In todays post I want to talk about why your CAC calculation is probably WRONG and show you how to fix it with a short example in Excel.
In this video, I draw on my two decades of experience as a startup CFO to explain why the standard Customer Acquisition Cost (CAC) formula—total sales and marketing spend divided by new customers—fails to work in most B2B settings.
I’ll show you how to move beyond a theoretical value and get to a meaningful number that reflects the real world.
What you’ll learn in this video:
• Segmentation: Why calculating one average CAC for a 2-week SME lead time and a 9-month Enterprise cycle is meaningless.
• Allocating Costs: How to use ratios (like time spent or revenue proportions) to split salaries and marketing spend between segments.
• “Fully Loaded” Costs: Why you must include overhead, travel, and even “general branding” spend in your formula, despite what your marketing team might tell you.
• Handling the Sales Cycle: How to lag and pro-rate your costs (e.g., using a 6-month rolling window for Enterprise) to align spend with outcomes.
• The Commission Exception: Why sales commissions should always be directly attributed.
EXCEL DEMONSTRATION: In the second half of the video I jump into Excel to show exactly how to set up these formulas, apply the ratios, and calculate a realistic, segmented CAC that you can actually use to scale your business.
#CAC #StartupFinance #CustomerAcquisitionCost #SaaS #B2BMarketing #CFO #FounderTips #ExcelTutorial #BusinessMetrics
