Unit Economics for Retail & CPG: CAC, LTV, and Contribution Margin
If you don't know what it costs to acquire a customer — or what they're worth — you're flying blind.
Unit economics is the financial foundation of any scalable retail or CPG business, yet many operators manage by revenue and gross margin alone without examining the metrics that determine whether growth is actually profitable. Customer acquisition cost (CAC), lifetime value (LTV), and contribution margin are the three numbers that collectively answer a question every business owner needs to be able to answer: for every customer we bring in, do we make money — and how much?
Customer acquisition cost is calculated by dividing total sales and marketing spend by the number of new customers acquired in a given period. For a DTC brand spending $200,000 annually on paid media and acquiring 4,000 new customers, the CAC is $50. That number is only meaningful, however, when compared to what those customers are worth over time. Lifetime value — calculated as average order value multiplied by purchase frequency multiplied by average customer lifespan — provides that comparison. A customer who buys twice a year at $80 per order and stays for three years generates $480 in lifetime revenue.
Chart: CAC vs. LTV ratio by business model — DTC subscription, DTC transactional, wholesale, and omnichannel.
Contribution margin — revenue minus variable costs directly tied to that unit of sale — bridges CAC and LTV into a single profitability picture. For a CPG brand selling a $40 product with $14 in COGS, $4 in fulfillment, and $2 in payment processing, the contribution margin is $20 per unit, or 50%. That 50% must cover CAC, overhead, and generate profit. If CAC is $50 and the average customer buys once, the business loses money. If the same customer buys three times over two years, the math works.
Finance leaders should track unit economics at the channel level, not just in aggregate. A brand that looks healthy overall may be running a structurally unprofitable DTC channel that is being subsidized by wholesale margins. Channel-level contribution analysis frequently reveals that growth in a particular segment is consuming cash rather than generating it — a dynamic that accelerates as the business scales.
Bottom Line: Unit economics are not a startup metric — they are the lens through which every profitable retail and CPG business should evaluate growth decisions.