Key takeaways

  • Small business owners and self-employed individuals have access to retirement plans that allow substantially higher annual contributions than standard employee plans. A SEP-IRA or Solo 401(k) can accept up to $72,000 in total annual contributions in 2026, far above what standard employee plans allow for employee deferrals alone.
  • The right plan depends on whether the business has employees, how much the owner earns, and whether flexibility or simplicity matters more in a given year. A solo operator has different priorities from a business owner with a team, and the plans available to each differ in structure and obligation.
  • Each plan type carries its own setup deadline, contribution formula, and employee coverage requirement. Choosing the wrong plan for the business structure can create compliance obligations that are difficult to undo.
  • Tax deductions for retirement contributions can reduce a small business owner’s taxable income substantially in high-revenue years. For someone in the 37 percent federal bracket, a maximum SEP-IRA contribution of $72,000 reduces the federal tax bill by $26,640 in the year it is made.

Why small business owners need a dedicated retirement plan

Employees at large companies are often automatically enrolled in employer-sponsored retirement plans. Their employer contributes to a matching structure, plan administration is handled by HR, and the enrollment decision is often passive. Small business owners and the self-employed do not have that infrastructure working in the background.

Why having no plan limits retirement savings

Without a formal retirement plan, every dollar of business profit is taxable income in the year it is earned. There is no mechanism to defer taxes on savings, no employer match to capture, and no tax-advantaged vehicle for business profits, aside from the standard IRA contribution limit of $7,500 per year (or $8,600 for those 50 and older).

The contribution gap

An owner who establishes a SEP-IRA or Solo 401(k) can contribute up to $72,000 in 2026, nearly ten times the standard IRA ceiling. Over ten years at a 7 percent annual return, the difference between contributing $7,500 and $72,000 per year compounds to approximately $940,000 in additional retirement savings.

How self-employment taxes affect contributions

Self-employed individuals pay both the employer and employee portions of Social Security and Medicare taxes, which together total 15.3 percent on net earnings up to the Social Security wage base. For sole proprietors, contributions to a SEP-IRA or Solo 401(k) are deducted on Schedule 1 of Form 1040, which reduces federal income tax but does not reduce the net earnings on Schedule C used to calculate that 15.3 percent. S-Corp owners who pay themselves a reasonable salary can reduce self-employment tax exposure through the salary-and-distribution structure, which is a separate planning consideration worth reviewing with a tax advisor.

Go Further: Traditional vs. Roth accounts: Tax advantages explained covers how the tax treatment of pre-tax and Roth contributions differs and why that choice has different implications depending on expected retirement income.

Retirement plan options for small business owners

The four primary plan types available to small business owners and the self-employed are the SEP-IRA, the SIMPLE IRA, the Solo 401(k), and the traditional or Roth IRA. Each has a distinct structure, contribution formula, and set of rules governing who must be covered when employees are involved.

SEP-IRA

A SEP-IRA (Simplified Employee Pension Individual Retirement Account) is an employer-funded retirement account that allows a business owner to contribute to their own retirement and to that of any eligible employees using a single, simple formula.

How contributions work

In 2026, a SEP-IRA lets a business put away up to $72,000 or 25% of a worker’s pay into a retirement account, whichever amount is smaller. Only the boss puts money into a SEP-IRA, so employees cannot add their own paycheck dollars. For regular workers, the math is simple: just multiply their yearly pay by the percentage the employer chooses to give.

For self-employed business owners, the math has a small twist because the owner acts as both the boss and the worker. Before figuring out the contribution, net business earnings must first be lowered by taking out half of the self-employment tax. Because of this extra tax adjustment, the maximum amount a self-employed person can actually contribute ends up being about 20% of their adjusted profits, rather than the full 25%.

The employee coverage obligation

The SEP-IRA’s simplicity comes with a requirement that applies to businesses with employees. The owner must contribute the same percentage of compensation to every eligible employee’s SEP-IRA as they contribute to their own. To be eligible, an employee must be at least 21 years old, have worked for the business in at least three of the past five years, and have earned at least $800 from that job in 2026. An owner who contributes 20 percent of their own compensation must also contribute 20 percent of each eligible employee’s compensation.

