401(k) Calculator

Go Beyond a SEP IRA: See What a Solo 401(k) Can Really Do

Know exactly how much you can put away in your Solo 401(k) for 2025 as both the “employee” and the “employer” — using simple inputs and clear, visual results. Perfect for owner-operators with no common-law employees.

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Travis Tandy CEO & President of Tandy Consulting Inc

If you’ve only used a SEP IRA in the past, you might be leaving Solo 401(k) room on the table. This calculator lets you see how combining employee deferrals and employer profit sharing can boost your total retirement contributions for 2025.

  • See your maximum Solo 401(k) contributions in real dollars for 2025
  • Separate breakdown for employee deferral, employer profit sharing, and catch-up (age 50+)
  • Designed for owner-only businesses (sole props, single-member LLCs, and S-corps)
  • Helps you compare Solo 401(k) vs. SEP IRA potential at your income level
  • Built by Tandy Consulting for real-world tax and retirement planning conversations
S-Corp 401(k) Planning Guide + Calculator (2026) | Tandy Consulting Inc.

S-Corp 401(k) Planning Guide (2026)

A threshold-focused guide for S-corporation owners: W-2 wage targets, employee deferrals, employer match + profit-sharing, plus calculators you can use anytime during the year.

Tandy Consulting Inc.
Built for Guideline 401(k)

Key Limits & Planning Framework (2026)

Planning guardrail used in these calculators: Total contributions (employee + employer) are capped at $72,000.

2026 Employee Deferral Limits (401(k))

  • Under 50: $24,500
  • Age 50--59: $32,500
  • Age 60--63: $35,750
Employee deferrals are combined across jobs
Total cap used here: $72,000

Calculator-Style Sweet Spot Table (Reusable)

Table logic: max employee deferral first (up to $24,500), then employer funding is added, capped at $72,000 total (employee + employer).

W-2 Wages Employee Deferral (base) Employer Funding (up to 25%) Total (capped at $72,000)
Guideline alignment: This setup matches Guideline plan building blocks (employee deferrals, employer match, profit-sharing).
Educational info only. Plan rules and aggregation rules may vary.

Quick Calculator (2026) -- S-Corporation (W-2)

Advanced: include other job employer match/profit-sharing?
Use only if employer contributions must be aggregated (e.g., controlled group). Otherwise, employer contributions are typically per plan.
Max remaining profit-sharing for this company
Calculates how much additional profit-sharing you can still add (after match), limited by: (1) 25% of W-2 employer cap, and (2) the $72,000 total cap, after subtracting contributions already made.
Employee deferral room remaining (all jobs)
$0
Age-based limit minus all employee deferrals already made.
Additional employee deferral you can still do (this company)
$0
Subtracts this company's YTD deferrals too.
Additional employer funding you can still add (this company)
$0
Match: $0 • Profit-sharing: $0
Projected total at year-end (all known inputs)
$0
Includes YTD + planned amounts; capped at $72,000 in this tool.
Limits: --
Employer cap: 25% of W-2 (match + PS)
Enter YTD contributions and planned amounts, then click Calculate.

Quick Calculator (2026) -- Self-Employed (Sole Proprietor / Single-Member LLC)

Uses a planning approach: employer contribution is commonly 20% of net earnings, where net earnings ≈ Schedule C net profit − ½ SE tax. Add YTD contributions so this works mid-year.
Advanced: apply Social Security wage base cap (optional)
If you already have W-2 wages elsewhere, the Social Security portion of SE tax may be reduced. Turn on and enter the annual wage base and SS wages already used.
Estimated self-employment tax
$0
Planning estimate; depends on wage base + other facts.
Net earnings used (approx.)
$0
Net profit − ½ SE tax (planning).
Employee deferral room remaining (all jobs)
$0
Age-based limit minus all employee deferrals already made.
Additional employer contribution you can still add
$0
Accounts for employer already contributed YTD.
Additional employee deferral you can still do (self-employed plan)
$0
Subtracts self-employed plan employee deferrals already made.
Projected total at year-end (all known inputs)
$0
Includes YTD + remaining amounts; capped at $72,000 in this tool.
½ SE tax deduction
$0
Displayed for transparency.
Notes
--
See details below.
Enter YTD contributions and planned amounts, then click Calculate.

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