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SEP IRA Calculator 2026

Free SEP IRA calculator for self-employed. Compute maximum contribution (20% of net self-employment earnings) and compare to Solo 401(k).

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Compute your maximum SEP IRA contribution as a self-employed sole proprietor. Up to 20% of adjusted net SE earnings, capped at $72,000 in 2026.

Maximum SEP IRA contribution

Federal tax savings

2026 IRS hard cap

$72,000

Your breakdown

Updates live as you type
StepAmount

Why a sole proprietor's rate is 20, not 25

A SEP IRA is the simplest serious retirement account a self-employed person can open. The headline rule is up to 25 percent of compensation, but the reduced contribution rate for a sole proprietor is generally 20 percent after the half-SE-tax adjustment. This tool runs that calculation and caps the result at the 2026 IRS limit of $72,000.

Sheltering $27,881 on $150,000 of profit

Walk through the defaults: $150,000 of net self-employment income at a 32 percent marginal rate. First, self-employment tax is $150,000 times 0.9235 times 0.153, which is $21,194; half of that, $10,597, is deductible and comes off the base. That leaves $139,403 of adjusted net earnings. Multiply by 20 percent and the maximum SEP contribution is $27,881, comfortably under the $72,000 ceiling. At a 32 percent marginal rate, contributing the full amount cuts your federal income tax by about $8,922.

The half-SE-tax step that lowers your base

That deduction for half of self-employment tax is not a quirk; it is the code treating you fairly. A regular employee splits Social Security and Medicare taxes with an employer, who pays half and deducts it as a business expense. A self-employed person pays both halves, so the law lets you deduct the employer-equivalent half as an adjustment to income. The SEP calculation respects that by computing your contribution base on earnings after that deduction. Skip the step and you would overstate both your contribution room and your deduction, which is a common error in back-of-envelope estimates.

SEP, Solo 401(k), and the same hard cap

Where a SEP stops being optimal is at moderate incomes. Because a SEP gives only the employer-style contribution, a sole proprietor often shelters more in a Solo 401(k), which adds an employee deferral. The SEP catches up only at high income, where both plans bump against the same $72,000 limit before catch-up and the simplicity of the SEP can win. The deadline and contribution mechanics are spelled out in IRS Publication 560.

Can I still contribute to a personal IRA if I have a SEP?

Yes. A SEP IRA is funded by the business and is separate from your personal traditional or Roth IRA, so you can contribute to both in the same year up to each one's own limit. Whether your personal traditional IRA contribution is deductible may be limited, however, because being covered by a SEP counts as being an active participant in a workplace plan for the IRA deduction phase-out.

What if my income varies wildly from year to year?

A SEP is well suited to lumpy income because the contribution is discretionary; there is no required annual amount. In a strong year you can fund the full 20 percent, and in a lean year you can contribute little or nothing without penalty. That flexibility is one reason freelancers and seasonal businesses favor it over plans with fixed funding commitments.

Frequently asked questions

SEP IRA vs Solo 401(k)?
A Solo 401(k) often allows more at moderate income because it adds a $24,500 employee deferral for 2026 to the employer contribution. A SEP IRA is simpler and may be attractive at high income where both plans reach the same $72,000 limit before catch-up.
How does 25% become 20% for a sole prop?
The 25% limit is "of compensation." For a sole proprietor, "compensation" means net SE earnings AFTER subtracting half the SE tax AND the SEP contribution itself. Solving the circular calculation gives an effective 20% of net SE earnings (before deduction).
Can I have both SEP and Solo 401(k)?
Potentially, but contributions sponsored by the same employer are coordinated under the $72,000 defined-contribution limit for 2026, before eligible 401(k) catch-up contributions. A business maintaining another qualified plan cannot use the basic Form 5305-SEP and may need a prototype or individually designed SEP document, so confirm the setup with the plan provider or a tax professional.
Can I have a SEP IRA and a solo 401(k) in the same year?
Potentially. The IRS does not impose a blanket one-plan-per-business rule, but plans maintained by the same employer share applicable annual-additions limits. Unrelated employers can have separate employer contribution limits, while your employee elective-deferral limit is generally shared across 401(k) and 403(b) plans. The interaction is easy to misapply, so coordinate contributions with both plan administrators.

Related calculators

Sources

  1. IRS Publication 560 — Retirement Plans for Small Business, Internal Revenue Service
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