Can 1099 Contractors Open a Solo 401(k)? Yes. Here Is the $52,000 Example
A contractor nets $150,000 in 1099 income and asks the obvious question: can 1099 contractors open a solo 401(k)? Yes. The IRS calls it a one-participant 401(k), and 1099-NEC income from work you personally perform qualifies you to open one. The number that matters is what it lets you shelter: at $150,000 of net self-employment income, a solo 401(k) holds about $52,000 for the year. A SEP IRA on the same income holds about $28,000. The rest of this piece is why.
The two-hat trick
A solo 401(k) lets you contribute in two roles. Wearing the employee hat, you defer up to $24,500 for 2026. Wearing the employer hat, you add up to 25% of compensation, which works out to roughly 20% of net self-employment income for a sole proprietor after subtracting half your self-employment tax. The two pieces stack inside a combined $72,000 annual limit.
Here is the $150,000 example. Net profit of $150,000 minus half the self-employment tax, about $10,596, leaves a contribution base of $139,404. The employer piece is roughly 20% of that, about $27,881. Add the $24,500 employee deferral and the total is $52,381. A SEP IRA only gets the employer piece, the $27,881. The employee deferral is the entire difference, and at 50+ it grows: an $8,000 catch-up, or $11,250 if you are 60 to 63, takes the combined ceiling to $80,000 or $83,250.
The two rules that decide whether 1099 contractors can open a solo 401(k)
First, the income has to be earned income from your business. For a sole proprietor that means Schedule C net profit. Interest on a 1099-INT, dividends on a 1099-DIV, and retirement distributions on a 1099-R do not count, so you cannot open a solo 401(k) just to consolidate old IRAs.
Second, your business cannot have full-time employees other than you and your spouse. The IRS draws the line at common-law employees working more than 1,000 hours a year. Occasional subcontractors do not disqualify you. One full-time hire does, and the plan has to become a regular 401(k) at that point.
One more advantage the SEP cannot touch
The solo 401(k) can hold a designated Roth account, with no income limits. A contractor earning too much for a direct Roth IRA can still make Roth deferrals inside the solo 401(k). A SEP IRA has no Roth option at all. For a high-earning contractor in a low-income year, or one who simply expects higher brackets in retirement, that is a real planning lever the SEP does not offer.
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Compare 1099 vs W-2 freeFrequently asked questions
Can 1099 contractors open a solo 401(k)?
Yes. 1099-NEC income from services you personally perform is self-employment income, which qualifies you to open a solo 401(k), provided your business has no full-time employees other than you and your spouse.
How much can a 1099 contractor contribute to a solo 401(k) in 2026?
Up to $24,500 in employee deferrals plus an employer contribution of roughly 20% of net adjusted self-employment income, within a $72,000 combined limit ($80,000 at 50+, $83,250 at 60 to 63).
Does 1099-INT or 1099-DIV income qualify for a solo 401(k)?
No. Only earned income qualifies. Interest, dividends, and retirement distributions are passive income and cannot support solo 401(k) contributions.
Is a solo 401(k) better than a SEP IRA for a 1099 contractor?
Usually, yes, because of the employee deferral: at $150,000 of net income the solo 401(k) shelters about $52,000 versus the SEP IRA's $28,000. The SEP is simpler to administer, so it wins only when you value simplicity over the extra contribution room.
Related: The Self-Employment Tax Rate for 1099 Workers · 1099 vs W-2 Retirement Savings Compared · The Estimated Tax Safe Harbor Rule for 1099 Contractors · Should a 1099 Contractor Form an LLC?
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