As a business owner there are a few key dates to remember for tax preparation and planning. Review these important dates for individual tax return preparation:  April 15 – Individual tax return (form 1040) April 15 – 1st quarter estimated taxes April 15 – Last day to make HSA and IRA contributions June 15 – 2nd quarter estimated taxes September 15 – 3rd quarter estimated taxes October 15 – Final due date for extended returns January 15, 2021 – 4th quarter estimated taxes