NOL Overview: Post-TCJA Rules
The Tax Cuts and Jobs Act of 2017 (TCJA) significantly changed the net operating loss (NOL) rules. For NOLs arising in tax years beginning after December 31, 2017: (1) the NOL deduction is limited to 80% of taxable income (before the NOL deduction); (2) NOLs can be carried forward indefinitely (no 20-year limit); and (3) the 2-year carryback is eliminated (except for farming NOLs, which retain a 2-year carryback). The CARES Act temporarily suspended the 80% limitation for 2018–2020 NOLs and allowed a 5-year carryback for those years; the suspension has expired and the 80% limitation applies again for NOLs arising in 2021 and later.
The NOL deduction is a powerful planning tool for businesses with volatile income. A business that has a $500,000 NOL in Year 1 can carry the NOL forward to offset up to $400,000 (80% of $500,000) of taxable income in Year 2, saving approximately $132,000 in federal tax at the 33% marginal rate. The remaining $100,000 of NOL carries forward to Year 3 and beyond.
NOL Calculation
The NOL is the excess of deductions over gross income, with certain modifications. The following items are excluded from the NOL calculation: (1) the NOL deduction itself; (2) the §199A QBI deduction; (3) capital losses in excess of capital gains; (4) the §1202 QSBS exclusion; and (5) certain other items. The modified taxable income (before NOL deduction) is the base for the 80% limitation.
| Year | Taxable Income (before NOL) | 80% Limitation | NOL Deduction | Taxable Income (after NOL) | NOL Carryforward |
|---|
| Year 1 | ($500,000) loss | N/A | N/A | ($500,000) | $500,000 |
| Year 2 | $600,000 | $480,000 | $480,000 | $120,000 | $20,000 |
| Year 3 | $400,000 | $320,000 | $20,000 | $380,000 | $0 |
Farming NOL Carryback
Farming NOLs retain the 2-year carryback under §172(b)(1)(B). A farmer with a $200,000 NOL in 2026 can carry the NOL back to 2024 and 2025, generating an immediate refund of taxes paid in those years. The carryback is limited to the farming NOL — non-farming losses cannot be carried back. Farmers can elect to waive the carryback and carry the NOL forward instead.
Section 382 Limitation on NOL Carryforwards
When a corporation undergoes an ownership change (more than 50% change in ownership over a 3-year period), the annual NOL deduction is limited under §382 to the value of the corporation at the time of the ownership change multiplied by the long-term tax-exempt rate. This limitation is critical for startup companies that raise venture capital — each financing round may trigger an ownership change and limit the use of pre-change NOLs.
Practitioners should review the §382 limitation for corporate clients with significant NOL carryforwards before any ownership change transaction (merger, acquisition, financing round). The §382 limitation can significantly reduce the value of NOL carryforwards in M&A transactions.
More Tax Planning FAQs
What is the IRS audit risk for this strategy?
The IRS audit rate for individual returns is approximately 0.4% overall, but increases significantly for returns with
Schedule C income, large deductions, or specific strategies. Proper documentation is the best defense against an audit. Keep contemporaneous records, maintain written agreements, and ensure all deductions are supported by receipts and business purpose documentation.
How does this strategy interact with the alternative minimum tax (AMT)?
Many tax strategies that reduce regular income tax can trigger or increase AMT liability. Common AMT triggers include: ISO exercises, large state tax deductions, accelerated depreciation, and passive activity losses. Taxpayers should model both regular tax and AMT before implementing aggressive tax strategies to ensure the net benefit is positive.
What is the statute of limitations for IRS assessment of this strategy?
The IRS generally has three years from the later of the return due date or filing date to assess additional tax. If the taxpayer omits more than 25% of gross income, the statute is extended to six years. There is no statute of limitations for fraudulent returns or failure to file. Taxpayers should retain tax records for at least seven years to cover the extended statute of limitations.
How should this strategy be documented to withstand IRS scrutiny?
Documentation is the cornerstone of any tax strategy. Maintain contemporaneous records (created at the time of the transaction), written agreements, business purpose statements, and receipts. For strategies involving related parties, ensure all transactions are at arm’s length and documented with fair market value support. The burden of proof is on the taxpayer to substantiate deductions.
What is the economic substance doctrine and how does it apply?
The economic substance doctrine (§7701(o)) requires that transactions have both objective economic substance (a reasonable possibility of profit) and subjective business purpose (a non-tax reason for the transaction). Transactions that lack economic substance are disregarded for tax purposes, and the 40% strict liability penalty applies. Legitimate tax planning strategies must have genuine business purposes beyond tax reduction.
How does this strategy affect state income taxes?
Federal tax strategies do not always produce the same results at the state level. Some states do not conform to federal tax law changes (e.g., bonus depreciation, QSBS exclusion). Taxpayers should model the state tax impact of any federal tax strategy, especially in high-tax states like California, New York, and New Jersey. Some strategies may save federal taxes while increasing state taxes.
