Does the 3.8% net investment income tax apply to rental income?
Usually, yes. The IRS counts rental income as net investment income, so once your modified adjusted gross income passes $200,000 (single) or $250,000 (married filing jointly), you owe 3.8% on the smaller of your net investment income or the amount you are over the line. The main way out for rental profit is the real estate professional safe harbor, which needs more than 500 hours in each rental activity.
The rule in one paragraph
The IRS says individuals owe a 3.8% Net Investment Income Tax on the lesser of their net investment income or the amount by which their modified adjusted gross income exceeds a threshold, and it lists rental and royalty income among the items that count (IRS, Net Investment Income Tax). It is figured on Form 8960 and added to your income tax.
| Filing status | Threshold |
|---|---|
| Married filing jointly | $250,000 |
| Qualifying surviving spouse | $250,000 |
| Single or head of household | $200,000 |
| Married filing separately | $125,000 |
The thresholds do not rise each year. The IRS questions and answers on the tax say plainly that these threshold amounts are not indexed for inflation, so more owners cross them as rents and wages grow.
It is net rental income, not gross rent
The tax applies to net investment income, which the IRS describes as gross investment income reduced by deductions properly allocable to it, including expenses related to rental income. For an apartment building, that means the bottom line of your Schedule E after operating costs, interest and depreciation, not the rent you collected.
The Form 8960 instructions say total income from Schedule E is entered on line 4a, and nonpassive income that is not subject to the tax is backed out on line 4b. A rental that shows a loss for the year adds no net investment income; it can even offset other investment income, subject to the passive loss rules your preparer applies.
A worked example
Example a made-up married couple files jointly. Their modified adjusted gross income is $310,000, which includes $64,000 of net rental income from a 20 unit building and no other investment income. They are $60,000 over the $250,000 threshold. Net investment income is $64,000. The tax is 3.8% of the smaller amount, $60,000, which is $2,280.
Example the same couple has a year with a new boiler and higher interest, and the building nets $18,000. Their modified adjusted gross income falls to $264,000, so they are $14,000 over. The smaller amount is now $14,000, and the tax is $532.
Notice what moved the number: every dollar of real expense that lowers net rental income also lowers income over the threshold. Clean books that capture every deductible cost are worth more for owners in this range.
When rental income is not net investment income
The Form 8960 instructions say rental income is included in net investment income if it is not derived in the ordinary course of a trade or business, and they give owners a safe harbor:
- You qualify as a real estate professional under section 469 (more than half your working time and more than 750 hours in real property businesses in which you materially participate), and
- You participate in each rental real estate activity for more than 500 hours during the year (or met that test in five of the last ten years).
If you qualify, the instructions say your gross rental income from that activity is treated as derived in the ordinary course of a trade or business and is not included in net investment income. A rental activity properly grouped with a trade or business can also be nonpassive. These are fact-heavy tests that need contemporaneous time records; see the passive loss guide for the 750 hour rule, and ask your tax preparer whether you meet them.
Selling the building
The IRS lists gain from the sale of investment real estate as a common example of net investment income. A sale year can push modified adjusted gross income far over the threshold even for owners who never paid the tax before, so model it with your preparer before you sign a contract. A deferred like-kind exchange postpones recognized gain; see the 1031 deadlines guide.
Paying it during the year
The IRS says the Net Investment Income Tax is subject to the estimated tax provisions, so if rental profit pushes you over the threshold you may need to raise your withholding or quarterly estimated payments to avoid an underpayment penalty. The estimated tax guide walks through the dates and safe harbors.
Seeing the number before your preparer does
DoorKeeping keeps each property's books with expense accounts mapped to Schedule E lines, so the net rental figure that feeds Form 8960 is the same one on each property's profit and loss. You can ask your AI app for year-to-date net income across all your properties in September and give your tax preparer time to plan. DoorKeeping does not compute your personal tax or give tax advice.
Sources
- IRS, Net Investment Income Tax, read Oct 30, 2026
- IRS, Questions and answers on the Net Investment Income Tax, read Oct 30, 2026
- IRS, Instructions for Form 8960, read Oct 30, 2026
Questions
- Is the net investment income tax threshold indexed for inflation?
- No. The IRS says the $200,000, $250,000 and $125,000 thresholds are not indexed for inflation.
- Is it 3.8% of all my rent?
- No. It is 3.8% of the smaller of your net investment income, which for rentals is net of expenses and depreciation, or the amount your modified adjusted gross income is over the threshold.
- Can a real estate professional avoid the 3.8% tax on rental income?
- Possibly. The Form 8960 instructions give a safe harbor for real estate professionals who participate more than 500 hours in each rental activity; ask your tax preparer whether you qualify.