When a company’s deductible expenses exceed its income, generally a net operating loss (NOL) occurs. If when filing your 2017 income tax return you found that your business had an NOL, there is an upside: tax benefits. But beware — the Tax Cuts and Jobs Act (TCJA) makes some significant changes to the tax treatment of NOLs. Pre-TCJA law Under pre-TCJA law, when a business incurs an NOL, the loss can be carried back up to two years, and then any remaining amount can be carried forward up to 20 years.