In this advertising context, average cost per action, or CPA, divides conversion cost by the number of recorded conversions. Google Ads distinguishes the actual average CPA from a target CPA used for bidding. The action being counted must be stated for the figure to be meaningful. Source: Google Ads: Average cost per action definition

Name the action beside the cost

Suppose a worked example spends £300 and records 15 completed enquiry forms. The CPA for that action is £20. Label it “cost per completed enquiry”, then decide how the sales team will assess those enquiries. This keeps the report from implying that every counted action was a booking.

Compare like with like

Keep the conversion definition and reporting period consistent when comparing campaigns. Show a change from form submissions to confirmed bookings as a change in measurement, with a clear date. Otherwise, the team could treat two differently defined figures as evidence of an improvement or decline.

Written and updated by Travelgenix. Sources checked on 16 October 2026. Worked examples and recommendations are editorial illustrations, not customer results.