The Tax Cuts and Jobs Act of 2017, eliminated the old NOL rules of 2-year carrybacks, carryforward 20 years. Instead, it disallowed NOL carrybacks for all post-2017 losses and extended the 20 year carryforward to an unlimited carryforward (limiting the offset to 80% of taxable income). Now, under the CARES Act, NOLs from 2018, 2019, and 2020 can be carried back up to 5 years; and such losses may offset 100% of taxable income rather than 80%. Taxpayers may also waive their NOLs in a particular year by submitting the proper (and very specific) documentation. See Rev Proc 2020-24 and IRS Notice 2020-26 for more guidance.