(CNN) - Next Monday, May 17, is the official deadline for individuals to file their 2020 federal tax return, and in most instances their state tax return, too. It's a month later than usual, thanks to the pandemic. But the filing deadline's not the only thing that's changed. Many of the upheavals over the past year have caused other changes to your taxes. Due to the COVID crisis, there are plenty of new and revised provisions and important dates you will need to know about before filing your return this year. Here are some of the most important ones. Why May 17? While the original filing and payment due date was April 15, the IRS has pushed the deadline to May 17 to give individual filers, tax preparers and the IRS itself more time to sort through the many changes affecting one's 2020 taxes from the latest Covid relief package. As it is, the filing season started a few weeks late this year since the IRS had its hands full administering provisions, like stimulus checks