteSmarty

[Date I did this:]
[What I actually did, step by step: where I pulled purchase frequency, retention, and margin for SiteSmarty clients]
[What it cost and how long it took:]
[What surprised me or what I’d do differently:]
[Screenshot or photo to add, with private info blurred: the lifetime value sheet with low, expected, and high versions]
[Result so far:]

Questions people ask

What is customer lifetime value? The profit a typical customer brings you over the whole time they buy from you, after direct costs and service costs.

Should I use revenue or profit? Use gross margin. Revenue makes customers look more valuable than they are.

How do I estimate how long customers stay? Look at customers who started a year or more ago and see how many still buy. If you’re new, use 1 or 2 years until you have real data.

Should referrals count? Only when you can trace them to a specific customer. Otherwise count them as zero.

How often should I update it? Every 6 to 12 months, or after a big price or service change.

Audit check

Outline line	Question	Pass looks like	Fail looks like	Evidence to collect
21.9.2 Purchase frequency	Is yearly purchase frequency based on all customers?	Count from records for all customers	Based on top customers or a guess	CRM or sales report
21.9.3 Retention period	Is the retention period based on real history or a short, stated assumption?	Cohort counts or a dated short assumption	Customers assumed to stay forever	Retention sheet
21.9.4 Gross margin	Does CLV use margin instead of revenue?	Margin percent applied	Revenue only	CLV sheet and profit and loss report
21.9.5 Service cost	Are support, refunds, fees, and account costs subtracted?	Per-customer cost subtracted	No service costs	Books and fee reports
21.9.6 Referral value	Is referral value counted only when traceable?	Traced referrals or zero	Assumed referrals	CRM referral field
21.9.7 Caution	Is there a low, expected, and high version with dated assumptions?	Three versions, low one used for spending	One optimistic number	CLV sheet with dates

Where this fits

Do this first: 7.1.7 Average Sale, 21.7 Funnel Review

Do this next: 21.10 Conversion Rate Testing

Sources

Google Business Profile Help, "Tips to improve your local ranking on Google" (checked October 18, 2026)

This page explains general rules and Bill's own experience. It is not legal, tax, or insurance advice. Talk to a qualified professional about your situation.