Why Holding MLPs in an IRA Trigger Unrelated Business Taxable Income?

Master limited partnerships (MLPs) are beloved by income-focused investors for their high yields, often exceeding 7–10% annually. The tax efficiency of MLPs in taxable accounts—through depreciation deductions passed to unitholders—makes them an appealing core holding for many portfolios. But the moment you place an MLP inside an IRA, you unlock a hidden tax trap: unrelated business taxable income (UBTI). IRAs are meant to shelter investment returns from taxation, yet MLPs held in IRAs generate taxable distributions that force the IRA itself to pay income tax, eroding the retirement account's core advantage. Many investors discover this only at tax time, finding a surprise tax bill and Form 990-T obligations they never expected.

Quick definition: Unrelated business taxable income (UBTI) is income from an active trade or business that a tax-exempt entity—including an IRA—must report and pay tax on. MLPs in IRAs generate UBTI because the IRA receives partnership business income, not passive investment income.

Key takeaways

• IRAs are tax-exempt entities; UBTI rules prevent them from sheltering active business income, only passive investment returns.
• MLPs generate partnership K-1 income that the IRS treats as active business income, triggering UBTI even when held inside an IRA.
• UBTI is taxed at trust tax rates, which reach 37% on income over about $14,500, higher than individual rates on the same income.
• MLPs held in IRAs require filing Form 990-T (Exempt Organization Business Income Tax Return) each year, adding compliance burden.
• The UBTI threshold is $1,000 annually; any UBTI above that triggers both income tax and Form 990-T filing.
• Roth IRAs are not exempt; UBTI in Roth IRAs is also taxable, though it reduces the account's tax-free growth.
• Most individual investors should hold MLPs in taxable brokerage accounts, where K-1 distributions are taxed at favorable rates.

What Is Unrelated Business Taxable Income?

The IRA and other tax-exempt entities enjoy a special privilege: they pay no federal income tax on investment returns. This privilege rests on a social policy: these entities serve public or retirement purposes, so society subsidizes them through tax exemption. But Congress never intended IRAs to shelter active business income. An IRA that runs a bakery or consulting practice should not escape taxation on those business profits. So Congress created the unrelated business taxable income rules to tax IRAs and other exempt entities on active trade or business income, even though the entity is otherwise tax-exempt.

UBTI is income derived from:

1. An active trade or business (not passive investment)
2. Regularly carried on by the tax-exempt entity
3. Not substantially related to the entity's exempt purpose

For most IRAs, UBTI is rare. A typical IRA holds stocks, bonds, and mutual funds—all passive investments generating dividends and interest, which are not UBTI. But certain investments, particularly partnerships and S-corporations engaged in operating businesses, throw off UBTI to their equity holders.

Why MLPs Generate UBTI

MLPs are entities organized to own and operate infrastructure assets—pipelines, storage terminals, natural gas systems, renewable energy plants. They are not passive investment vehicles; they actively conduct a business of transporting, processing, and selling commodities. The IRS views the partnership's business operations as generating active business income that flows to unitholders via K-1 forms.

When you hold MLP units directly in a taxable account, the K-1 income is subject to pass-through taxation at your individual rate (15–37% depending on your bracket). But when those same K-1 distributions flow to an IRA, the IRS does not allow the IRA to treat them as passive. The partnership's business activities don't change because the investor is tax-exempt. The income remains active business income in the IRA's hands, triggering UBTI.

A concrete example: Enbridge Inc. (ENB), a large oil and gas pipeline MLP, distributed $1.50 per unit in 2023. If you owned 100 units in a taxable account, you'd receive K-1 income and likely benefit from depreciation deductions, reducing your taxable gain. But if those 100 units are held in an IRA, the IRA receives the same distributions, and $150 of that is UBTI. The IRA must pay tax on it at trust rates—a direct cost to the account's growth.

How UBTI Is Taxed and Reported

UBTI is taxed at trust and estate tax rates, not individual rates. For 2024, the trust tax brackets are:

Taxable Income	Tax Rate
$0–$3,050	10%
$3,050–$11,350	12%
$11,350–$14,050	22%
$14,050+	37%

Compare this to individual 2024 brackets, where 37% doesn't kick in until nearly $600,000 of income. An IRA with $50,000 in annual UBTI faces a 37% marginal rate, whereas an individual with $50,000 of ordinary income pays only 22%. This rate structure makes UBTI especially costly for retirees drawing moderate income.

