Ad platforms make it easy to celebrate the wrong numbers. Impressions, clicks and click-through rate all go up and to the right, while the bank balance tells a different story.
The number that matters
Cost per customer is simple: what you spent on a channel, divided by the paying customers it produced. It is harder to measure than cost per click, which is exactly why it is worth the effort.
How to get there
- Track past the form. Connect calls and forms to your CRM so you can see which leads became customers.
- Feed results back to the platform. Tell Google and Meta which leads converted, so their bidding learns what a good lead looks like.
- Judge keywords and audiences on customers. A search term with expensive clicks can still be your cheapest source of customers.
Optimise for the result you can bank, not the one the dashboard shows first.
A simple weekly check
For each channel, write down spend, leads, customers and cost per customer. Move budget toward the lowest cost per customer, test something new with a small share, and repeat next week.