Setup deadline and flexibility

A SEP-IRA can be established and funded up to the tax filing deadline, including extensions, which means an owner who had a strong year can open one and fund it as late as October of the following year if they file for an extension. There are no annual filing requirements for the plan itself. There is also no requirement to contribute every year; the contribution can be reduced or skipped in lower-revenue years without violating the plan’s terms.

SIMPLE IRA

A SIMPLE IRA (Savings Incentive Match Plan for Employees) is a retirement plan designed for businesses with 100 or fewer employees that want a structure where both the employer and the employees contribute. It is less complex to administer than a 401(k) and requires a mandatory employer contribution.

Contribution limits for 2026

The 2026 SIMPLE IRA employee contribution limit is $17,000, with a $4,000 catch-up for those aged 50 to 59 and 64 and older, and a $5,250 super catch-up for those aged 60 to 63. Employers with 25 or fewer employees may offer an enhanced plan allowing contributions of up to $18,100. The employer contribution is mandatory and follows one of two formulas.

The employer contribution requirement

The $17,000 limit applies strictly to the employee’s salary deferrals (or $18,100 for businesses with 25 or fewer employees). For the employer’s contribution, there is no flat dollar cap; instead, employer contributions are calculated purely as a percentage of each employee’s salary.

Under a SIMPLE IRA, the employer must choose one of two funding options:

  • Matching Option: The employer matches employee contributions dollar-for-dollar up to 3% of compensation. Employers with 26 to 100 employees who allow higher employee limits must match up to 4% instead. The match percentage can drop to 1% for up to two out of every five years, but it cannot be eliminated completely.
  • Non-Elective Option: The employer contributes 2% of compensation for every eligible worker, regardless of whether the worker contributes. This calculation applies to compensation capped at $360,000 per employee.

The two-year rule

SIMPLE IRAs carry an important restriction that does not apply to other plans. Funds contributed to a SIMPLE IRA in the first two years of participation cannot be rolled over to a non-SIMPLE retirement account. Early withdrawals during that two-year window are subject to a 25 percent penalty rather than the standard 10 percent that applies to other IRA types.

Congress designed these strict rules to discourage employees from treating small-business retirement accounts like short-term savings funds. Because employers are legally required to make mandatory matching or non-elective contributions, lawmakers imposed the initial rollover restriction and the steep 25% penalty to ensure that employer-funded dollars stay in the plan and give the newly established account time to accumulate long-term savings stability.

Setup deadline

A SIMPLE IRA must be established by October 1 of the year it is intended to be effective. Unlike a SEP-IRA, it cannot be set up retroactively after the year ends.

Solo 401(k)

A Solo 401(k), also called a one-participant 401(k), is a 401(k) plan designed for self-employed individuals and business owners who have no full-time employees other than a spouse. It offers the highest contribution potential of any plan available to the self-employed and includes features not available in other plans, such as a Roth option and loan provisions.

Why the contribution structure is different

The Solo 401(k) allows contributions in two separate capacities. As an employee, the owner can defer up to $24,500 in salary in 2026, plus $8,000 in catch-up contributions if aged 50 to 59 or 64 and older, or $11,250 for the enhanced super catch-up if aged 60 to 63. As the employer, the owner can make additional profit-sharing contributions of up to 25 percent of compensation. The combined total from both sources cannot exceed $72,000 in 2026, or $83,250 for those using the enhanced super catch-up.

Why the Solo 401(k) outperforms the SEP-IRA at moderate incomes

At higher income levels, the SEP-IRA and Solo 401(k) produce similar contribution totals. At lower income levels, the Solo 401(k) produces a higher contribution because the employee deferral is a flat dollar amount rather than a percentage of income. For an owner with $120,000 in net self-employment income, the SEP-IRA would allow approximately $22,000 in contributions. The Solo 401(k) would allow the full $24,500 employee deferral plus a profit-sharing contribution of approximately $22,000, bringing the total to around $46,500.

