6 Unit Economics Numbers Investors Check Before Your Next Raise
Sam's List Editorial | 2026-07-31
6 Unit Economics Numbers Investors Check Before Your Next Raise The growth chart gets you the meeting. The unit economics investors check decide whether they believe the growth chart repeats. The Six Unit Economics Investors Check Here are the six numbers that get checked: fully loaded customer acquisition cost, CAC payback period in months, contribution margin per customer, gross revenue retention, net revenue retention, and cohort behavior over time. A seventh, sales efficiency, is the sanity check on all of them. None of these are exotic. What surprises founders is that the diligence version of each number is almost always worse than the deck version, and the gap itself becomes the conversation. 1. Fully Loaded Customer Acquisition Cost Most founders compute CAC as ad spend divided by new customers. A diligence team computes it as everything you spent to acquire customers divided by the customers you acquired. Everything means paid media plus sales salaries and commissions, plus the marketing team's salaries, plus the tools that only exist to support acquisition, plus agency and contractor spend. If a cost would disappear when you stopped acquiring customers, it belongs in the numerator. The gap between the two versions is usually large. A company reporting 900 dollars of CAC on media alone can land near 2,400 fully loaded once two salespeople and a marketing manager are included. Neither number is a lie. Only one of them survives diligence. Compute it fully loaded, monthly, and keep the media-only figure alongside it as a channel metric. Being the person who volunteers the higher number is worth more than being caught with the lower one. 2. CAC Payback Period in Months This is the number that decides whether your growth is fundable or self-funding, and it is the one most often calculated wrong. The formula: fully loaded CAC divided by monthly gross profit per customer. Gross profit, not revenue. Using revenue in the denominator shortens the payback period by exactly the size of your cost of delivery, which is the part investors care about. A company with 2,400 in fully loaded CAC and 300 in monthly gross profit per customer has an 8-month payback. Change the denominator to 400 in monthly revenue and it looks like 6 months. The 8 is the real one. Payback matters because it tells you how long each new customer holds cash hostage. Shorter payback means growth funds itself sooner. Longer payback means growth requires capital, which is a legitimate reason to raise and a poor thing to discover during diligence. 3. Contribution Margin Per Customer...
