CAC

CAC (Customer Acquisition Cost) is the total cost of acquiring a new customer, calculated by dividing all sales and marketing expenses by the number of new customers acquired in that period. If you spent $100,000 on sales and marketing in January and acquired 200 new customers, your CAC is $500.

Why it matters: CAC is half of the most important equation in SaaS and subscription businesses: LTV:CAC. This ratio determines whether your business model is sustainable. The widely accepted benchmark is that LTV should be at least 3x CAC. Below 1x, you are losing money on every customer. At 1-3x, the business works but is fragile. Above 3x, you have a healthy model. Above 5x, you may be under-investing in growth and leaving market share on the table.

What to include in the calculation: fully loaded CAC includes all sales team salaries and commissions, all marketing spend (paid ads, content production, tools, events), marketing team salaries, sales and marketing software costs (CRM, email tools, ad platforms), and any other expense directly attributable to customer acquisition. Some companies also calculate "blended CAC" (all channels) and "paid CAC" (only paid marketing costs) to understand channel efficiency.

CAC payback period: beyond the LTV:CAC ratio, the payback period matters. This is the number of months it takes for a customer's cumulative gross profit to cover their CAC. If CAC is $600 and monthly gross profit per customer is $60, payback period is 10 months. For venture-funded startups, 12-18 month payback is acceptable. For bootstrapped companies, under 6 months is ideal. A short payback period means you recover your acquisition investment faster, which improves cash flow and reduces risk.

How to reduce CAC: invest in organic channels (SEO, content marketing) which have near-zero marginal cost. Build referral programs. Improve website and funnel conversion rates so more visitors become customers without additional spend. Focus on product-led growth (PLG) where the product itself drives acquisition through virality or self-serve. Shorten the sales cycle through better qualification and sales enablement.

Segmented CAC: always segment by channel and customer type. Your self-serve CAC might be $50 while your enterprise CAC is $5,000, and both could be healthy depending on the LTV of each segment. Blended CAC hides these important distinctions.

Common mistakes: not including salaries and overhead in the calculation (which makes CAC look artificially low). Comparing CAC across companies without accounting for different calculation methodologies. Not tracking CAC trends over time (a rising CAC is a red flag). Reducing CAC by cutting marketing spend that drives future pipeline, which improves the short-term number but harms long-term growth.

Practical example: a SaaS company calculates their fully loaded CAC at $1,800 with an LTV of $4,200 (2.3x ratio, below the 3x target). They analyze by channel: organic (CAC $320), paid search (CAC $1,400), paid social (CAC $2,600), and outbound sales (CAC $4,800). They reallocate 30% of paid social budget to SEO content investment and improve their outbound qualification criteria. Six months later, blended CAC drops to $1,200 and the LTV:CAC ratio improves to 3.5x.