01
Every limit, deadline, and eligibility rule in one audited ledger.
Last reviewed
Sources checkedIRS Publication 560, IRS Notice 2024-80
Figures move between tax years. Confirm the year you are filing before you set a contribution rate, because one stale number shifts the arithmetic for every account below.
2025 columns carry elective deferrals, employer contribution ceilings, and the compensation cap for Solo 401(k), SEP IRA, Traditional IRA, Roth IRA, and SIMPLE IRA. Plan establishment dates for 2025 have passed; funding deadlines for a plan already in place still apply.
2026 columns track the figures most readers use for the year ahead, with the same row and column order as 2025 so a year-over-year read stays honest. Where a limit is not yet finalized, the cell shows a pending marker rather than a number.
Matrix / tax year 2025
The full audited table: five account types across ten criteria, expanded to include withdrawal treatment and plan loans. Column order is identical wherever this matrix appears.
| Criterion | Solo 401(k) | SEP IRA | Traditional IRA | Roth IRA | SIMPLE IRA |
|---|---|---|---|---|---|
| Employee deferral1 | $23,500 | None | $7,000 | $7,000 | $16,500 |
| Catch-up, age 50+ | $7,500 | None | $1,000 | $1,000 | $3,500 |
| Employer side | Up to 25% of pay, $70,000 total cap | Up to 25%, same percentage for every participant | None | None | 3% match or 2% nonelective |
| Deductible this year | Yes, deferrals and employer side | Yes, employer side | Phases out if plan-covered | No | Yes |
| Withdrawal treatment | Ordinary income | Ordinary income | Ordinary income, 10% before 59½ | Tax-free if qualified | Ordinary income, 25% penalty first two years |
| Required distributions | Age 73, Roth sub-account exempt | Age 73 | Age 73 | None for the owner | Age 73 |
| Plan loans | Up to 50% vested, $50,000 max | Not permitted | Not permitted | Not permitted | Not permitted |
| Roth option | Designated Roth sub-account | Few custodians offer it | No | This is the Roth account | Only where the provider supports it |
| Setup deadline2 | Plan by Dec 31, deferrals by filing deadline | Filing deadline, extensions included | Filing deadline | Filing deadline | Oct 1 for a new plan |
| Best for | Owner-only, high profit | Least admin, variable profit | Small steady contributions | Tax-free growth, no owner RMD | Firms with roughly five employees |
Criterion-by-criterion notes and the full source list sit in criterion notes and sources.
04 / Sources
Every figure in the master matrix carries a marker. Each marker resolves to a notice, a publication, or a form listed here.
Contribution limits shown in the master matrix are 2025 tax-year figures1. Establishment deadlines and the self-employed deduction worksheet come from the small-business plan rules2. Traditional and Roth IRA contribution limits, including the compensation cap3, sit alongside distribution rules and required beginning dates4. The taxable portion of a withdrawal follows the annuity and pension rules5. SEP employers must apply a uniform contribution percentage to every eligible employee6. Annual Form 5500-EZ filing begins once plan assets cross the filing threshold7, and the saver's credit uses its own income tiers8.
IRS Notice 2024-80
Cost-of-living adjustments for tax year 2025: elective deferral limit, IRA limit, and catch-up amounts.
IRS Publication 560, Retirement Plans for Small Business
SEP, SIMPLE, and qualified plan rules, including plan establishment deadlines and the deduction worksheet for self-employed filers.
IRS Publication 590-A, Contributions to Individual Retirement Arrangements
IRA contribution limits, the taxable compensation requirement, and conversion mechanics.
IRS Publication 590-B, Distributions from Individual Retirement Arrangements
Qualified distributions, required beginning dates, and the penalty exceptions that apply before age 59 1/2.
IRS Publication 575, Pension and Annuity Income
How employer contributions and earnings are taxed when they leave the account.
IRS Form 5305-SEP
Model SEP agreement and the uniform percentage requirement for contributions across eligible employees.
Instructions for IRS Form 5500-EZ
Annual return filing for one-participant plans and the asset threshold that triggers it.
IRS Form 8880, Credit for Qualified Retirement Savings Contributions
Income tiers and phase-out ranges used for the saver's credit, which adjust separately from contribution limits.
When a contribution limit, threshold, or filing date in the master matrix changes, one short email records what moved and which source line changed. Nothing else.
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