Under the current tax system, quarterly estimated tax payment due dates fall on 4/15, 6/15, 9/15, and 1/15; which don’t quite match up with the actual quarter end dates throughout the year. Proposed legislation recently introduced as part of a bill in Congress seeks to establish more uniformity for the periodic payment dates – changing each quarterly estimated tax payment due date to the 15th date after the end of a calendar quarter: 4/15, 7/15, 10/15, 1/15. Making the change to a true quarter end date, would help many taxpayers to more accurately calculate and time their quarterly tax payments.