Taxpayers can look up federal tax refund due dates by going to the Publication 509 section of the Internal Revenue Service website. The General Tax Calendar has the due dates that most taxpayers need, such as the due dates for Form 1040 and 1040-ES, notes the IRS.
Publication 509 also includes the due dates for the forms required of partnerships, such as Form 1065, and corporations, such as Form 1120, as stated by the IRS. It contains an Employer's Tax Calendar and an Excise Tax Calendar. The publication also defines the quarters of the year and provides information about fiscal-year taxpayers and extended due dates. It discusses due date adjustments that apply when a due date falls on a Saturday, Sunday or legal holiday. The IRS website takes users directly to the source of the due dates, providing them with the most up-to-date information.