Example methods and apparatus to determine impressions using distributed demographic information are disclosed. A disclosed example method to monitor media exposure involves receiving, at a first internet domain, a first request from a client computer, the first request indicative of access to the media at the client computer. The example method also involves determining if the client computer is known. If the client computer is not known, a response is sent from the first internet domain to the client computer, the response to instruct the client computer to send a second request to a second internet domain, the second request to be indicative of access to the media at the client computer. If the client computer is known, an impression of the media is logged.