Why the Solo 401k Beats Every Other Freelance Plan
The Solo 401k is the highest-limit retirement account available to a self-employed worker with no full-time employees, and the reason comes down to one feature: you contribute as both the employee and the employer. For 2026, that dual role produces a combined limit of $69,000 — $23,000 on the employee side plus up to 25% of compensation on the employer side. Cross age 50 and a $7,500 catch-up pushes the ceiling to $76,500.
I set up Solo 401ks for freelancers more than any other plan because no other account lets a single person shelter this much pre-tax income in a single year. A SEP IRA at the same income often allows half as much, especially below $200,000 of profit.
The Two Buckets for 2026
A Solo 401k has two contribution buckets, each with its own rule:
- Employee elective deferral: up to $23,000 in 2026, or $30,500 if you are 50+ with the $7,500 catch-up. This is a flat dollar cap, not a percentage. You can defer the full $23,000 even if your net self-employment income is only $23,000.
- Employer profit-sharing: up to 25% of your compensation. For a sole proprietor, "compensation" means net Schedule C profit minus half of self-employment tax, then minus the contribution itself — which works out to roughly 20% of adjusted net earnings.
The two buckets stack, but the combined total cannot exceed the Section 415(c) cap of $69,000 for 2026 ($76,500 with catch-up).
The Math at Three Income Levels
How much you can actually contribute depends on profit. Here is what I see in practice for sole proprietors under 50 in 2026:
| Net SE Profit | Employee Deferral | Employer (≈20%) | Total |
|---|---|---|---|
| $80,000 | $23,000 | $14,000 | $37,000 |
| $150,000 | $23,000 | $26,500 | $49,500 |
| $300,000 | $23,000 | $46,000 | $69,000 (capped) |
A freelancer earning $80,000 tops out near $37,000. At $150,000, the number climbs to roughly $49,500 — a federal tax savings of about $11,900 at the 24% bracket. You only hit the full $69,000 ceiling once net profit approaches $300,000, because the employer side needs enough compensation to absorb the remaining $46,000. Run your own numbers with the Self-Employment Tax Calculator before deciding how much to defer.
Traditional vs Roth Inside the Plan
Most modern plan providers — Fidelity, Schwab, E*TRADE, and Vanguard — offer a Roth option inside the Solo 401k. The employee deferral can be split between pre-tax and Roth in any proportion. The employer profit-sharing side is always pre-tax. For freelancers in their peak earning years, I usually recommend pre-tax deferrals to drive down current taxable income; for younger owners or lower-income years, Roth makes more sense because the tax is paid at a low bracket now and withdrawals are tax-free later.
Two Deadlines That Trip People Up
The employee deferral must be made by December 31, 2026 — you cannot backfill it in January. The employer profit-sharing contribution can be funded any time up to your tax filing deadline, including extensions (October 15, 2027 for a sole proprietor who extends). Critically, the plan itself must be established by December 31, 2026 to make any 2026 employee deferrals, even though the employer money can wait until the following October.
The Bottom Line
The 2026 Solo 401k lets a self-employed worker contribute up to $69,000 ($76,500 at 50+), split between a $23,000 employee deferral and up to 25% of compensation as employer profit-sharing. At $150,000 of profit you can typically shelter around $49,500. Establish the plan by December 31, 2026 to lock in the employee deferral; fund the employer side by your filing deadline. Use the Self-Employment Tax Calculator to model the SE-tax picture and the Tax Deduction Finder to confirm the deduction lands in the right place on your return.