Finance

Small Business Retirement Plan Options: SEP-IRA, SIMPLE IRA, Solo 401(k) (2026)

Small business owners are on their own when it comes to retirement. There's no company matching your 401(k) contributions — you are the company. That means the responsibility for building retirement security falls entirely on you, and the right plan choice can save you tens of thousands of dollars in taxes while building serious wealth over time.

Why This Decision Matters More Than You Think

The difference between having a retirement plan and not having one isn't just about your future security. Retirement contributions reduce your taxable income dollar-for-dollar today. If you're in a 25% combined federal and state tax bracket, every $10,000 you contribute to a retirement plan saves you $2,500 in taxes this year. A plan with a $60,000 annual contribution limit saves you $15,000 in taxes — annually — compared to taking the same money as taxable income.

The goal is to find the plan that allows the maximum contribution for your situation, at the minimum administrative cost.

The Four Main Options for Small Business Owners

SEP-IRA (Simplified Employee Pension)

The SEP-IRA is the simplest plan to set up and is ideal for self-employed individuals and small business owners without employees. You can open one at any brokerage (Fidelity, Vanguard, Schwab) in about 15 minutes, with no annual paperwork requirements.

2026 contribution limits: Up to 25% of net self-employment income, or $70,000 — whichever is less. For a business owner earning $200,000 in net profit, that's potentially a $50,000 deduction.

The catch for businesses with employees: If you have employees, you must contribute the same percentage of their compensation that you contribute for yourself. If you contribute 20% for yourself, you must contribute 20% of every eligible employee's salary as well. This makes the SEP-IRA expensive as a business grows its headcount.

Best for: Solo business owners or partnerships with no employees, who want simplicity and high contribution limits.

Solo 401(k) (also called Individual 401(k))

The Solo 401(k) is the most powerful retirement tool available to self-employed business owners — but it only works if you have zero employees (other than a spouse). It allows you to contribute as both the "employee" and the "employer," stacking two contribution types for a higher total than a SEP-IRA at most income levels.

2026 contribution limits: Employee deferral: up to $23,500 (plus $7,500 catch-up if you're 50+). Employer contribution: up to 25% of net self-employment income. Total combined limit: $70,000. At lower income levels, the Solo 401(k) beats the SEP-IRA because the employee deferral component isn't income-limited the same way.

Roth option: Many Solo 401(k) providers allow Roth contributions on the employee deferral portion — tax-free growth and tax-free withdrawals in retirement, with no income limits that apply to regular Roth IRAs. This is a significant benefit that SEP-IRAs don't offer.

Best for: Self-employed owners with no employees who want maximum contribution flexibility, especially at lower income levels or if a Roth option is a priority.

SIMPLE IRA

The SIMPLE IRA is designed for small businesses with up to 100 employees. It's easier and cheaper to administer than a traditional 401(k), and it requires employer contributions — either matching employee contributions up to 3% of compensation, or a flat 2% for all eligible employees regardless of whether they contribute.

2026 contribution limits: Employees can defer up to $16,500 (plus $3,500 catch-up if 50+). The employer match or non-elective contribution is on top of that.

Trade-offs: Lower employee deferral limits than a 401(k), and mandatory employer contributions mean you're always putting money in for employees whether or not the business is having a good year. Once you set up a SIMPLE IRA, you must maintain it for two years before switching to a different plan type.

Best for: Businesses with 5–50 employees that want a retirement benefit to attract and retain staff without the administrative complexity of a full 401(k).

Traditional 401(k) Plan

A full 401(k) plan offers the highest contribution limits and maximum flexibility, but comes with annual compliance testing, Form 5500 filing, and plan document requirements that typically require a third-party administrator (TPA). Costs run $1,500–$5,000+ per year in administrative fees.

This makes sense once you have enough employees that the economies of scale justify the administration cost, typically 20+ employees or when you want features like profit-sharing, loans, or matching that go beyond what simpler plans offer.

Best for: Growing businesses with 20+ employees or businesses that want robust profit-sharing features and can absorb the administrative overhead.

The Decision Framework

• No employees, want simplicity, higher income? → SEP-IRA
• No employees, want maximum contributions at all income levels, or want Roth? → Solo 401(k)
• Have 1–20 employees, want a benefit that's easy to manage? → SIMPLE IRA
• Growing team of 20+, need full features? → Traditional 401(k)

Open any of these plans at Fidelity, Vanguard, or Schwab — all three offer these plan types with no setup fees and no annual maintenance fees for the basic versions. The difference is in the investment options and the interface. All three are excellent.

Consult a CPA before finalizing your choice. The tax savings are significant enough that a one-hour consultation pays for itself many times over. This guide gives you the vocabulary and framework — a professional gives you the final number for your specific situation.