What is the step-transaction doctrine and how does it apply?
The step-transaction doctrine allows the IRS to collapse a series of related transactions into a single transaction if the intermediate steps have no independent significance. This doctrine is used to prevent taxpayers from using artificial multi-step transactions to achieve tax results that would not be available in a single transaction. Legitimate tax planning strategies should have independent business purposes for each step.
How does this strategy interact with the passive activity loss rules?
Passive activity losses (§469) can only offset passive income. Active business income, wages, and portfolio income are not passive. Real estate rental income is generally passive unless the taxpayer qualifies as a Real Estate Professional. Passive losses that cannot be used currently are suspended and carried forward to offset future passive income or recognized when the passive activity is disposed of in a fully taxable transaction.
How do I set up an effective NOL carryback or carryforward election under §172 for my client?
To set up an NOL carryback or carryforward election under §172, first identify the tax years in which the NOL originated and the years to which the loss is to be applied. For 2026, the default treatment allows indefinite carryforwards, but a carryback is generally disallowed except for specific farming or insurance company losses. The taxpayer must file an amended return or a Form 1045 within the prescribed time frames to elect the carryback. Properly documenting the NOL calculation, including adjustments per §172(c), ensures accurate application. It is crucial to monitor IRS guidance as elections and carryback periods can vary by tax year and taxpayer type.
What steps should I take to accurately calculate and report a net operating loss for a partnership or S corporation client?
For partnerships and S corporations, NOLs are computed at the entity level per §702 and §1366, respectively, but the losses flow through to partners or shareholders. As a tax professional, ensure proper allocation of losses consistent with the partnership agreement or shareholder ownership percentages. The entity must complete all required schedules, including
Schedule K-1, reflecting each owner's share of income, deductions, and NOLs. Clients must then apply their distributive shares on their individual returns, respecting the limitations under §469 for passive losses. Coordination between entity and individual filings is essential to avoid double counting or missed deductions.
When must a client file for an NOL carryback refund claim, and what are the implications of missing the deadline?
For NOL carrybacks allowed under §172(b)(1), typically a claim for refund must be filed within two years from the end of the taxable year in which the loss arose. Clients must file Form 1045 or an amended return (
Form 1040X) to claim a refund. Missing this deadline results in the loss of the opportunity to carry back the NOL and receive an immediate refund, pushing the client to rely solely on carryforwards that offset future taxable income. It is critical to track these deadlines closely and consider extensions or waivers if applicable.
What documentation should be maintained to support a client's NOL position in case of an IRS audit?
Maintain comprehensive documentation including detailed income statements, expense ledgers, and reconciliation of book versus tax income to substantiate the NOL amount. Retain workpapers showing the step-by-step calculation of the NOL under §172, including adjustments required by IRC rules or temporary provisions. Evidence of carryback or carryforward elections, amended returns, and correspondence with the IRS should also be preserved. Documentation demonstrating the economic substance of loss-generating transactions can mitigate challenges under doctrines like the economic substance rule or §6662 accuracy-related penalties.
How do the passive activity loss rules under §469 interact with NOL calculations for rental real estate investors?
Per §469(c)(7), rental real estate activities may qualify as nonpassive if the taxpayer actively participates, allowing losses to offset nonpassive income. However, if losses are disallowed and suspended due to passive activity limits, those losses do not generate an NOL until fully deductible. Suspended passive losses are carried forward and can only offset passive income or be released upon disposition. When calculating NOLs under §172, only deductible losses impact the NOL, so careful tracking of passive loss limitations is essential to avoid overstating NOLs.
Can a client combine NOLs arising from unrelated business activities and passive losses from rental real estate when planning tax strategies?
NOLs under §172 are calculated after considering passive activity loss limitations of §469. Passive activity losses disallowed in a given tax year are carried forward separately and do not contribute to the NOL. Therefore, NOLs arising from active businesses cannot be combined with suspended passive losses from rental real estate. Effective tax planning must segregate these loss pools to maximize utilization, as combining them improperly can lead to IRS challenges and inaccurate tax positions.
What key questions should I ask my client to effectively advise on NOL planning strategies?
Ask about the nature and timing of loss-generating activities, including whether losses are from active trade or business operations or passive activities subject to §469 limitations. Inquire about prior NOL carrybacks or carryforwards, amended returns filed, and any elections made under §172. Understand their current and projected income streams to optimize the timing of NOL utilization. Also, clarify any involvement in partnerships, S corporations, or other pass-through entities that may affect loss allocation and reporting. These questions help tailor strategies compliant with tax law and aligned with the client’s financial goals.
Professional Disclaimer
The information on this page is intended for licensed tax professionals (CPAs, EAs, and tax attorneys) and is provided for educational and research purposes only. Tax law is complex and fact-specific — all strategies discussed are subject to limitations, phase-outs, and conditions that may not apply to every client situation. Practitioners should independently verify all information against current IRS guidance, Treasury Regulations, and applicable state law before advising clients. This content does not constitute legal or tax advice.
