Solo 401(k) Contribution Tax Deduction Calculator & Eligibility
Solo 401(k) Contribution is a above-the-line tax deduction for 2026 with up to $69,000. Confirm eligibility, keep the required records, and use Form 5500-EZ when claiming it.
Quick Answer
Solo 401(k) Contribution is a above-the-line tax deduction for 2026 with up to $69,000. Confirm eligibility, keep the required records, and use Form 5500-EZ when claiming it.
Use this page to estimate federal savings, compare tax brackets, check required forms, and avoid common filing mistakes before you claim it.
Eligibility
Self-employed with no employees (except spouse)
Tax Savings Calculator
Estimated Tax Savings
$1,100
At the 22% tax bracket, a $5,000 deduction saves you $1,100 in taxes.
Savings by Tax Bracket
Requirements
- 1$23K employee + 25% employer
- 2$69K total max
- 3No other employees
Common Mistakes to Avoid
- !Having non-spouse employees
- !Not considering Roth option
IRS Source Check & Audit File
Primary source: IRS Forms, Instructions, and Publications. Federal tax deductions and credits depend on the current-year form instructions, eligibility rules, and taxpayer-specific facts.
Keep the source document and records with the return for the year claimed. If your facts involve business entities, foreign accounts, disaster losses, or retirement conversions, have a CPA or Enrolled Agent review the filing position before submitting.
Methodology & Official Sources for Solo 401(k) Contribution
How the Solo 401(k) Contribution works: This federal tax deduction can reduce taxable income before tax brackets are applied when the taxpayer meets the current-year eligibility rules. The exact savings depend on your marginal tax rate, filing status, income, and documentation. Eligibility, limits, and phaseout thresholds are governed by the Internal Revenue Code and updated through IRS forms, instructions, publications, notices, and revenue procedures.
Authoritative sources:
- IRS Publications — official deduction guides
- IRS Forms & Instructions — current year tax forms
- Internal Revenue Code — primary tax law authority
- IRS Interactive Tax Assistant — eligibility self-check
- Taxpayer Advocate Service — IRS dispute resolution
- IRS Free File — free tax filing for eligible taxpayers
Tax Disclaimer: Tax law is complex and changes annually. The information shown reflects current 2026 IRS guidance. For your specific situation — especially if you have business income, foreign accounts, or unusual deductions — consult a licensed CPA, Enrolled Agent (EA), or tax attorney. Errors in deduction claims can trigger audits.
Reviewed by Brazora Monk · Last updated 2026
Required Tax Forms
Calculate Your Full Tax Savings
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2. Review assumptions
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Planning estimate, not tax advice
LevyIO calculators are educational planning tools. Actual federal, state, payroll, property, sales, and local tax results can change with filing status, credits, deductions, residency, employer withholding, address-level rates, and current forms. Verify final filing positions with IRS or state guidance, payroll records, tax software, or a qualified tax professional.
Frequently Asked Questions
What is the Solo 401(k) Contribution?
Self-employed can contribute as both employee and employer to Solo 401(k).
Who is eligible for the Solo 401(k) Contribution?
Self-employed with no employees (except spouse)
How much can I save with the Solo 401(k) Contribution?
The average tax savings is $18,000 per year. The maximum deduction is $69,000. Your actual savings depend on your tax bracket and qualifying amount.
What forms do I need for the Solo 401(k) Contribution?
You'll need to file Form 5500-EZ to claim this deduction.
What are common mistakes with the Solo 401(k) Contribution?
Common mistakes include: Having non-spouse employees; Not considering Roth option. Always double-check requirements before filing.
Is the Solo 401(k) Contribution worth claiming?
With average savings of $18,000, the solo 401(k) contribution is highly valuable. Make sure you meet all eligibility requirements.