Quick Answer
The net investment income limitation subjects investment income to an additional 3.8% tax for individuals earning over $200,000 ($250,000 married filing jointly). This applies to interest, dividends, capital gains, and rental income, potentially adding thousands in unexpected taxes.
Best Answer
Michelle Woodard, Tax Policy Analyst
Best for investors with significant investment income who may be subject to NIIT
What triggers the net investment income tax?
The net investment income tax (NIIT) is an additional 3.8% tax that applies when two conditions are met: your modified adjusted gross income (MAGI) exceeds certain thresholds AND you have net investment income. For 2026, the thresholds are $200,000 for single filers, $250,000 for married filing jointly, and $125,000 for married filing separately.
Example: How NIIT affects your tax bill
Let's say you're single with $220,000 in salary and $30,000 in investment income (dividends and capital gains). Your MAGI is $250,000, which exceeds the $200,000 threshold by $50,000. The NIIT applies to the lesser of:
You'll pay 3.8% NIIT on $30,000 = $1,140 in additional taxes.
What counts as net investment income?
Subject to NIIT:
NOT subject to NIIT:
NIIT calculation comparison table
Strategies to reduce NIIT exposure
Tax-advantaged investments:
Retirement account optimization:
Business structure planning:
What you should do
If your MAGI approaches the thresholds, run projections using our refund estimator to model different scenarios. Consider working with a tax professional to implement NIIT reduction strategies before year-end. The key is planning ahead — most NIIT reduction strategies require action during the tax year, not at filing time.
Key takeaway: NIIT adds 3.8% to investment income for high earners, but proper planning can significantly reduce exposure through strategic asset allocation and retirement account optimization.
*Sources: [IRC Section 1411](https://www.law.cornell.edu/uscode/text/26/1411), [IRS Publication 550](https://www.irs.gov/pub/irs-pdf/p550.pdf)*
Key Takeaway: NIIT adds 3.8% tax on investment income for high earners, but strategic planning with tax-advantaged investments and retirement contributions can significantly reduce exposure.
NIIT thresholds and calculation examples for different filing statuses
| Filing Status | MAGI Threshold | Example MAGI | Investment Income | NIIT Calculation | Additional Tax |
|---|---|---|---|---|---|
| Single | $200,000 | $240,000 | $25,000 | 3.8% × $25,000 | $950 |
| Single | $200,000 | $240,000 | $50,000 | 3.8% × $40,000 | $1,520 |
| Married Filing Jointly | $250,000 | $300,000 | $35,000 | 3.8% × $35,000 | $1,330 |
| Married Filing Jointly | $250,000 | $300,000 | $60,000 | 3.8% × $50,000 | $1,900 |
| Married Filing Separately | $125,000 | $150,000 | $20,000 | 3.8% × $20,000 | $760 |
More Perspectives
Robert Kim, Tax Return Analyst
Best for business owners who need to understand how business income affects NIIT
How business structure affects NIIT
As a business owner, your entity structure determines whether income is subject to NIIT. The key distinction is "active" versus "passive" participation.
Active business income (NOT subject to NIIT):
Passive income (subject to NIIT):
Material participation test
According to IRS regulations, you materially participate if you meet any of these tests:
Example: You own a 30% stake in a consulting LLC, work 200 hours annually, and other partners work 800+ hours each. Your $50,000 share likely qualifies as passive income subject to NIIT if your MAGI exceeds thresholds.
Planning opportunities
S-corp election benefits:
Converting from LLC to S-corp can help. S-corp distributions from active businesses aren't subject to NIIT, while LLC income might be.
Real estate professional status:
If you qualify as a real estate professional (750+ hours annually, more than any other activity), rental income becomes active and avoids NIIT.
Key takeaway: Business owners can often avoid NIIT through proper entity structure and documented material participation, but the rules are complex and require careful planning.
Key Takeaway: Business structure and material participation documentation are crucial for avoiding NIIT on business income — S-corp election and real estate professional status offer significant opportunities.
Michelle Woodard, Tax Policy Analyst
Best for professionals with high W-2 income plus investment income
NIIT planning for high-earning professionals
As a high-earning professional, you likely face NIIT if you have significant investment income alongside your salary. The challenge is that you can't easily reduce your W-2 income, so planning focuses on managing investment income timing and character.
Year-end tax planning strategies
Harvest losses strategically:
If you're subject to NIIT, tax-loss harvesting becomes more valuable. A $10,000 capital loss saves you regular income tax PLUS 3.8% NIIT — potentially worth $4,180+ in tax savings for high earners.
Time capital gains:
Maximize retirement contributions:
Every dollar in pre-tax retirement accounts reduces MAGI:
Example calculation:
Surgeon earning $300,000 with $40,000 investment income. MAGI exceeds threshold by $50,000, so NIIT applies to full $40,000 = $1,520. By maxing 401(k) ($23,500), MAGI drops to $276,500, excess becomes $26,500, NIIT drops to $1,007 — saving $513.
Key takeaway: High-earning professionals should focus on maximizing pre-tax retirement contributions and strategic investment timing to minimize NIIT exposure while building wealth.
Key Takeaway: High earners should maximize pre-tax retirement contributions and strategically time capital gains to reduce MAGI and minimize the 3.8% NIIT on investment income.
Sources
- IRC Section 1411 — Net Investment Income Tax statute
- IRS Publication 550 — Investment Income and Expenses
Reviewed by Michelle Woodard, Tax Policy Analyst on February 28, 2026
This content is for educational purposes only and is not a substitute for professional tax advice. Consult a qualified tax professional for advice specific to your situation.