To report UBTI, the IRA custodian (your brokerage or IRA administrator) must file Form 990-T with the IRS. This form is separate from your personal 1040. The IRA itself becomes a filing entity, adding complexity and potential penalties if the form is late or incorrect. The threshold for filing is $1,000 of UBTI; below that, no Form 990-T is due, but the IRA still owes tax on the UBTI.

The tax is paid from the IRA account itself, reducing the balance available for retirement. If your IRA earns $40,000 and $10,000 is UBTI, the IRA pays roughly $3,700 in UBTI tax at trust rates, leaving $6,300 of net growth to reinvest. The same investment in a taxable account would have generated no IRA-level tax, only personal income tax on distributions.

Decision tree for UBTI in IRAs

Real-world examples

Example 1: MLP in a traditional IRA. Mark owns 500 units of Energy Transfer (ET), a major midstream MLP, in his traditional IRA. ET distributes $1.80 per unit annually, paying Mark $900 in cash distributions from his IRA. Of that, $600 is ordinary income on the K-1 (the rest is return of capital). Mark's IRA reports $600 as UBTI. Since $600 is below the $1,000 threshold, the IRA does not file Form 990-T, but it still owes tax on the $600. At a 24% trust rate, the IRA pays $144, reducing its balance. Over 20 years of accumulation, the annual $144 tax bill compounds to thousands of dollars in lost growth—all avoidable had Mark held ET in a taxable account where he'd pay long-term capital gains rates instead.

Example 2: UBTI threshold trigger. Sarah holds MLP units in her Roth IRA worth $200,000. Her annual distributions total $15,000, of which $12,000 is ordinary K-1 income (above the $1,000 threshold). Her Roth IRA must file Form 990-T. Assuming a 32% trust rate, the IRA owes $3,840 in UBTI tax. Because it's a Roth IRA, the tax doesn't reduce her future distributions (contributions are already made with after-tax dollars), but it does reduce the account's compounding balance. Over 25 years until withdrawal, that $3,840 annual drain plus the lost growth on it could eliminate $150,000+ of retirement wealth.

Example 3: Mixed portfolio with partial UBTI. James holds both stocks and MLP units in an IRA. His dividend stocks generate $8,000 annually—no UBTI, all passive. His MLP units throw off $4,000 in K-1 income annually. His IRA reports $4,000 UBTI (above the $1,000 threshold), triggering Form 990-T. The $8,000 in stock dividends remain tax-free to the IRA. Only the $4,000 partnership income is taxable. At a 24% rate, the IRA pays $960, reducing overall growth by that amount annually.

Common mistakes

1. Assuming all MLP distributions are return of capital and tax-free. Many MLPs distribute a portion classified as return of capital on the K-1, reducing your cost basis rather than generating taxable income. Investors often mistakenly assume all distributions are non-taxable return of capital. In reality, a typical MLP might distribute $1.00 per unit, of which $0.60 is ordinary income and $0.40 is return of capital. Only the $0.60 is UBTI; the $0.40 is not. Failing to separate the two leads to either overstating or understating UBTI.

2. Holding high-yield MLPs in Roth IRAs and forgetting about UBTI. Many investors believe Roth IRAs are completely tax-free, even on business income. While Roth distributions are tax-free, UBTI inside a Roth is still taxable to the account itself. A Roth with $15,000 in annual MLP-generated UBTI will pay roughly $3,600–$5,000 in trust-rate tax, permanently reducing the account. The tax-free status of distributions doesn't eliminate tax on the underlying UBTI.

3. Not checking the K-1 to identify UBTI components. The MLP's K-1 (Schedule K-1, Form 1065) itemizes ordinary business income, capital gains, depreciation deductions, and other items. Ordinary business income is UBTI; capital gains from the partnership generally are not. Some investors never read the K-1, instead assuming all distributions are the same. Reading line 1a (ordinary business income) versus lines 5a–d (capital gains) tells you exactly how much UBTI your IRA faces.

4. Failing to file Form 990-T and incurring penalties. If your IRA generates over $1,000 in UBTI, Form 990-T must be filed by the 15th day of the ninth month following the tax year (roughly June 15). Many IRA custodians do not automatically handle this; you may need to request it or file it yourself. Missing the deadline incurs late-filing penalties and penalties for not paying the tax.

