How to choose the right self-directed plan

Are you eligible for a Solo 401(k)?

Start here, since eligibility settles the question faster than any feature comparison. The Solo 401(k) is available only to self-employed individuals whose business has no full-time, non-owner employees other than a participating spouse. Everyone else chooses between the IRA LLC and the IRA Trust, which is not a downgrade; for most investors, an IRA structure does everything they need. For the full eligibility test, including the common-law employee and controlled-group rules, see Solo 401(k) eligibility: key things to know.

Even qualifying investors should check whether they'll actually use what sets the Solo 401(k) apart. Higher contribution capacity, a participant loan, and the UDFI exemption on debt-financed real estate are real advantages, but the Solo 401(k) also puts you in the plan administrator role, tracking beneficiaries and handling reporting that a custodian manages for you under an IRA. Important: if you qualify but won't use those features, a Checkbook IRA with a custodian managing that administrative layer may suit you better.

Are your funds compatible with the plan you're considering?

Before settling on a structure, check what the money itself allows, since compatibility rules can override preference entirely. Two things matter: whether each funding source can enter the plan you're considering, and whether your sources are compatible with each other. A Roth IRA and an inherited IRA cannot roll into a Solo 401(k); that money has to stay in an IRA structure. Funds with different tax treatment generally can't be combined, and a SIMPLE IRA less than two years old can only move to another SIMPLE IRA.

A Solo 401(k) is more flexible here than an IRA: it can hold funds from both spouses within one plan, while each spouse's IRA funds require a separate account. In practice, the most common misstep we see is an investor selecting a structure on features alone, before checking whether the funds they actually plan to move are compatible with it. When funds aren't fully compatible, you either run two plans or move forward with the compatible portion and handle the rest separately.

What do you want to invest in?

The asset you have in mind is often the clearest signal, because the driving factor is liability exposure. Direct real estate, where you own and manage property with public access, belongs in a structure that puts a legal boundary around that risk: an IRA LLC, or a Solo 401(k) if you qualify and are using leverage. Paper assets, including cryptocurrency, private notes, and passive syndications, carry no direct liability exposure and suit the IRA Trust, or a Solo 401(k) for those who qualify. The structure never changes what you're allowed to invest in; it changes how you're protected, what the plan costs to operate, and how visible it is. For the full breakdown, including foreign real estate and multi-state considerations, see IRA Trust vs IRA LLC.

Will the plan still fit a few years from now?

The plan that fits today is the right one only if it still fits where you're heading. This matters most for the Solo 401(k), since eligibility is tied to ongoing self-employment. A plan that suits you now can become a liability if you plan to hire full-time employees, wind down the business, or retire soon; when eligibility ends, the plan has to be terminated and the balance rolled to an IRA. That termination paperwork is a common source of avoidable friction, and it's easy to underestimate if you weren't watching for it. An IRA structure carries no such dependency and never requires termination because your income or staffing changed.

Can you run more than one plan at once?

Yes, and it's a normal outcome, not a sign the decision process went wrong. Asset segregation is one common reason: an investor might hold an IRA LLC for a rental property and an IRA Trust for paper assets, keeping the liability-exposed asset walled off from the rest. Spouses are another case, since each spouse's IRA funds are separate. A third case shows up for investors who qualify for a Solo 401(k) but also hold Roth IRA money they want self-directed; since a Roth IRA cannot roll into a Solo 401(k), it's common to run the Solo 401(k) for new contributions alongside a separate Roth Checkbook IRA.

Who should give you a recommendation?

A tool can narrow the field, and a comparison can explain the trade-offs, but a recommendation built around your full picture, your tax situation, your estate plan, your risk tolerance, is the work of a licensed professional: a financial advisor, a CPA, or an attorney. Those credentials exist because personalized advice carries responsibility, and the license is what holds the person accountable for what they tell you. At many providers, the person guiding you toward a decision is a sales consultant, and a title like "specialist" is not a license. Our role is to give you the structure and the plain facts to compare on your own.

Next Steps

Answer the four questions above using the Plan Finder, or browse the full set of plan comparisons to read through each pairing directly.