A system and method for filtering detected anomalies in cloud service usage activities associated with an enterprise uses a trusted location analysis to filter detected anomalies. The locations from which the cloud usage activities are made are analyzed and designated as trusted or non-trusted. The trusted location determination is used to filter the detected anomalies that are associated with trusted locations and therefore may be of low risk. In this manner, actions can be taken only on detected anomalies that are associated with non-trusted locations and therefore may be high risk. The system and method of the present invention enable security incidents, anomalies and threats from cloud activity to be detected, filtered and annotated based on the location heuristics. The trusted location analysis identifies trusted locations automatically using cloud activity usage data and does not rely on potentially unreliable location data from user input.