A self-directed IRA (SDIRA) is a traditional or Roth IRA that holds alternative assets beyond stocks and bonds: real estate, private equity, cryptocurrency, IRS-approved precious metals, private loans, and tax liens. All standard IRA rules still apply, including IRC Section 4975's prohibited transaction rules. Violating those rules can disqualify the entire IRA, triggering immediate tax and penalties on the full account balance. A Solo 401(k) (also called an individual 401(k) or i401k) is a retirement plan for self-employed individuals with no full-time employees other than a spouse, combining employee deferral and employer profit-sharing slots in a single account.

Direct answer: A self-directed IRA or Solo 401(k) lets you hold alternative assets (real estate, private placements, precious metals, and other non-publicly-traded investments) inside a tax-advantaged retirement account. The IRS allows this under IRC 408 and 401, but the prohibited transaction rules under IRC 4975 are strict: any deal involving yourself, your spouse, or close business partners can disqualify the entire account, triggering immediate tax and penalties on the full balance.

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Self-Directed IRAs and Solo 401(k)s: What Investors Need to Know

What Assets Can a Self-Directed IRA Hold?

A conventional IRA held at a mainstream brokerage is limited to securities that custodian can price and hold: stocks, bonds, mutual funds, ETFs, and CDs. A self-directed IRA uses a specialized custodian that allows a broader universe, but the IRS defines both what is allowed and what is explicitly prohibited.

Allowed asset types in a self-directed IRA include:

Prohibited asset types under IRC Section 408 include:

Owning a prohibited asset inside an IRA triggers immediate deemed distribution of the asset's fair market value, which is taxed as ordinary income plus a 10% early withdrawal penalty if the owner is under 59.5. The restriction applies to the entire IRA, not just the prohibited portion.

Prohibited Transactions: IRC Section 4975

Section 4975 of the Internal Revenue Code prohibits any direct or indirect transaction between an IRA and a "disqualified person." This is the most dangerous rule for self-directed IRA owners because violations are easy to make and the penalty is catastrophic.

Who counts as a disqualified person?

Note: siblings, cousins, and friends are generally not disqualified persons.

Examples of prohibited transactions

The penalty: entire IRA disqualified

If a prohibited transaction occurs, the IRA is treated as fully distributed as of January 1 of the year in which the violation occurred. That means the entire account balance (not just the amount involved in the transaction) becomes taxable as ordinary income in that year, plus a 10% early withdrawal penalty applies to the full balance if the owner is under age 59.5. A $300,000 IRA can become a $300,000 tax bill in a single year from one mistake.

The Custodian Requirement

Every IRA, self-directed or otherwise, must have a custodian: a bank, credit union, or IRS-approved non-bank trustee. For conventional IRAs, that custodian is typically a brokerage firm. For SDIRAs, you need a specialized custodian that permits alternative assets.

Examples of SDIRA custodians include Equity Trust Company, New Direction Trust Company, and Millennium Trust Company. These custodians charge more than mainstream brokerages: expect annual maintenance fees of $200 to $500 or more, plus per-transaction and per-asset fees.

Custodians are passive. This is a critical point that leads to many SDIRA mistakes. The custodian holds the assets and processes transactions at your direction. It does not evaluate whether your investments are sound, whether the seller is legitimate, or whether a transaction is legal. All due diligence is entirely your responsibility. Fraud cases involving SDIRAs often exploit this passivity: the investor assumes the custodian would not allow an improper investment, but the custodian simply holds what the investor tells it to hold.

Unrelated Business Taxable Income (UBTI)

Normally, IRAs grow tax-deferred without current taxation. But if an IRA-owned asset generates Unrelated Business Taxable Income, the IRA itself owes tax (UBIT) on that income at trust tax rates, which reach the top bracket quickly. Two common SDIRA situations triggering UBTI:

UBTI is reported on Form 990-T and the tax is paid by the IRA, reducing the account balance. This eliminates much of the tax advantage for leveraged real estate inside an IRA.

Solo 401(k): For the Self-Employed

A Solo 401(k) (also called an individual 401(k) or i401k) is a standard 401(k) plan available to self-employed individuals and business owners with no full-time employees other than a spouse. It combines two contribution slots that make it especially powerful for high-income self-employed people.

