The U.S. IRS has issued a release reminding taxpayers that despite the tax return extension to 17 May 2021, the deadline for first quarter 2021 estimated tax payments remains 15 April 2021. --- IRS reminds taxpayers to make April 15 estimated tax payment IR-2021-78, April 8, 2021 WASHINGTON — The Internal Revenue Service today reminded self-employed individuals, retirees, investors, businesses, corporations, and others who pay their taxes quarterly that the payment for the first quarter of 2021 is due Thursday, April 15, 2021. The extension to May 17, 2021 for individuals to file their 2020 federal income taxes does not...