What is cost per acquisition (cpa) campaign and how to run it?

CPA is just one of four ways that you can pay for your bids. It's the most recent one but here are all four explained.

Manual Bidding:

This is the normal bidding style that people use. It's the default setting when you start a campaign and it's basically telling Google the maximum you are prepared to pay for a click.

Preferred Cost Bidding:

In this case you set an average price you are prepared to pay for your clicks and Google manages your account for you to even out the amount you pay for clicks so that you are charged this average amount over time.

Budget Optimizer:

Here you don't set a bid price at all. You simply set a 30 day budget for your campaign and Google will manage the bid prices for you within that budget. You cannot use this for content bidding campaigns and if you have any content bids mixed into your search network campaigns (shame on you!) they will be turned off if you select this bidding option.

Conversion Optimiser:

This is their latest bidding option and the one we have been discussing above. It's also called cost per acquisition bids. With this option, you set a price that you are willing to pay for a conversion and Google will manage your click bidding in order to deliver conversions at that price.

Clearly for this option you will need to have conversion tracking on your campaign. Another limitation is that your campaign must have over 200 conversions in the last 30 days. This is because Google uses conversion history to determine the bid prices it will set on your behalf to get conversions at your requested price.

To set any of these options you go to the Campaign Settings and look under the section Advanced Options. The first option is Keyword Bidding. Just click on the View and Edit options link and you can select one of the four bidding options for your campaign.

Cheers