Self Employed 401k Calculator

Solo 401k Contribution Calculator

Your Max Contribution Summary

Employee Elective Deferral: $0

Employer Profit Sharing: $0

Catch-up Contribution (Age 50+): $0

Total Maximum Contribution: $0

function calculateSolo401k() { var year = document.getElementById('taxYear').value; var entityType = document.getElementById('entityType').value; var income = parseFloat(document.getElementById('annualIncome').value); var age = parseInt(document.getElementById('userAge').value); if (isNaN(income) || income currentLimits.total) { profitSharing = currentLimits.total – empDeferral; } } else { // For Corporations (S-Corp/C-Corp), it is based on W-2 Salary empDeferral = Math.min(income, currentLimits.deferral); profitSharing = income * 0.25; if ((empDeferral + profitSharing) > currentLimits.total) { profitSharing = currentLimits.total – empDeferral; } } if (age >= 50) { catchUp = currentLimits.catchup; } var total = empDeferral + profitSharing + catchUp; document.getElementById('employeeDeferral').innerText = "$" + empDeferral.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('employerContribution').innerText = "$" + profitSharing.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('catchUpAmount').innerText = "$" + catchUp.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('totalContribution').innerText = "$" + total.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2}); document.getElementById('resultsDisplay').style.display = 'block'; }

Understanding the Solo 401k Contribution Limits

A Solo 401k, also known as an Individual 401k or One-Participant 401k, is a powerful retirement savings vehicle designed specifically for business owners with no full-time employees other than themselves and their spouse. It offers higher contribution limits than almost any other retirement plan available to the self-employed.

How Contributions are Calculated

The Solo 401k allows you to contribute in two distinct capacities:

• The Employee (Elective Deferrals): You can contribute 100% of your earned income up to the annual limit. For 2024, this limit is $23,000. If you are 50 or older, you can add a "catch-up" contribution of $7,500.
• The Employer (Non-elective Contributions): Your business can contribute an additional amount based on a percentage of your income. For S-Corps, this is 25% of your W-2 wages. For Sole Proprietors, this is roughly 20% of your net adjusted self-employment income.

Solo 401k Limits for 2023 vs. 2024

Feature	2023 Limit	2024 Limit
Employee Deferral	$22,500	$23,000
Total Plan Limit	$66,000	$69,000
Catch-up (Age 50+)	$7,500	$7,500

Example Scenarios

Example 1: The High-Earning Consultant (S-Corp)
Sarah is 45 years old and operates as an S-Corp. She pays herself a W-2 salary of $100,000. In 2024, she can contribute $23,000 as an employee and $25,000 (25% of $100k) as the employer, for a total of $48,000.

Example 2: The Sole Proprietor Close to Retirement
Mark is 55 years old and a freelance writer (Sole Prop). His net business profit is $80,000. After adjusting for self-employment tax, his total allowed contribution would include the $23,000 employee deferral, the $7,500 catch-up, plus his 20% employer contribution, significantly reducing his taxable income.

Critical Deadlines

To make contributions for a specific tax year, the Solo 401k plan must generally be established by December 31st of that year. However, thanks to the SECURE Act, you now have until your tax filing deadline (including extensions) to establish and fund the employer portion of the plan. Employee deferrals usually need to be "elected" by year-end for most business types.