Setup deadline and filing requirements

A Solo 401(k) must be established by December 31 of the tax year for which contributions are intended, even though the contribution itself can be made up to the tax filing deadline. Plans with assets exceeding $250,000 at year-end must file Form 5500-EZ with the IRS annually.

Traditional and Roth IRAs

A traditional IRA or Roth IRA is an individual retirement account that anyone with earned income can contribute to, regardless of business structure or whether they have a business retirement plan. For 2026, the contribution limit is $7,500 for those under 50 and $8,600 for those 50 and older, combining the base and the $1,100 catch-up. The limit applies across all IRAs combined, not separately.

How it interacts with a business plan

Having a SEP-IRA or Solo 401(k) affects whether a traditional IRA contribution is tax-deductible. Since a SEP-IRA or Solo 401(k) counts as a workplace retirement plan for IRS purposes, the deductibility of a traditional IRA contribution phases out at adjusted gross income between $81,000 and $91,000 for single filers and between $129,000 and $149,000 for married couples filing jointly in 2026. A Roth IRA contribution has its own income phase-out,running from $153,000 to $168,000 for single filers and $242,000 to $252,000 for married couples filing jointly.

When it makes sense alongside a business plan

For a small business owner who has already maximized a SEP-IRA or Solo 401(k), a Roth IRA provides tax-free growth and tax-free distributions in retirement, with no required minimum distributions during the owner’s lifetime. At higher income levels, contributing directly to a Roth IRA may not be possible due to income limits, but a Roth conversion from a traditional IRA can achieve a similar result.

Go Further: When should you hire a financial advisor? covers the specific situations where coordinating retirement plan selection with tax strategy benefits most from professional guidance, particularly in high-revenue years.

Comparing SEP-IRAs, Solo 401(k)s, and SIMPLE IRAs

Graphic by Kate Farley

When a SEP-IRA is best

The SEP-IRA wins on simplicity. There is no setup deadline pressure, no annual filing in most cases, no mandatory contribution, and no employee deferral to administer. For a solo operator or a small firm with employees who want flexibility and minimal overhead, the SEP-IRA is the most straightforward option.

When a Solo 401(k) is best

The Solo 401(k) wins at moderate incomes, for anyone who wants a Roth option, for anyone who wants the ability to take a plan loan, and for anyone aged 50 or older who wants the catch-up contribution that the SEP-IRA does not offer. For a solo business owner with no employees and a priority on maximizing tax-deferred savings, the Solo 401(k) is typically the more flexible and powerful structure.

When a SIMPLE IRA is best

The SIMPLE IRA is most practical for a business with employees that wants a straightforward plan without the complexity of a 401(k). The mandatory employer contribution is a real cost, but it also functions as an employee benefit that supports retention. For a business with a stable team and relatively predictable revenue, the SIMPLE IRA offers a workable structure that requires minimal administration once in place.

How to choose a retirement plan for your business

The most important filter is whether the business has full-time employees. A Solo 401(k) is only available to businesses with no full-time employees other than a spouse. If that condition is met, it is typically the first plan to consider for a self-employed individual, given its contribution flexibility and feature set.

For solo operators with high income

A self-employed individual with net earnings above $200,000 will generally be able to reach the $72,000 ceiling with either a SEP-IRA or a Solo 401(k). At that income level, the SEP-IRA’s simplicity may outweigh the additional features of the Solo 401(k). The ability to fund it up to the extended tax deadline makes it particularly useful when income varies significantly from year to year.

For solo operators with moderate income

At net earnings around $120,000, the Solo 401(k) will typically allow a higher total contribution than the SEP-IRA. The flat $24,500 employee deferral in the Solo 401(k) is not subject to the percentage-of-income formula that limits the SEP-IRA at lower earnings levels. For someone earning $120,000 in net self-employment income, the Solo 401(k) can produce contributions roughly $24,000 higher than the SEP-IRA in the same year.

For businesses with employees

When the business has a team, the Solo 401(k) is no longer available. The choice narrows to a SEP-IRA, a SIMPLE IRA, or a traditional group 401(k). The SEP-IRA’s proportional coverage requirement, which mandates the same percentage be contributed to every eligible employee, makes it expensive relative to the owner’s contribution when the team is large. The SIMPLE IRA caps the employer cost at 3 percent of each employee’s compensation, which makes it more predictable for budget planning.

