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Solo 401k Contribution Calculator
Calculate the maximum Solo 401k contribution for self-employed individuals. See employee and employer profit-sharing limits plus estimated tax savings.
2024 limit: $23,000 ($30,500 if 50+)
Max total Solo 401k contribution
$45,131
Employee (elective deferral) portion
$23,000
Employer (profit sharing) portion
$22,131
Estimated tax savings (32% bracket)
$14,442
How the math works
A Solo 401k lets self-employed individuals contribute both as employee (up to $23,000 / $30,500 if 50+) and employer (25% of net adjusted self-employment income). The 2024 combined cap is $69,000 ($76,500 if 50+).
Net adjusted income = net SE income minus half of self-employment tax. Consult a CPA for final contribution calculations before filing.
EveryCalc calculators are designed for fast, practical estimates with transparent inputs and no required account. We use plain formulas, visible assumptions, and related tools so visitors can check the result from more than one angle.
Results are informational only. For financial, tax, legal, medical, construction, or other high-impact decisions, verify the output against primary sources or a qualified professional.
Learn more about our review process on the EveryCalc methodology page.
How this calculator works
What this page estimates
This Solo 401k Contribution Calculator is built to give a quick, browser-based estimate for solo 401k contribution. Calculate the maximum Solo 401k contribution for self-employed individuals. See employee and employer profit-sharing limits plus estimated tax savings. The inputs stay on the page during normal use, and the result should be treated as an estimate for planning, comparison, or education rather than professional advice.
Calculation approach
The calculator applies the standard relationship implied by the inputs, then formats the answer so it can be checked and reused. For finance tools, the most important step is using consistent units, rates, time periods, and assumptions before comparing the result with another calculator or outside quote.
Example workflow
For example, start with a realistic value you already know, change one input at a time, and watch how the answer moves. That makes it easier to tell whether the result is being driven by the main amount, the rate, the time period, or a unit conversion.
Practical checks
- Use current, real-world numbers when the result affects money, health, tax, or legal decisions.
- Run a low, base, and high case when the inputs are estimates.
- Check the related calculators below when the next decision depends on a different assumption.
How to interpret the solo 401k contribution result
Best use
Use the result as a planning number for comparing payments, rates, returns, tax reserves, or cash-flow choices before you request a quote or make a commitment.
Cross-check
Compare the answer with the contract, lender estimate, tax form, brokerage statement, payroll record, or invoice that will control the real-world outcome.
Watch for
Do not rely on a single optimistic rate, return, or fee assumption. Money pages work best when you run low, base, and high cases and keep professional advice separate from the estimate.
This page belongs to the Finance calculator library, so the answer should be read in the context of the decision you are modeling rather than as a universal rule.
Before relying on this solo 401k contribution estimate
Most calculator mistakes come from the inputs, not the arithmetic. Use this short audit before you reuse the answer in a spreadsheet, quote, application, or important conversation.
Confirm source numbers
Match balances, rates, fees, taxes, income, and payment dates against the lender quote, payroll record, tax form, statement, invoice, or contract.
Separate cash flow from total cost
A lower monthly payment can still cost more over time if fees, interest, taxes, or a longer term are hidden in the structure.
Run conservative cases
Test at least one higher-cost or lower-return case before using the output for a purchase, refinance, investment, loan, or tax decision.
Rerun this page when the rate, price, term, fee, tax rule, income, expense, or expected holding period changes.
How to Use
- Enter your net self-employment income for the year.
- Enter your age to see catch-up contribution eligibility.
- Enter your planned employee elective deferral contribution.
- See the max employer profit-sharing portion and total allowable contribution.
Frequently Asked Questions
Who can open a Solo 401k?
Any self-employed individual with no full-time employees (other than a spouse). This includes freelancers, consultants, sole proprietors, and single-member LLC owners.
What is the 2024 Solo 401k limit?
The total limit is $69,000 ($76,500 if age 50+). You can contribute up to $23,000 ($30,500 if 50+) as the employee, plus 25% of net adjusted SE income as the employer.
How is the employer contribution calculated?
The employer portion is 25% of your net adjusted self-employment income (after subtracting half of SE tax). This is the same rate as a SEP-IRA.
Solo 401k vs. SEP-IRA — which is better?
Solo 401k generally allows higher contributions at lower income levels because of the employee deferral. SEP-IRA is simpler to administer. Above ~$250k income, both hit similar limits.
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