SIMPLE IRA vs. 401(k): Which One Actually Fits a 12-Person Business?

If you run a 12-person business, both a SIMPLE IRA and a 401(k) can provide employees with a valuable retirement benefit—but they work very differently.

A SIMPLE IRA generally offers easier administration and fewer compliance requirements. A 401(k) provides higher contribution limits and more flexibility, but usually requires more plan management.

So, which one fits your business better?

What a SIMPLE IRA actually is

SIMPLE stands for Savings Incentive Match Plan for Employees — a mouthful for something that's genuinely straightforward. Employees set aside a portion of their paycheck pre-tax, and the employer kicks in a contribution too, either as a match or a flat percentage.

No plan document drafted by a benefits attorney charging by the hour, and in most cases, no Form 5500 filing.

• Employer contributions to your SIMPLE IRA
• Easy payroll-based retirement savings
• Tax-advantaged retirement contributions

SIMPLE IRA vs. 401(k): a side-by-side look

The honest answer to "which one should I pick" usually comes down to size and budget. Here's how the two stack up for 2026:

That vesting row deserves its own beat. With a SIMPLE IRA, every dollar the employer puts in belongs to the employee immediately - no "stay three years to keep it." For a small business competing with bigger companies on benefits, that's a real selling point when recruiting, not just a compliance footnote.

Why a SIMPLE IRA may fit a 12-person business

Consider a small business with 12 employees and no dedicated benefits department.

The owner wants to provide a retirement plan but does not want to manage complicated testing, annual government filings, or extensive plan administration.

A SIMPLE IRA can work well in this situation.

There is generally no annual Form 5500 filing and no traditional 401(k)-style nondiscrimination testing.

The trade-off is that employer contributions are generally required.

So while the plan may be easier to administer, employers should consider the required contributions when comparing total costs.

Why a 401(k) may be worth the extra administration

A 401(k) becomes more attractive when owners or employees want to save more.

For 2026, an employee can generally contribute up to $24,500, before applicable catch-up contributions.

A 401(k) can also support features such as:

• Employer matching
• Profit-sharing contributions
• Roth contributions
• Participant loans
• Automatic enrollment
• Customized eligibility provisions
• Different employer contribution structures

The total amount contributed to a participant's defined contribution account can also be significantly higher than the employee deferral limit alone. For 2026, the general defined contribution limit is $72,000, excluding applicable catch-up contributions.

Which one fits your business?

A SIMPLE IRA may be a better fit if:

• You want simpler administration.
• You are comfortable making required employer contributions.
• Higher contribution limits are not a major priority.
• You do not need participant loans or extensive customization.

A 401(k) may be a better fit if:

• Owners or employees want higher contribution limits.
• You want more flexibility in plan design.
• You want features such as loans or profit sharing.
• You expect the business to grow.
• Retirement benefits are important for recruiting and retention.

The number of employees alone should not determine your choice.

For a 12-person business, the more important question is whether you value administrative simplicity or greater contribution capacity and flexibility.

The part that actually trips people up

Setting up a SIMPLE IRA isn't hard, but staying compliant with it is where small business owners quietly fall behind. Employees need written notice before the plan year starts, the correct IRS form has to be filed (5304-SIMPLE or 5305-SIMPLE, depending on whether employees choose their own provider), payroll deductions have to be calculated correctly every cycle, and contribution deposit deadlines are ones the IRS does not treat casually.

None of this is complicated in isolation. But it adds up, especially if you're already handling your own bookkeeping, your own payroll, and the actual business on top of it. This is exactly the gap WealthRabbit was built to close: notice deadlines, contribution calculations, and IRS paperwork tracked in one place instead of scattered across spreadsheets and sticky notes.

About the Author

Adam Ackerman, CFP®

Co-Founder & CCO at WealthRabbit

Adam Ackerman is a CFP® and President of BNA Wealth, where he built his practice around planning—not products. He brings that same planning-first mindset to WealthRabbit, helping small business owners and their advisors cut through the complexity of retirement decisions and focus on what actually matters: building a plan that works for their business, their people, and their own financial future.