Events Calendar The interactive calendar highlights federal and state tax due dates, special firm events and other important dates that may be of interest to you. The calendar is updated regularly, so check back often to keep track of filing requirements, deadlines, and other events that will help you stay current and up-to-date. The calendar below shows important tax due dates and other events. Events have been categorized as Individual, Business and State tax due dates, as well as general Firm events. Hover over an event to view its details.