SEP IRA vs Solo 401(k): Which Retirement Plan Saves Freelancers More in 2026

As a freelancer or self-employed professional, you have access to retirement plans that are far more powerful than a standard workplace 401(k). Two of the most popular options — the SEP IRA and the Solo 401(k) — allow you to stash away tens of thousands of dollars each year on a tax-advantaged basis. But they work very differently, and choosing the wrong one could mean leaving significant tax savings on the table.

In 2026, the IRS increased contribution limits across the board, making both plans even more attractive. The SEP IRA maximum contribution rose to $72,000, and the Solo 401(k) total contribution limit (employee plus employer) also hit $72,000. But the Solo 401(k)’s unique structure — combining employee elective deferrals with employer profit-sharing contributions — means it lets you contribute far more at lower income levels. This guide breaks down every difference, shows you exactly how much you can save with each plan, and gives you a clear decision framework.

2026 Contribution Limits at a Glance

Before diving into strategy, here are the hard numbers for 2026, based on the IRS cost-of-living adjustments announced in Notice 2025-67:

The key difference jumps out immediately: the SEP IRA has no employee contribution component. Every dollar goes in as an employer contribution, capped at 25% of compensation. The Solo 401(k) lets you contribute as both employee and employer, meaning you can put in $24,500 as an employee deferral plus up to 25% of compensation as an employer contribution — up to the $72,000 combined cap.

How the 25% Calculation Actually Works for Self-Employed

This is where most freelancers get tripped up. When you’re self-employed, your “compensation” for retirement plan purposes is not your gross revenue. It’s your net earnings from self-employment after deducting half of your self-employment tax and the retirement contribution itself. This circular calculation effectively reduces the 25% employer contribution to roughly 20% of your net Schedule C income.

Here’s a simplified example. Say your Schedule C net profit is $100,000:

• Half of SE tax: approximately $7,065
• Net earnings for retirement purposes: approximately $92,935
• SEP IRA employer contribution (20% of net earnings): approximately $18,587

With a Solo 401(k), you can contribute the same $18,587 as an employer contribution plus $24,500 as an employee deferral — for a total of $43,087. That’s more than double what you could put into a SEP IRA at the same income level.

As the table shows, the Solo 401(k) advantage is most dramatic at lower and middle income levels. At $50,000 of net profit, you can contribute nearly $34,000 with a Solo 401(k) versus only about $9,300 with a SEP IRA. That extra $24,500 in pre-tax contributions could save you $5,000–$7,000 in taxes depending on your bracket.

Solo 401(k) Advantages Beyond Contribution Limits

The Solo 401(k) offers several features that the SEP IRA simply cannot match:

Roth Contributions

Many Solo 401(k) plans offer a designated Roth account. You can split your employee deferral between pre-tax and Roth, or direct the entire $24,500 to Roth. This is valuable if you expect to be in a higher tax bracket in retirement or want tax-free income later in life. SEP IRAs only accept pre-tax employer contributions — there’s no Roth option.

Plan Loans

Solo 401(k) plans allow you to borrow up to 50% of your account balance (up to $50,000) and repay it with interest over five years. This can be a lifeline for freelancers who need short-term liquidity without triggering taxes and penalties. SEP IRAs do not offer loan provisions — any withdrawal is a taxable distribution.

Higher Effective Contribution at Lower Income

As demonstrated above, the employee deferral component means you can reach meaningful contribution levels even with modest profits. A freelancer earning $30,000 can put away nearly $25,000 with a Solo 401(k) — effectively shielding most of their income from taxes. With a SEP IRA, the same freelancer could only contribute about $5,600.

Catch-Up Contributions

Because the Solo 401(k) has an employee component, you can make catch-up contributions starting at age 50. The 2026 catch-up is $8,000 for ages 50–59 and $11,250 for ages 60–63. This pushes the total Solo 401(k) limit to $80,000 (age 50–59) or $83,250 (age 60–63). SEP IRAs do not allow catch-up contributions — the $72,000 cap is the cap, regardless of age.

SECURE 2.0 Roth Catch-Up for High Earners

Starting in 2026, employees earning more than $150,000 in FICA wages in the prior year must make their catch-up contributions on a Roth basis. This applies to Solo 401(k) plans but not to SEP IRAs (which have no employee component and therefore no catch-up).

SEP IRA Advantages: Simplicity and Flexibility

Despite the Solo 401(k)’s higher contribution potential, the SEP IRA remains the better choice for many freelancers. Here’s why:

Minimal Paperwork

A SEP IRA can be opened in 15 minutes at any major brokerage (Fidelity, Vanguard, Schwab). You fill out Form 5305-SEP, and that’s it — no separate plan document, no annual filings. A Solo 401(k) requires adopting a formal plan document and, once the account balance exceeds $250,000, filing Form 5500-EZ annually with the IRS.

No Employee Deferral Restrictions

If you have employees, a Solo 401(k) requires you to offer the plan to all eligible employees and potentially make employer contributions on their behalf. A SEP IRA also requires contributions for eligible employees, but the administrative simplicity makes it easier to manage. For solopreneurs with no employees (or only a spouse), this is less of a concern.

Flexible Contribution Timing

With a SEP IRA, you can decide each year whether to contribute and how much — anywhere from 0% to 25% of compensation. In a bad year, you contribute nothing. In a great year, you max it out. The Solo 401(k) offers similar flexibility for the employer portion, but the employee deferral must be made through payroll deferral during the calendar year (though you can make the employer contribution up to the tax filing deadline).