5. Using debt to fund MLP purchases in an IRA and doubling UBTI. Some IRAs use leverage (borrowed money) to purchase investments. If you use debt to buy MLPs in an IRA, you generate not only UBTI from the MLP's business income but also unrelated debt-financed business income (UDBTI), which is UBTI on the portion of income attributable to debt-financed assets. This can double the tax hit and is rarely advisable.

FAQ

Are all MLPs problematic in IRAs, or just high-yield ones?

All MLPs generate UBTI to IRAs, regardless of yield. A low-yield MLP still carries the cost of UBTI taxation. However, the economic impact depends on the ratio of UBTI to total return. A 3% yielding MLP with $1,000 of UBTI is less punitive than a 10% yielding MLP with $5,000 of UBTI. But the fundamental issue—active business income taxed at trust rates—applies to all MLPs in IRAs.

Can I hold MLP mutual funds or ETFs in an IRA to avoid UBTI?

MLP ETFs and mutual funds that hold only MLPs still pass through UBTI to investors. However, diversified funds or index funds that include MLPs alongside stocks and bonds may have lower UBTI penetration since the fund's overall return is spread across many asset classes. If you must hold MLPs in an IRA, a fund approach may be preferable to direct unit ownership, but it doesn't eliminate UBTI entirely.

What about preferred shares or bonds issued by energy companies instead of MLPs?

Preferred shares and bonds issued by corporations (not partnerships) do not generate UBTI in an IRA. Preferred shares from Energy Transfer or Enbridge, if issued by the corporate subsidiaries rather than partnership units, would generate ordinary dividend income with no UBTI component. Check the security's structure; if it's issued by a corporation (Inc. or Corp.), not an LP or MLP, UBTI is unlikely.

If I have UBTI, can I still contribute to the IRA?

UBTI does not affect contribution eligibility. You can continue to make annual contributions to an IRA even if the account has UBTI. However, the ongoing UBTI tax is a drag on growth that might suggest reconsidering the MLP holdings themselves.

What if my IRA is invested in a partnership that has MLP holdings?

If your IRA invests in a fund or partnership that itself invests in MLPs, you inherit the UBTI. The intervening fund does not insulate you from UBTI; the IRS looks through to the underlying assets. If Fund X owns MLP units and distributes K-1 income to you as the investor, that K-1 income is UBTI in your IRA.

Is it worth moving MLPs to a taxable account to avoid UBTI?

For most investors, yes. In a taxable account, MLP distributions are taxed at your individual rate (long-term capital gains rates apply to return of capital and may apply to some business income; depreciation deductions further reduce your tax bill). The effective rate is often lower than the trust rate applied to UBTI. The trade-off is that you lose tax deferral on the earnings, but UBTI removes that benefit anyway.

How do I calculate UBTI if my MLP distributions are irregular?

UBTI is based on the ordinary business income reported on the K-1, not on cash distributions. An MLP may distribute cash quarterly, but the K-1 at year-end shows the total ordinary income for the year. Use the K-1, not the distribution receipts, to calculate UBTI. If the K-1 shows $5,000 of ordinary income, that's your UBTI amount.

Related concepts

• MLP and K-1 Taxation: Partnership Pass-Through Income — covers MLP structure and K-1 taxation in detail.
• Tax-Advantaged Accounts: 401(k), IRA, and HSA — explains how tax-exempt accounts should operate and which investments pair well.
• Capital Gains: Short-Term vs. Long-Term — MLPs sometimes generate capital gains; understanding the distinction aids proper K-1 reading.
• Real Estate Investment Trusts (REITs): Income and Taxation — REITs can also generate UBTI; the same principle applies.
• International Investments and Foreign Withholding Taxes — some foreign partnerships also generate UBTI.

Summary

Holding master limited partnerships in an IRA, whether traditional or Roth, triggers unrelated business taxable income at the trust level, eliminating the account's primary tax-shelter advantage. The UBTI is taxed at rates reaching 37%, higher than individual rates on the same income, and requires filing Form 990-T if UBTI exceeds $1,000 annually. Investors drawn to MLPs for high yields should hold them in taxable brokerage accounts, where K-1 distributions and depreciation deductions are taxed more favorably. Placing MLPs inside an IRA transforms a tax-efficient investment into a tax drag that erodes decades of retirement savings growth. Confirm your IRA's current holdings with your custodian and review K-1s to identify any hidden UBTI; if present, moving those positions to a taxable account often recovers thousands of dollars annually.

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