Net Operating Loss (NOL) Rules: Carryforward, 80% Limitation, and Tax Planning
A net operating loss (NOL) occurs when allowable tax deductions exceed gross income for the year. Under IRC 172, NOLs can be carried forward to offset income in future years. The TCJA made two significant changes to NOL rules: (1) NOLs arising in tax years beginning after December 31, 2017 can only offset 80% of taxable income in the carryforward year (the 80% limitation), and (2) NOL carrybacks were eliminated (with limited exceptions for farming losses). These changes mean a business with a $50,000 NOL carryforward and $60,000 of taxable income in the following year can only use $48,000 of the NOL (80% of $60,000), leaving $2,000 to carry forward further.
Current NOL rules (post-TCJA):
| Rule | Post-TCJA (Current Law) |
|---|---|
| Carryback | Not allowed (except farming: 2-year carryback) |
| Carryforward | Indefinite (no expiration) |
| Limitation | Can only offset 80% of taxable income |
| Remaining 20% | Always taxable (cannot be offset by NOL) |
How the 80% limitation works:
The NOL used is the LESSER of (a) the NOL available or (b) 80% of taxable income.
| Year | Income | NOL Available | 80% Limit | NOL Used | Taxable After NOL | NOL Remaining |
|---|---|---|---|---|---|---|
| 1 | ($40,000) | $0 | N/A | N/A | ($40,000) NOL | $40,000 |
| 2 | $60,000 | $40,000 | $48,000 | $40,000 | $20,000 | $0 |
The full $40,000 NOL is used because it’s less than the 80% limit ($48,000). The 80% cap only binds when the NOL exceeds 80% of income.
When the 80% limit binds (larger NOL):
| Year | Income | NOL Available | 80% Limit | NOL Used | Taxable After NOL | NOL Remaining |
|---|---|---|---|---|---|---|
| 1 | ($100,000) | $0 | N/A | N/A | ($100,000) NOL | $100,000 |
| 2 | $80,000 | $100,000 | $64,000 | $64,000 | $16,000 | $36,000 |
| 3 | $90,000 | $36,000 | $72,000 | $36,000 | $54,000 | $0 |
In Year 2, only $64,000 of the $100,000 NOL is used (80% of $80,000 income). The remaining $36,000 carries to Year 3.
Common NOL sources for small businesses:
- Large Section 179/bonus depreciation deductions in Year 1 (equipment purchase)
- Startup losses (expenses exceed revenue in early months)
- Bad year (lost a major client, weather/disaster impact)
- Expansion costs (new location, hiring, marketing spend)
Section 179 vs. bonus depreciation (NOL creation):
- Section 179: CANNOT create or increase an NOL (limited to taxable income from the business)
- Bonus depreciation: CAN create an NOL (no taxable income limitation)
- If equipment deductions would create a loss: use bonus depreciation (not Section 179) for the loss-creating portion
How do NOLs work in practice for small businesses?
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Yarik Yarosh, CPA. "Net Operating Loss (NOL) Rules: Carryforward, 80% Limitation, and Tax Planning." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-net-operating-loss-carryforward-deduction
This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.