Cost per action (also known as CPA, pay per action, PPA, or cost per conversion CPC) is a pricing model in digital advertising when advertisers pay for the specific action. Such actions include clicks, filling out the form, buying, installing, etc. The action depends on what is relevant for the advertiser’s industry or campaign goals. Sometimes the action is specified by ad networks.
In the case of the pay per impression model, marketers paid for views that do not result in sales most of the time. The CPA pricing model allows advertisers to pay for feasible results, actual value. There is no cost risk involved. Consequently, they feel more comfortable and secure about digital advertising and are more willing to pay. It is needless to say that pay rates for action are higher.
However, this option is not preferred by publishers. It takes more effort to call users to action rather than simply putting a banner up. Therefore, only a few ad networks have the CPA pricing model.
Desired by marketers and unwanted by publishers, this option has become a disputable one. The one niche where it does work well is affiliate marketing.