An apparatus, system, and method are disclosed for retaining email response time trends. A send module determines a send time, the time that a user sends an email message to a recipient. A receive module determines a receive time, the time that the user receives a response from the recipient. A response time module determines a response time that corresponds to the email message based on an elapsed time between the send time and the receive time. A content identifier module determines a content identifier for the email message. A trend module determines a response time trend that corresponds to the recipient and the content identifier based on the response time and on a plurality of previous response times of the recipient. The plurality of previous response times correspond to a plurality of previous email messages between the user and the recipient that match the content identifier.