Start from Schedule C profit, then make the SE-tax adjustment
Enter supported Schedule C net profit, not gross platform payouts. The calculator subtracts the deductible half of regular self-employment tax before applying the reduced employer contribution rate; it does not multiply Schedule C profit directly by 25%.
If you already have W-2 Social Security wages, enter them because the shared wage base can change the deductible SE-tax half and therefore plan compensation. Use /schedule-c-tax-calculator/ to inspect the receipt-to-profit bridge first.
SEP and one-participant 401(k) are alternatives
The 2026 data version records the SEP employer limit, the $24,500 elective-deferral limit, the $8,000 standard catch-up, and the higher $11,250 catch-up scenario for ages 60–63. Existing deferrals and another employer plan can reduce room, and a low profit can cap the total below a published limit.
Read /guides/driver-retirement/ before opening or changing a plan.
A scenario is not plan administration
The W-2 + 1099 calculator can show how withholding and profit affect cash planning. This page does not prepare plan documents or determine final eligibility.
Frequently asked questions
Can I add the SEP and Solo 401(k) maximums?
No. They are alternative scenarios here; the limits must not be summed.
Does this open a retirement account?
No. It only compares an estimate from entered profit and known limits.
Why is the result below the published maximum?
Self-employed compensation, the reduced rate, existing deferrals, age, and other plan use can limit the scenario.
Official sources
- IRS 2026 inflation adjustments (Rev. Proc. 2025-32)
- IRS Topic 554: Self-employment tax
- IRS 2026 retirement limits and self-employed contribution guidance
- IRS 2026 SEP contribution limits
- IRS one-participant 401(k) contribution rules
See methodology for formulas, source status, assumptions, and known limits.