For businesses that need contribution flexibility

Revenue variability is a real factor for small business owners. The SEP-IRA allows the contribution to be reduced to zero in a low-revenue year without penalty or plan termination. The SIMPLE IRA’s employer contribution is mandatory every year the plan is active, which creates an obligation even in years when the business would prefer to conserve cash. For businesses with seasonal or lumpy revenue, the SEP-IRA’s flexibility is a structural advantage.

Go Further: 9 states with no state income tax for retirees covers how state of residence interacts with retirement income, which becomes relevant when a small business owner is deciding where to operate and where to retire.

Tax benefits and contribution limits

Contributions to a SEP-IRA, Solo 401(k), or SIMPLE IRA are deductible in the year they are made. For a sole proprietor, those contributions reduce Schedule C income and the taxable income that flows through to Form 1040, lowering the federal income tax bill. For an S-Corp owner, contributions made through the business reduce W-2 wages and pass-through income accordingly.

How contributions can reduce federal income taxes

For a business owner whose taxable income falls in the 32 percent federal bracket, a $72,000 SEP-IRA or Solo 401(k) contribution reduces the federal tax bill by $23,040. For someone in the 37 percent bracket, the same contribution saves $26,640. The deduction does not reduce self-employment taxes for sole proprietors, but it does reduce the income included in the federal income tax calculation, generating real savings at every bracket level.

Roth contributions in a Solo 401(k)

Solo 401(k) plans that include a Roth feature allow the employee deferral portion to be designated as Roth. Those contributions receive no current-year deduction, grow tax-free, and are distributed tax-free in retirement. For a business owner who expects to be in a higher tax bracket in retirement than today, or who has significant pre-tax IRA balances that will generate required minimum distributions later, the Roth designation can be the more efficient long-term choice.

The Roth catch-up requirement for high earners

Starting in 2026, workers age 50 and older who earned more than $150,000 in prior-year FICA (Social Security/Medicare) wages from an employer must make any catch-up contributions to that employer’s plan on an after-tax Roth basis. This threshold is evaluated strictly on an employer-by-employer basis. Prior-year wages from an unrelated job or separate employer do not trigger the Roth requirement for a Solo 401(k).

For a Solo 401(k), the Roth catch-up rule applies only if the business owner was paid over $150,000 in W-2 wages directly from their own business in the previous tax year. If this threshold is met, any catch-up contributions made to the Solo 401(k) must be designated as Roth. If the Solo 401(k) plan does not currently support a Roth feature, the business owner cannot make catch-up contributions at all until the plan is updated.

Contribution deadlines by plan type

The contribution deadline matters for tax planning. SEP-IRA contributions can be made up to the tax filing deadline, including extensions, giving a sole proprietor or S-Corp owner until October 15 of the following year to fund the account. Solo 401(k) employee deferrals must typically be made by December 31 of the tax year, though the employer profit-sharing portion can be made up to the filing deadline. SIMPLE IRA contributions are funded through payroll throughout the year and cannot be made retroactively.

Go Further: Understanding the “tax torpedo” in Social Security covers how large required minimum distributions from pre-tax retirement accounts interact with Social Security taxation in retirement, which is directly relevant to the pre-tax versus Roth choice for business owners building large balances.

How a financial advisor can help

The plan selection decision has a built-in deadline. A Solo 401(k) must be established by December 31, a SIMPLE IRA by October 1, and the SEP-IRA, while flexible on funding, still requires the right structure to be in place for the contributions to be eligible. A fee-only fiduciary can model the contribution and tax impact of each option across the current year and several projected years before any setup paperwork is filed.

Coordinating the plan with the broader tax picture

For business owners with both a business retirement plan and a spouse’s workplace plan, or with W-2 income alongside self-employment income, the interaction among multiple plans adds complexity, making the decision more consequential. The Roth catch-up rule, the SIMPLE IRA two-year restriction, and the IRA deductibility phase-outs all create variables that interact differently depending on the specific income mix.

