The
Cost field in the Campaign Performance Report will get you the amount spent on your campaigns. However, the data retrieved in the said field is not real time as there are delays on the updates of the reporting metrics. You could refer to our
data freshness guide for more details. For getting reports on a campaign level, you may check the
Campaign Performance Report guide for more details. Also, reports are the only way to retrieve metrics such as
Cost in the AdWords API.
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