A net operating loss (NOL) is when business losses exceed income.
Prior toJanuary 1, 2018, NOLs were able to offset 100% of taxable income. They were allowed to be carried back two years and carried forward for twenty years. You could affirmatively elect with a timely filed return to NOT carryback (the default) and instead carry forward only (permanent, could not change it for that year).
Under the new law effective in 2018, an NOL can offset only 80% of taxable income in any given tax year. NOLs can be carried forward only. The 20-year carryforward period is changed to an indefinite carryforward period NOLs created in tax years beginning before January 1, 2018 are subject to the old rules. Only NOLs generated in tax years beginning after December 31, 2017 are subject to the new rules.