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

Most PI firms know roughly what they spend on lead generation. Far fewer know their true cost to acquire a signed case — the number that accounts for marketing spend, intake labor, overhead allocation, and the time value of the process from first contact to signature.

This article walks through how to calculate the full cost of a signed case, step by step. The calculation is more involved than dividing marketing spend by signed cases — but the result is a number that actually tells you whether your marketing and intake operation is profitable.

Why “Marketing Spend Divided by Signed Cases” Is Incomplete

The most common version of cost per case is simple division: take your total monthly marketing spend, divide by signed cases that month, and call that your cost per case. This number is useful as a quick proxy, but it understates the true cost in two important ways.

First, it ignores intake labor. Every lead that enters your funnel requires staff time to work — initial contact attempts, qualification calls, follow-up sequences. That labor has a cost, and it scales with lead volume, not just signed case volume.

Second, it ignores the time lag problem. If you divide February marketing spend by February signed cases, you're dividing spend against cases that largely came from December and January leads. The cases signed in February started as leads weeks or months ago. Matching spend to the right period requires cohort tracking, not monthly averages.

With that context, here's the full calculation.

The Full Cost Per Case Formula

True cost per case = Direct marketing spend + Intake labor cost + Overhead allocation, all divided by signed cases from the same lead cohort.

Let's break down each component.

Component 1: Direct Marketing Spend

This is the most straightforward component. Include every dollar spent on lead generation for 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-generation focused)
• Billboard, TV, radio (if you track leads attributable to these)
• Referral marketing costs

Do not include brand marketing spend unless you can attribute specific leads to it. Brand campaigns are an investment in long-term reputation; mixing them into cost per case calculations dilutes 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. Without them, leads don't become signed cases. The calculation:

• Intake staff fully-loaded cost:Base salary plus benefits, taxes, and any variable compensation. If you have four intake specialists at $55,000 base plus 30% for benefits and taxes, that's approximately $71,500 each, or $285,000 annually — about $23,750 per month.
• Intake management allocation: If you have a director of intake or a supervisor whose time is primarily intake- focused, include a portion of their compensation. A rough allocation is whatever percentage of their time is dedicated to intake management.
• Intake technology costs:Phone system, call tracking software, CRM seats for intake staff. Include these here if they aren't already in your marketing spend.

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

Component 3: Overhead Allocation (Optional, But Honest)

For a complete picture, some firms include a portion of general overhead — office space used by the intake team, a share of administrative staff time, and management overhead. This is the most contested component, and many firms exclude it from cost per case calculations to maintain comparability with industry benchmarks.

If you include overhead, be consistent. Use the same allocation methodology every period so your cost per case numbers are comparable over time.

A reasonable approach: allocate overhead proportionally to headcount. If intake staff represent 15% of total firm headcount, allocate 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

Using the examples above:

• Direct marketing spend (90 days): $180,000
• Intake labor (90 days): $80,250
• Overhead allocation (90 days): $18,000
• Total cost (90 days): $278,250

If your intake team signed 60 cases from leads that arrived in that 90-day window:

True cost per signed case: $4,638

Compare that to the simpler calculation: $180,000 ÷ 60 cases = $3,000. The “simple” number understated the true cost by 55%. That gap matters when evaluating whether a channel is actually profitable.

How to Handle the Time Lag Correctly

The most technically accurate approach to cost per case is cohort-based tracking: instead of comparing spend and signings in the same calendar period, track leads that arrived in a specific window (say, October 1– October 31) and calculate how many of those leads became signed cases by a closing date (say, 90 days later, December 31).

This requires your CRM or case management system to record both the lead arrival date and the signing date — and to support filtering by lead cohort. It's more work to set up, but it produces far more accurate numbers because you're matching the right spend to the right outcomes.

If cohort tracking isn't possible right now, a practical workaround is to use a lagged comparison: divide current-month marketing spend by signed cases from 6–8 weeks ago. This approximates the cohort approach by accounting for the typical lead-to-signing time.

Calculating Cost Per Case by Vendor

The firm-level cost per case is useful for understanding your overall acquisition economics. But the real decision-making power comes from calculating cost per case at the vendor or channel level.

To do this by vendor, attribute:

• Marketing spend:Straightforward — each vendor's invoices for the period.
• Intake labor:Estimate the portion of intake time spent working each vendor's leads. A reasonable proxy is lead volume share — if Vendor A provides 30% of your leads, allocate 30% of intake labor cost to Vendor A.
• Signed cases: Requires source tagging in your CRM. Each signed case needs to be linked to the lead source that produced it.

This calculation will reveal cost per case variation across vendors that the simple marketing-spend-only number obscures.

What to Do With the Number

Once you have a true cost per case — by vendor and in total — compare it against your expected fee per case type. For a motor vehicle case where the expected contingency fee is $10,000, a $4,638 cost per case means your marketing and intake operation is consuming roughly 46% of the fee before you account for case costs and attorney time.

Whether that number is sustainable depends on your fee structure, overhead, and growth goals. The important thing is that you know it — and that you can track how it changes as you adjust vendors, channels, and intake processes.

Firms that track true cost per case quarterly tend to find consistent improvement over time because they have the visibility to identify what's driving cost up or down. That improvement is hard to find — and impossible to prove — without the calculation.

A Simple Starting Framework

If you've never calculated your true cost per case before, here's a practical starting point:

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

This won't be perfect the first time — source tagging may be inconsistent, and the time lag means some cases in the window came from leads outside the window. But it will give you a meaningful directional picture that's far more useful than marketing spend alone.