How to Calculate the True Cost of a Signed Case for Your PI Firm

Your Google Ads dashboard says you spent $180,000 last quarter. You signed 60 cases. So cost per case is $3,000, right? Not quite. That number ignores the intake team working those leads, the tech stack they rely on, and the overhead keeping the lights on. The real number is closer to $4,600 — and that gap determines whether a channel is profitable or quietly bleeding you dry.

This article walks through how to calculate the full cost of a signed case, component by component. It takes more effort than simple division — but it produces a number that actually tells you whether your marketing and intake operation is profitable.

Why “Marketing Spend Divided by Signed Cases” Falls Short

Simple division — total marketing spend ÷ signed cases — is a useful proxy, but it understates true cost in two important ways.

It ignores intake labor. Every lead requires staff time: contact attempts, qualification calls, follow-up sequences. That labor scales with lead volume, not signed case volume. A vendor that drives high lead volume but low conversion forces more intake work per signed case — and that cost never shows up in the marketing spend line.

It ignores the time lag.February's signed cases mostly started as leads in December and January. Dividing February spend by February signings mixes up two different cohorts. You need to match spend to the leads it produced, not the calendar month it landed in.

With that context, here's the full calculation.

The Complete Cost Per Case Formula

True cost per case = (Direct marketing spend + Intake labor cost + Overhead allocation) ÷ signed cases from the same lead cohort.

Three components. Let's walk through each.

Component 1: Direct Marketing Spend

The most straightforward component — every dollar spent generating leads in the period you're measuring:

• Paid search (Google Ads, Bing Ads)
• Local Service Ads
• Social media advertising
• Lead vendor invoices
• SEO and content agency retainers (if primarily lead-gen focused)
• Billboard, TV, radio (if you can attribute leads to these)
• Referral marketing costs

Leave brand marketing spend out unless specific leads can be tied to it. Brand campaigns build long-term reputation — blending them into cost per case distorts the signal.

Example: $180,000 total direct marketing spend for a 90-day cohort.

Component 2: Intake Labor Cost

Your intake team is a direct cost of case acquisition. No intake team, no signed cases. Include three elements:

• Fully-loaded staff cost: Base salary plus benefits, payroll taxes, and variable compensation. Four intake specialists at $55,000 base with a 30% burden rate runs about $71,500 each — $285,000/year, or $23,750/month.
• Management allocation: If you have a Director of Intake or a supervisor primarily focused on intake, include the percentage of their time dedicated to managing the function.
• Intake technology: Phone system, call tracking, CRM seats for intake staff. Include here if not already in your marketing spend line.

Example: 4 specialists at $23,750/mo + $3,000 in intake tech = $26,750/month, or $80,250 for the 90-day period.

Component 3: Overhead Allocation (Optional, But Honest)

Some firms include a share of general overhead — office space, admin staff time, and management. This is the most debated component; many firms leave it out to stay comparable to industry benchmarks.

If you include it, be consistent. Use the same methodology every period so the numbers stay comparable over time. A clean approach: allocate overhead proportionally to headcount. If intake staff are 15% of total firm headcount, assign 15% of firm overhead to intake.

Example: 15% of $40,000/mo firm overhead = $6,000/mo, or $18,000 for the 90-day period.

Putting It Together

Roll up the three components for the same 90-day period:

• Direct marketing spend: $180,000
• Intake labor: $80,250
• Overhead allocation: $18,000
• Total cost: $278,250

Divide by 60 cases signed from that cohort:

True cost per signed case: $4,638

The simple calculation — $180,000 ÷ 60 — gives you $3,000. That's a 55% undercount. When you're deciding whether to double a vendor's budget or cut it, the difference between $3,000 and $4,638 per case is the difference between a good decision and a bad one.

How to Handle the Time Lag

The most accurate approach is cohort-based tracking: instead of comparing spend and signings in the same calendar month, track leads that arrived in a specific window — say, October 1–31 — and count how many signed by a closing date 90 days out.

This requires your CRM to record both lead arrival date and signing date, with filtering by cohort. More setup upfront, but the numbers are actually meaningful because you're matching the right spend to the right outcomes.

If cohort tracking isn't possible yet, use a lagged comparison: divide current-month marketing spend by signed cases from 6–8 weeks prior. It approximates the cohort method by accounting for the typical lead-to-signing window.

Calculating Cost Per Case by Vendor

Firm-level cost per case tells you about overall acquisition economics. The real decisions — cut this vendor, double that one — require the same calculation at the vendor or channel level.

To break it down by vendor, attribute three things:

• Marketing spend:Each vendor's invoices for the period. Straightforward.
• Intake labor:Estimate the share of intake time spent working each vendor's leads. Lead volume share is a clean proxy — if Vendor A sends 30% of your leads, allocate 30% of intake labor cost to Vendor A.
• Signed cases: Requires source tagging in your CRM. Every signed case must link back to the lead source that produced it.

Run this calculation and you'll find cost per case variation across vendors that marketing spend alone would never surface.

What to Do With the Number

Once you have a true cost per case — by vendor and in total — benchmark it against your expected fee per case type. On a motor vehicle case with a $10,000 contingency fee, a $4,638 cost per case means marketing and intake alone consume 46% of the fee — before case costs and attorney time enter the picture.

Whether that's sustainable depends on your fee structure, overhead, and growth goals. What matters is that you know the number and can track how it moves as you adjust vendors, channels, and intake processes.

Firms that track true cost per case quarterly consistently find ways to improve it — because they can see what's driving it up or down. That visibility is impossible without the full calculation.

A Simple Starting Framework

Never run this calculation before? Here's the fastest way to get a directional number:

1. Pull your last 90 days of marketing spend, broken out by vendor or channel.
2. Calculate your intake team's fully-loaded monthly cost and multiply by three.
3. Pull every case signed in that same 90-day window, with lead source tags attached.
4. Divide (marketing spend + intake cost) by signed cases — total first, then by source.
5. Compare the result against your average expected fee per case type.

The first run won't be perfect. Source tagging is often inconsistent, and the time lag means some cases signed in the window came from leads before it. But you'll get a meaningful directional picture — and it will be far more useful than marketing spend alone.