How to Calculate Your Cost Per Acquired Client (A Simple Formula)

Cost per acquired client (sometimes called customer acquisition cost, or CAC) is total spend on a channel divided by the clients it signs. It's the single most useful number a solo or small criminal defense firm can track, and also one of the least commonly tracked. Getting the inputs right is where most firms fall short.

The formula

Total spend on a channel ÷ number of clients signed from that channel = cost per acquired client.

If you spent $2,000 on referrals last quarter and signed 5 clients from them, your cost per client from that channel is $400. That's the whole calculation — the work is in tracking the inputs accurately.

What should you include in total spend?

The per-lead or per-referral price is the obvious input. The ones people forget:

• Any monthly platform or subscription fee
• Staff time spent on intake calls specific to that source
• Mail/print costs if the source includes physical outreach
• Your own time, if you're the one following up

Leaving out staff and personal time understates your real cost — it just moves the cost from a line item to your calendar, where it's harder to see but no less real. How much a criminal defense lead costs explains why the sticker price differs so much by pricing model.

What counts as a client signed from a channel?

This is where tracking discipline matters most. Every new client needs a source tag at intake — not a guess made three months later trying to remember where they came from. If two channels both touched the same prospect before they signed, decide on a consistent rule up front (first touch, last touch, or split credit) and use it consistently rather than case by case. How to track a lead from referral to signed client walks through the tagging habit.

Why is this number more useful than lead count?

Lead count feels productive but doesn't tell you anything about return. Fifty leads that produce two clients at $3,000 in spend is a worse outcome than fifteen leads that produce three clients at $1,200 in spend — the lead count alone would suggest the opposite. How many leads it takes to land one client shows how the lead-to-client ratio connects the two numbers.

How do you use the number once you have it?

Cost per acquired client is only useful in comparison — against your average case value (is this client worth more than they cost to acquire?), against other channels (which one actually performs best?), and against itself over time (is this number improving or drifting?). Track it quarterly at minimum; monthly if your volume supports it. How much a criminal defense case is worth helps with the case-value side, and how much you should spend to acquire a client turns the comparison into a budget ceiling.

See current per-referral pricing to plug into your own calculation.