Money Did your state extend the deadline for income tax returns like the IRS? Here’s when 2020 taxes are due. May 16, 2021 Jayme Deerwester, USA TODAY Comments Off on Did your state extend the deadline for income tax returns like the IRS? Here’s when 2020 taxes are due. The IRS will not extend the tax deadline again in 2021. Most federal and state income tax returns are due Monday, May 17 unless you file an extension.