Can You Have Two Solo 401(k) Plans? The Controlled Group Answer
You run a freelance consulting practice as an LLC, and you also own a small e-commerce business. Both are just you, no employees. Two businesses, so two solo 401(k) plans, double the contribution room? That is the question, and the IRS has a specific answer for it. It is not about how many businesses you own. It is about who controls them.
The rule lives in IRC Section 414, the controlled group rules. When one person or a small group owns 80 percent or more of multiple businesses, the IRS treats those businesses as a single employer for retirement plan purposes. Your two businesses are a controlled group. One employer means one set of plan rules, one round of testing, and one combined contribution limit. You cannot set up a second solo 401(k) to get around the limits on the first.
Can you have two solo 401(k) plans if the businesses are unrelated
Two plans are allowed only when the businesses are genuinely separate employers in the IRS's eyes. That happens in a narrow set of cases. The most common one involves spouses: each spouse's business can have its own plan, tested separately, when neither spouse owns any interest in the other's business, neither works for or manages the other's business, and the income tests are met. That is a real exception with real conditions, not a loophole you can improvise.
It also happens when the second "employer" is truly someone else's. A W-2 job plus your side business is the everyday version: your employer's 401(k) and your solo 401(k) are separate plans with separate employer limits. We covered that split in the piece on solo 401(k) limits with a W-2 job.
Why the limits do not double
Here is where the math kills the idea even when two plans exist. The $24,500 employee deferral limit for 2026 is per person, across every 401(k) plan you touch. Defer $24,500 into your W-2 employer's plan and your solo 401(k) deferral for the year is zero. The $72,000 total additions limit applies per employer, and a controlled group counts as one employer. Two plans inside one controlled group share one $72,000 ceiling, not two.
Run the numbers on a single business netting $150,000. Plan compensation after the deductible half of self-employment tax is about $138,800. The employer piece at 20 percent is about $27,760, plus the $24,500 deferral, for roughly $52,260 of total room. Splitting that income across two entities you control does not create a second $72,000 ceiling. It just divides the same income, and the same limit, into two piles of paperwork.
The decision rules
If you own 80 percent or more of both businesses, stop. They are a controlled group, one plan covers both, and every employee of either business counts for eligibility. If one of the businesses has full-time employees who are not you or your spouse, you likely cannot run a solo 401(k) at all. The plan would have to cover those employees, which makes it a regular 401(k).
If the businesses are owned by different people with no attribution between them, separate plans are fine, and each plan gets its own $72,000 employer ceiling. The $24,500 deferral still belongs to you as one person, so coordinate it across the plans before year end.
My take: almost everyone asking this question has a controlled group and does not know it. The two-LLC structure that feels like two businesses is, to the IRS, one employer wearing two hats. Before you open a second plan, map who owns what. The ownership chart decides the answer, not the number of EINs.
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Run your own numbers with the free calculatorFrequently asked questions
Can I have two solo 401(k) plans for two different businesses?
Only if the businesses are truly separate employers under the IRS controlled group rules. If you own 80 percent or more of both, they form a controlled group, count as one employer, and must share a single plan covering both businesses.
What is a controlled group for solo 401(k) purposes?
A group of businesses treated as one employer under IRC Section 414 because of common ownership, generally 80 percent or more. All employees across the group count for plan eligibility and testing.
Do contribution limits double if I have two 401(k) plans?
No. The $24,500 employee deferral limit for 2026 is per person across all plans, and the $72,000 total additions limit applies per employer, with a controlled group counting as one employer.
Can my spouse and I each have our own solo 401(k)?
Yes, when each spouse's business is genuinely separate: neither owns any interest in the other's business, neither works for or manages the other's business, and the income conditions are met. Each plan is then tested separately.
Related: Solo 401(k) Limits When You Also Have a W-2 Job With a 401(k) · Can I Contribute to Both a Solo 401(k) and a SEP IRA in the Same Year? · What Happens to Your Solo 401(k) When You Hire Your First Employee
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