CalcSumly

California (CA) Self-Employed Retirement Contribution Calculator

Tax year: 2026 · Figures for Tax Year 2026 · Source: IRS

Built and audited by the CalcSumly Engineering Team using official IRS and State Department of Revenue data.

Your Schedule C net profit before the retirement contribution deduction.

$

Age as of December 31. Determines your Solo 401(k) catch-up contribution tier (ages 50+, 60-63).

yrs

Solo 401(k)

Recommended

$46,804

maximum contribution · 2026

Employee deferral$24,500
Employer profit-sharing$22,304
Federal income tax saved (22.0% marginal)$10,119
State income tax saved$4,175
Total tax savings$14,293

SEP-IRA

$22,304

maximum contribution · 2026

Employer profit-sharing$22,304
Federal income tax saved (22.0% marginal)$4,907
State income tax saved$2,074
Total tax savings$6,981

At $120,000 of self-employment income in California, a Solo 401(k) allows $46,804 maximum contribution versus $22,304 for a SEP-IRA — a difference of $24,500 in contribution capacity.

How self-employed retirement contributions work in California for 2026

Solo 401(k) and SEP-IRA contributions are above-the-line deductions on Form 1040 Schedule 1. They reduce federal AGI but do not affect self-employment tax (SE tax is calculated on Schedule C net profit before contributions).

California taxes federal AGI minus the California standard deduction. Retirement contributions reduce federal AGI and therefore reduce California taxable income at your marginal California rate.

Solo 401(k) vs SEP-IRA comparison

The Solo 401(k) allows a larger contribution at most income levels because it adds an employee elective deferral ($24,500) before the employer profit-sharing portion. The SEP-IRA has only the employer portion (20% of net SE compensation, capped at $72,000). At very high incomes where the Solo 401(k) base also hits $72,000, the plans become equal unless you qualify for a catch-up contribution (Solo 401(k) only).

Catch-up contributions (Solo 401(k) only)

Filers age 50-59 or 64+ add $8,000 in catch-up above the §415(c) cap. Filers age 60-63 add $11,250 (SECURE 2.0 enhanced catch-up). SEP-IRA has no catch-up at any age.

Scope and limitations

This calculator models standard deduction filers. It does not include QBI deduction, health insurance deduction, other plan types, or interactions with employer 401(k) plans from W-2 employment. Consult a tax professional and plan custodian before contributing.

Sources

Frequently asked questions

Do retirement contributions reduce self-employment tax?+

No. Solo 401(k) and SEP-IRA contributions are above-the-line deductions on Form 1040 Schedule 1, not Schedule C deductions. SE tax is calculated on Schedule C net profit before contributions. Contributions reduce federal AGI, which lowers federal income tax and most state income taxes, but SE tax is unchanged.

What is the maximum Solo 401(k) contribution for self-employed in 2026?+

The 2026 Solo 401(k) base maximum is $72,000 (§415(c)) plus catch-up: $8,000 for ages 50-59 or 64+ and $11,250 for ages 60-63 (SECURE 2.0). The employee elective deferral is $24,500. The employer portion is 20% of net SE compensation (IRS Pub 560 formula). The elective deferral plus employer contribution cannot exceed $72,000.

What is the maximum SEP-IRA contribution for 2026?+

The 2026 SEP-IRA maximum is 20% of net SE compensation (net profit minus the deductible half of SE tax), capped at $72,000. Net SE compensation is also capped at the §401(a)(17) compensation limit of $360,000. SEP-IRA has no employee deferral and no catch-up option.

Do California state taxes recognize Solo 401(k) and SEP-IRA deductions?+

Yes. California conforms to the federal treatment of self-employed retirement plan deductions. Contributions to a Solo 401(k) or SEP-IRA reduce federal AGI, which reduces California taxable income (federal AGI minus the California standard deduction of $5,706 single / $11,412 MFJ for 2026). California rates range from 1% to 12.3% plus a 1% Mental Health Services surtax above $1,000,000.

How much state tax does a Solo 401(k) save in California?+

The state tax savings depend on your California marginal rate. For most self-employed filers earning $60,000 to $120,000, the marginal California rate is 9.3%. A $46,000 Solo 401(k) contribution would save roughly $4,300 in California income tax on top of the federal savings. Exact amounts depend on your income level and the specific contribution.

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