Understand new customer CAC for ecommerce
By Drizzle team
1 min read
Customer acquisition cost should count new customers and the costs used to win them.
Set the boundary
Choose a period, add media spend and relevant acquisition production or agency costs, then divide by first-time customers from that period.
Avoid a mixed denominator
Returning buyers may lower platform purchase CPA while adding no new customers. Keep them out of new-customer CAC and note tracking gaps.
Use a working estimate
Try the CAC calculator and compare the result with first-order contribution. Treat later orders separately until you have repeat-purchase evidence.
A worked example
Suppose a month brings 30 first-time buyers, $1,200 in media spend, and $300 in creator fees. The simple blended CAC is $50. If a platform also reports 20 returning-customer orders, do not put those 20 in the new-customer denominator. Compare $50 with the contribution from a first purchase before deciding whether the acquisition rate works.
Decision check
Keep the numerator, denominator, date range, currency, and attribution definition with every reported result. A metric describes one part of the shopper path; compare it with visits, purchases, and order contribution before changing the creative or budget. State what the observation cannot establish.