For many self-employed professionals, saving for retirement isn’t as straightforward as simply enrolling in a workplace 401(k). Instead, you may explore options like a Solo 401(k) or a Roth IRA. But here’s the question many ask: Can you contribute to both in the same year?
Watch: Learn how you can contribute to both a Solo 401k and a Roth IRA
The answer is yes—but with important rules and strategies to understand. Let’s break it down.
Understanding the Basics
What is a Solo 401(k)?
A Solo 401(k) is a retirement plan designed for self-employed individuals or business owners with no full-time W-2 employees (other than a spouse). It offers high contribution limits and the flexibility to choose between:
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Pre-tax contributions (deductible today, taxed at withdrawal)
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Roth Solo 401(k) contributions (after-tax today, tax-free at withdrawal)
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Voluntary after-tax contributions (used in strategies like the Mega Backdoor Roth)
- Visit here to learn mor about the various solo 401k contribution types.
What is a Roth IRA?
A Roth IRA is an individual retirement account that allows after-tax contributions. Earnings grow tax-free, and qualified withdrawals are tax-free. Unlike the Solo 401(k), there are income limits for contributing directly to a Roth IRA. For 2025:
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Contribution limit for 2025: $7,000 (or $8,000 if age 50+)
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Eligibility phases out for high earners based on Modified Adjusted Gross Income (MAGI)
Contribution Limits in 2025
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Solo 401(k): Up to $70,000 if under 50, with higher “catch-up” amounts for ages 60–63
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Roth IRA: Up to $7,000 ($8,000 if age 50 or older)
Here’s the key: Contributions to a Solo 401(k) do not reduce your ability to contribute to a Roth IRA. The only limitation on the Roth IRA is your income.
Smart Strategies for Using Both
1. Tax Diversification
By funding both accounts, you balance:
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Pre-tax Solo 401(k) contributions for deductions today
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Roth IRA contributions for tax-free income tomorrow
This mix provides flexibility in retirement—allowing you to manage your taxable income more strategically.
2. Backdoor Roth IRA
If your income is too high for a Roth IRA contribution, you can use the Backdoor Roth IRA strategy:
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Contribute to a non-deductible Traditional IRA
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Convert it to a Roth IRA
If you already have other pre-tax IRAs, you may need to roll those into a Solo 401(k) first to avoid tax complications.
3. Mega Backdoor Roth via Solo 401(k)
Some Solo 401(k) providers allow voluntary after-tax contributions up to the plan’s total annual limit. These funds can then be converted into a Roth Solo 401(k) or a Roth IRA, allowing much larger Roth contributions than the standard IRA limits.
Pitfalls to Avoid
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Income limits for Roth IRA contributions: High earners must use the Backdoor Roth IRA strategy.
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Confusing plan types: Remember, a Solo 401(k) is one plan that can accept multiple contribution types—it’s not separate “plans.”
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Transfer restrictions: You cannot transfer a Roth IRA into a Roth Solo 401(k). However, you can move Roth Solo 401(k) funds into a Roth IRA after a qualifying event (e.g., retirement or leaving self-employment).
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Self-employment requirement: To contribute to a Solo 401(k), you must have self-employment income.
Real-World Example
Let’s say Janet and Bill run an S-Corporation together. Each earns $100,000 in W-2 wages.
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Janet contributes $70,000 via the Mega Backdoor Roth Solo 401(k), converting it immediately into a Roth Solo 401(k).
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Bill contributes $70,000 the same way, indirectly maximizing his Roth contributions via the mega backdoor Roth strategy.
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Both also contribute $7,000 each into their Roth IRAs (because their income falls below the threshold).
In total, they shield $154,000 across tax-advantaged accounts—leveraging both the Solo 401(k) and Roth IRA.
Final Thoughts
Yes—you can have both a Solo 401(k) and a Roth IRA, and in many cases, it’s a powerful combination. The Solo 401(k) gives you high contribution limits and business tax advantages, while the Roth IRA provides tax-free growth and withdrawals.
The best approach depends on your income, tax situation, and retirement goals. For many self-employed individuals, combining the two offers the ultimate retirement savings flexibility.
