What is the 2026 NIIT threshold for a single filer, and how does oil and gas investing help you avoid it?

Quick answer: For single filers in 2026, the net investment income tax (NIIT) threshold is $200,000 of modified adjusted gross income. Above that, a 3.8% tax applies to net investment income. Oil and gas working interests held as active interests are statutorily exempt from NIIT.

What Is the 2026 NIIT Threshold for a Single Filer?

If you file your federal taxes as a single filer in 2026, the Net Investment Income Tax - commonly called the NIIT - applies once your modified adjusted gross income (MAGI) crosses $200,000. At that point, the IRS imposes an additional 3.8% surtax on the lesser of your net investment income or the amount by which your MAGI exceeds that threshold. This threshold has not been indexed for inflation since the NIIT was enacted under the Affordable Care Act in 2013, which means more and more middle-to-upper-income earners are getting pulled into it every year without any change in their real purchasing power.

For married filers the threshold is $250,000, and for married filing separately it drops to $125,000. This FAQ focuses specifically on the single filer threshold of $200,000 and what you can do about it in 2026.

What Income Does the NIIT Actually Tax?

The 3.8% NIIT applies to what the IRS classifies as net investment income, which includes:

• Interest, dividends, and capital gains
• Rental income (unless you qualify as a real estate professional)
• Royalty income from passive arrangements
• Passive business income - including passive oil and gas royalties
• Annuity income not from a trade or business

Wages, self-employment income, and income from an active trade or business are specifically excluded. That last carve-out is exactly where oil and gas working interest investing becomes a powerful planning tool for single filers approaching or exceeding the $200,000 MAGI threshold.

Why Direct Working Interests Are Different from Royalties

Not all oil and gas income is treated the same way under the tax code. There is a critical distinction between a royalty interest and a working interest.

• Royalty interests are passive by nature. The royalty owner bears no operational liability. Income from royalties is generally subject to the NIIT for single filers above $200,000 MAGI.
• Working interests carry unlimited liability for drilling and operational costs. Because of this liability exposure, Congress specifically exempted working interest income from the passive activity rules under IRC Section 469(c)(3). Income and losses from a working interest held through an entity that does not limit your liability are treated as non-passive.

Non-passive income from an active trade or business is not net investment income under IRC Section 1411. That means the 3.8% NIIT does not apply to distributions you receive from a direct working interest program - even if you are a single filer well above the $200,000 threshold.

How the 2026 OBBBA Provisions Strengthen This Strategy

The 2026 One Big Beautiful Budget Act (OBBBA) enhanced several provisions that make direct working interest investing even more attractive for high-earning single filers. The continued availability of 100% Intangible Drilling Cost (IDC) deductions in year one under IRC Section 263(c) means a single filer can take a large above-the-line equivalent deduction that directly reduces MAGI - which is the very number the IRS measures against the $200,000 NIIT threshold. Lower MAGI means less exposure to the surtax, and in some cases it can pull a filer entirely below the threshold.

Combined with the 15% depletion allowance on gross income from the well under IRC Section 613A, investors in programs like Kingdom Exploration's Slocum Hollow project receive ongoing tax-sheltered distributions that are structured to minimize both ordinary income tax and NIIT exposure simultaneously.

Running the Numbers: NIIT Savings for a Single Filer

Consider what the NIIT actually costs a single filer who ignores this planning opportunity. If your MAGI is $350,000 and you have $80,000 in net investment income, the NIIT applies to the lesser of $80,000 (your NII) or $150,000 (the amount above the $200,000 threshold). The lesser amount is $80,000, so your NIIT bill is $80,000 x 3.8% = $3,040 in additional federal tax on top of your regular rate.

Now assume you invest $185,000 into a single unit of the Slocum Hollow program. In year one, you receive a 100% IDC deduction - potentially $148,000 to $166,500 depending on the IDC allocation percentage. That deduction reduces your MAGI directly. If it brings your MAGI below $200,000, your NIIT liability drops to zero. And the monthly distributions you receive - projected at $6,000 to $12,000 per unit - come to you as working interest income, not passive investment income, so they are not subject to the 3.8% surtax going forward either.

What Single Filers Should Do Before Year-End 2026

• Calculate your projected 2026 MAGI before any new investments
• Identify how much of your income is currently classified as net investment income
• Determine whether a working interest IDC deduction could reduce your MAGI below $200,000
• Consult with a tax advisor familiar with IRC 469(c)(3) and IRC 1411 to confirm your specific eligibility
• Review the Q4 2026 deadline for investments to qualify for current-year IDC deductions

For more on year-end timing, see our guide on year-end oil and gas tax deduction strategy for Q4 2026.

Is This Strategy Only for Very High Earners?

No. The NIIT threshold of $200,000 for single filers captures a wide range of professionals - physicians, attorneys, engineers, consultants, and business owners who may not think of themselves as ultra-wealthy but who consistently earn above that level. If you are a W-2 employee with significant investment income on the side, this is especially relevant. See our related FAQ on W-2 employee oil and gas investment tax strategy for 2026 for more detail on how employees specifically can use this approach.

Consult a Qualified Tax Advisor

The interaction between MAGI, the NIIT threshold, IDC deductions, and working interest classification involves multiple IRC sections and your specific fact pattern. Kingdom Exploration recommends working with a CPA or tax attorney who has direct experience with oil and gas working interest taxation before making any investment decision based on tax outcomes. The information here is educational and does not constitute tax or legal advice.