Easy to Establish Late

You can open and fund a SEP IRA up to the tax filing deadline (including extensions, by October 15) and still deduct the contribution for the prior tax year. A Solo 401(k) must be established by December 31 of the tax year, though employer contributions can be made up to the filing deadline. If you’re doing year-end tax planning in March and realize you need more deductions, only the SEP IRA can save you.

The Decision Framework: Which Plan Is Right for You

Here’s a practical decision tree based on your net self-employment income:

Additional factors that might tip the scale:

• You have employees: Both plans require contributions for eligible employees, but the SEP is simpler to administer.
• You’re over 50: The Solo 401(k) catch-up adds $8,000–$11,250 of extra tax-deferred space. The SEP offers no catch-up.
• You want Roth savings: Only the Solo 401(k) offers a Roth option.
• You need a loan: Only the Solo 401(k) allows plan loans.
• You’re establishing the plan after year-end: Only the SEP IRA can be opened and funded after December 31 for the prior tax year.
• You value simplicity above all: The SEP IRA wins. No Form 5500, no plan document, no payroll setup.

Can You Have Both?

Yes — with caveats. You can maintain both a SEP IRA and a Solo 401(k), but the total employer contribution across all plans is capped at 25% of your compensation, and the total annual additions across all defined contribution plans cannot exceed $72,000 (or $80,000 with catch-up). The employee deferral limit of $24,500 is shared across all 401(k) plans — you can’t defer $24,500 into a workplace 401(k) and another $24,500 into a Solo 401(k).

For freelancers with no other 401(k) access, the Solo 401(k) alone almost always provides the maximum benefit. Having both plans is primarily useful if you have a W-2 job with a 401(k) and want to make additional employer contributions through a SEP IRA for your self-employment income.

Common Mistakes to Avoid

1. Choosing SEP IRA by Default Without Running the Numbers

Many freelancers open a SEP IRA because it’s the plan their bank or brokerage recommends by default. They never realize that a Solo 401(k) could let them contribute $20,000+ more per year. Run the calculation for your specific income level before deciding.

2. Missing the Solo 401(k) Establishment Deadline

A Solo 401(k) plan must be established by December 31 of the tax year. You can still make employer contributions up to the tax filing deadline, but the plan document must exist before year-end. If you’re reading this in January and want to contribute for the prior year, you’re limited to a SEP IRA.

3. Not Filing Form 5500-EZ

Once your Solo 401(k) balance exceeds $250,000, you must file Form 5500-EZ annually. The penalty for failing to file is $250 per day, up to $150,000. Set a calendar reminder for July 31 (the filing deadline) to avoid this costly mistake.

4. Overlooking the Roth Option

Younger freelancers or those who expect significant income growth in retirement should seriously consider directing their employee deferral to Roth. The tax-free growth over decades can far exceed the value of the current-year deduction, especially if tax rates rise in the future.

5. Forgetting About the Self-Employed Health Insurance Deduction Interaction

Your retirement contributions reduce your net self-employment income, which in turn affects your self-employed health insurance deduction. Work through the calculations in the right order — or use tax software — to avoid overestimating your deduction.

For International Freelancers: Currency Considerations

Freelancers who work with international clients face an additional layer of complexity when funding retirement accounts. Your contributions must be in U.S. dollars, but your income may arrive in euros, pounds, or other currencies. Exchange rate fluctuations can make it difficult to predict exactly how much you’ll be able to contribute by year-end.

Using a multi-currency account like Wise lets you receive payments in your clients’ currencies, convert at the mid-market rate when favorable, and transfer the exact dollar amount needed for your retirement contribution. This gives you more control over the timing and amount of your contributions, especially when exchange rates are volatile.

Frequently Asked Questions

Can I contribute to a Solo 401(k) if I also have a W-2 job with a 401(k)?
Yes, but the $24,500 employee deferral limit is shared across all 401(k) plans. If you’ve already deferred $24,500 at your W-2 job, you can’t make additional employee deferrals to your Solo 401(k). However, you can still make employer profit-sharing contributions up to 25% of your self-employment income, up to the $72,000 total cap.

Can I open a Solo 401(k) if my spouse helps with the business?
Yes. If your spouse is a legitimate employee of your business, they can participate in the Solo 401(k) and make their own employee deferrals and receive employer contributions. This effectively doubles the household retirement savings capacity.

Is there an income limit for contributing to a SEP IRA or Solo 401(k)?
No. Unlike Roth IRAs, which have income phase-outs, both the SEP IRA and Solo 401(k) are available at any income level. The only limits are the percentage-of-compensation and dollar caps discussed above.

Can I roll over a SEP IRA into a Solo 401(k)?
Yes. You can roll SEP IRA funds into a Solo 401(k) if your plan accepts rollovers. This can be beneficial if you want access to features like plan loans or if you want to consolidate accounts. The rollover is tax-free.

The Bottom Line

For most freelancers earning less than $200,000 in net self-employment income, the Solo 401(k) is the clear winner. The employee deferral component allows you to contribute dramatically more at lower income levels, the Roth option provides tax diversification, and the loan provision adds a safety valve. The SEP IRA remains the right choice for high earners who have maxed out both options, for those who value extreme simplicity, and for anyone who needs to make a prior-year contribution after December 31. Whichever plan you choose, the most important step is starting — every year you delay funding your retirement account is a year of compounding growth you can never get back.