What a New Client Really Costs You: Marketing CAC for Med Spas

Marketing spend is easy to measure. What it buys is harder. Client acquisition cost, often called CAC, connects the two.

The basic calculation

CAC = marketing spend for a period ÷ new clients acquired in that period

If you spent $6,000 last month and gained 40 new clients, CAC is $150.

Include the full cost

Count ad spend, agency or freelancer fees, promotional discounts given to new clients, referral rewards and the cost of any free consultations or introductory offers.

Measure by channel

Ask every new client how they found you and record it in your POS or booking system. Then calculate CAC by channel: paid social, search, referrals, influencer partnerships, events and so on. Channels often differ widely.

Compare with what a client is worth

CAC alone does not tell you whether marketing is working. Compare it with client lifetime value: the contribution margin a typical client generates over the time they stay. A higher CAC is fine for channels that bring clients who stay and spend more.

Watch first-visit profitability

Introductory offers can make the first visit unprofitable. That is acceptable if enough of those clients return at full price. Track the share of new clients who rebook within 90 days, by channel.

Common pitfalls

• Counting returning clients as new because they used a new-client promotion
• Ignoring the cost of discounts given to new clients
• Judging a channel after one month, before rebooking data exists
• Not recording the source for every new client

A monthly marketing review

For each channel: spend, new clients, CAC, 90-day rebooking rate and estimated lifetime contribution. Move budget gradually toward channels where clients cost less relative to what they are worth.