The Tax Cuts and Jobs Act of 2017 included a provision that impacted net operating losses. 

Per the language in the TCJA, a non-corporate taxpayers’ business loss deductions are limited to a threshold amount (IRC Sec. 461(I) as modified by TCJA Sec. 11012(a)). When there is a non-deductible excess business loss, this amount is carried forward and treated like a net operating loss carryover to the next tax year. See Chapter 3.25 for more about this limitation.

However, the CARES Act (Sec 2304) made the loss limitation inoperable for businesses (including farming) through 2020. Since this change is retroactive to 2018, taxpayers who were affected by the limitation can amend their 2018 returns. This also applies to 2019 and 2020, so if a 2019 or/and 2020 return has already been filed, it can also be amended. Further, the non-deductible excess business loss from years 2018, 2019, or 2020 would no longer be carried forward as an NOL carryover.