Eligibility

You must have self-employment income: from a sole proprietorship, partnership, LLC, or S-corp. You cannot have full-time W-2 employees other than a spouse. Part-time employees working under 1,000 hours per year generally do not disqualify you. Owners of multiple businesses need to aggregate plans across businesses under common control rules.

2026 contribution limits

The high limit makes the Solo 401(k) the most powerful retirement savings vehicle available to self-employed individuals who have significant income, outpacing a SEP-IRA at lower income levels once the employee deferral slot is factored in.

Additional features

Solo 401(k) plans can be self-directed (holding alternative assets) if the plan document allows it and you establish the right custodial arrangement. The same prohibited transaction rules apply.

Who Actually Benefits from an SDIRA?

Self-directed IRAs are appropriate in specific, narrow circumstances. They are not suitable for most retail investors, and the gap between marketing claims and reality is wide.

SDIRAs make sense for: Investors with genuine, specific expertise in an alternative asset class (for example, a real estate investor who already owns and manages properties outside their IRA), who understand the prohibited transaction rules in detail, and for whom the higher fees, illiquidity, and valuation challenges are acceptable tradeoffs to hold that specific asset class inside a tax-advantaged account.

SDIRAs do not make sense for: Average retail investors seeking "better returns" through alternatives without deep expertise in those assets. Common failure modes include overpaying for hard-to-value assets (private equity, real estate, precious metals) because there is no market price to verify the purchase was fair, and inadvertently triggering a prohibited transaction through what seemed like a routine management decision.

Fraud risk

The SEC has explicitly warned that self-directed IRAs are disproportionately represented among victims of Ponzi schemes and investment fraud. The mechanics are straightforward: an SDIRA allows investment in things that are not exchange-traded and therefore difficult to verify, the custodian provides no investment oversight, and the investor tends to defer to whoever introduced the investment. Promoters exploit all three of these features.

Before opening an SDIRA, verify the investment independently (not through the same promoter), review the custodian on the IRS approved non-bank trustee list, and consult a tax professional who specializes in self-directed plans about the prohibited transaction rules specific to your intended strategy.

Frequently Asked Questions

What is a self-directed IRA?

A self-directed IRA is a traditional or Roth IRA that allows investment beyond publicly traded stocks, bonds, and mutual funds into alternative assets such as real estate, private equity, cryptocurrency, IRS-approved precious metals, private loans, and tax liens. The term "self-directed" is a marketing description, not a separate legal category: the account follows all standard IRA rules, including contribution limits, prohibited transaction rules under IRC Section 4975, and required minimum distribution requirements. The distinction from a conventional IRA is the custodian: a self-directed IRA uses a specialized custodian that permits alternative assets, whereas most mainstream brokerage custodians restrict accounts to securities they can custody and price.

What is a prohibited transaction in a self-directed IRA?

IRC Section 4975 defines a prohibited transaction as any direct or indirect transaction between an IRA and a disqualified person. Disqualified persons include the IRA owner, the owner's spouse, lineal descendants and ancestors, fiduciaries, and service providers to the IRA. Examples of prohibited transactions include purchasing real estate from yourself and selling it to your IRA, using IRA-owned property personally even for a single night, lending IRA funds to yourself, and hiring your own business as a service provider to an IRA-owned property. The penalty for a prohibited transaction is severe: the entire IRA is treated as fully distributed as of January 1 of the year the violation occurred, making the full account value taxable as ordinary income, plus a 10% early withdrawal penalty if the owner is under age 59.5.

Who should use a self-directed IRA?

Self-directed IRAs are appropriate for investors who have genuine, specific expertise in an alternative asset class that is not available through conventional brokerage accounts, and who understand the prohibited transaction rules well enough to avoid accidentally triggering them. Most retail investors are better served by conventional IRA accounts: self-directed IRAs carry higher custodian fees (often several hundred dollars per year plus per-transaction fees), assets are difficult to value accurately and may be illiquid, and the catastrophic penalty for a prohibited transaction can destroy the entire retirement account's tax-advantaged status. The SEC has warned that self-directed IRAs are disproportionately represented in Ponzi scheme and investment fraud cases, because the self-directed structure creates less broker oversight than a conventional account.

References

Swoopr Editorial Team

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