Net Investment Income Tax on Syndication Income: Who Owes the 3.8%
On this page
Yes, for many higher-income investors. The net investment income tax (NIIT) is a 3.8% federal tax on the lesser of your net investment income or the amount your modified adjusted gross income (MAGI) is above a threshold. A limited partner's share of rental income from a syndication is generally net investment income because it is passive, and so is gain when the building sells. Cash distributions that only return your capital are not income, so they are not taxed by themselves.
This post is for investors who see "Form 8960" on a tax return or wonder why a K-1 raised their bill. It is general information as of October 2026, not tax advice; ask your own tax adviser.
What counts as net investment income from a syndication?
For a limited partner, the K-1 items that usually count are rental income (Box 2), interest and dividends, and gain from selling the building or the interest. Capital gain and Section 1231 gain flow through as investment income when the activity is passive. See the K-1 guide line by line. Deductions tied to that income, such as depreciation allocated to you, reduce it.
Does a distribution trigger the tax?
Not by itself. A distribution is cash. The tax follows the income on your K-1, not the cash you received. If a distribution is a return of capital, it lowers your basis and is not NIIT income until it exceeds basis. Read are syndication distributions taxable? and the capital account on a K-1.
How does the threshold work? An example
This is a hypothetical example, not a tax calculation. Two married couples filing jointly each have $20,000 of net investment income from a syndication.
| Case | MAGI | Amount over $250,000 | NIIT base (lesser of $20,000 or the excess) | NIIT at 3.8% |
|---|---|---|---|---|
| Couple A | $240,000 | $0 | $0 | $0 |
| Couple B | $265,000 | $15,000 | $15,000 | $570 |
Couple B owes on the smaller amount. If either couple's syndication had produced a net loss, there would be no net investment income from it that year and the loss would follow the passive loss rules (see passive loss carryover).
Can a real estate professional avoid it?
The tax does not apply to income from a trade or business that is not a passive activity. If you qualify as a real estate professional and materially participate in the rental activity, your rental income may not be net investment income. A syndication investor who writes a check and receives a K-1 is generally passive. See real estate professional status. The hours tests are strict, and the sponsor, not the investor, usually runs the property.
What can an investor do?
- Ask your CPA to compute Form 8960 with your K-1 before the sale year, not after.
- Track your basis and suspended losses each year.
- In a sale year, model MAGI with and without the gain.
- Remember that state tax may apply on top. See state tax returns for nonresident investors.
How DoorRaise fits in
DoorRaise helps sponsors raise equity for apartment buildings from their friends and followers under Rule 506(b) or 506(c). The deal's accountant prepares the K-1s; DoorRaise delivers each K-1 to the investor, which the $5,000 yearly administration fee covers, and gives no tax advice. Fees: $1,500 to set up (non-refundable), then $5,000 a year from closing (only if the deal closes). See investor reporting and pricing.
FAQ
Do syndication investors pay the net investment income tax?
If their MAGI is above the threshold and the K-1 produces net investment income, yes. Many investors below the threshold do not.
Is NIIT in addition to capital gains tax?
Yes. It is separate from regular income and capital gains tax and is calculated on Form 8960.
Does depreciation reduce the NIIT?
It reduces the rental income allocated to you, so it reduces net investment income, but it comes back in a sale year as gain.
Is a return of capital subject to NIIT?
Not while it is a return of your basis. Amounts above basis are gain and may be.
Is the NIIT threshold indexed for inflation?
No. The statute sets fixed dollar amounts.
Sources
- IRS: Net Investment Income Tax
- 26 U.S.C. 1411: Imposition of tax (Cornell LII)
- IRS: Publication 925, Passive Activity and At-Risk Rules
- IRS: Partners' Instructions for Schedule K-1 (Form 1065)
This article is general information as of October 2026, not tax, legal or investment advice. The example is hypothetical. Ask your own tax adviser. DoorRaise is not a law firm, broker-dealer, investment adviser or funding portal.