Planning for employees from day one

A Solo 401(k) owner who hires a full-time employee must generally terminate the Solo 401(k) and transition to a plan that covers the new team member. That transition has timing requirements and rollover mechanics that are easier to navigate with advance planning than after the hire has already happened. A financial advisor can help structure the plan choice with an eye toward the business’s anticipated growth rather than only the current year’s income.

Modeling the long-run outcome

The plan-type decision affects not just this year’s tax bill but the trajectory of the retirement account over the next 10 to 20 years. For a 52-year-old business owner with $400,000 in existing retirement assets, the question of whether to contribute $72,000 pre-tax to a SEP-IRA or to use the Solo 401(k)’s flexibility to designate the $24,500 employee deferral as Roth while taking the $47,500 employer profit-sharing contribution as a pre-tax deduction has different projected after-tax outcomes at age 72, 75, and 80. Those differences depend on the assumed tax rate, the RMD trajectory, and the Social Security timing, and running those projections before choosing the plan structure is the most direct way to make the decision based on actual expected outcomes.

FAQs

Can a small business owner have both a Solo 401(k) and a SEP-IRA?

Generally, no. A business cannot maintain both a Solo 401(k) and a SEP-IRA in the same tax year for the same business. However, a self-employed person who also has W-2 income from an unrelated employer and participates in that employer’s 401(k) can still establish a Solo 401(k) or SEP-IRA for their self-employment income, subject to the combined limits.

Can a self-employed person contribute to a SIMPLE IRA?

Yes. A self-employed individual with no other employees can establish and contribute to a SIMPLE IRA, serving as both the employer and the employee. However, the contribution limits are lower than a SEP-IRA or Solo 401(k) at most income levels, and the mandatory employer contribution requirement applies even when the owner is the only participant.

What happens to a Solo 401(k) if the business hires employees?

When a business operating a Solo 401(k) hires a full-time employee who meets the plan’s eligibility requirements, the Solo 401(k) can no longer operate as a one-participant plan. The owner must either expand the plan to cover the new hire, converting it into a traditional 401(k) with associated compliance requirements, or terminate the Solo 401(k) and transition to a different plan type. A plan administrator or financial advisor should be involved in the timing of that transition.

Is a SEP-IRA better than a Solo 401(k)?

Neither is categorically better. The SEP-IRA is simpler to set up and administer, offers flexibility in contribution amounts, and is usable by businesses of any size. The Solo 401(k) allows higher contributions at moderate income levels, includes an optional Roth feature, and offers catch-up contributions for those 50 and older that the SEP-IRA does not. The better choice depends on income level, whether employees are involved, and whether the Roth option matters for the owner’s long-term tax strategy.

What is the easiest retirement plan for a small business to set up?

The SEP-IRA is generally considered the easiest to establish and maintain. It requires a simple IRS form, has no annual filing requirement for most plans, and can be opened and funded up to the extended tax deadline. For a solo operator looking to reduce taxable income with minimal administrative overhead, it is typically the most accessible starting point.

Glossary

SEP-IRA (Simplified Employee Pension IRA): An employer-funded retirement account available to businesses of any size and to self-employed individuals. Contributions are made solely by the employer, up to 25 percent of eligible compensation or $72,000 in 2026, whichever is lower. The same contribution percentage must be applied to all eligible employees. No catch-up contributions are available, and the account can be established up to the tax filing deadline.

SIMPLE IRA (Savings Incentive Match Plan for Employees IRA): A retirement plan for businesses with 100 or fewer employees where both the employer and employees contribute. The 2026 employee limit is $17,000, with catch-up provisions for older participants. The employer is required to either match employee contributions up to 3 percent of compensation or make a 2 percent non-elective contribution for all eligible employees. Must be established by October 1 of the plan year.

Solo 401(k): A 401(k) plan for self-employed individuals and business owners with no full-time employees other than a spouse. Allows contributions in both the employee deferral and employer profit-sharing roles. The 2026 employee deferral limit is $24,500, with catch-up provisions for those 50 and older. The overall annual limit from both sources is $72,000. Must be established by December 31 of the tax year.

Elective deferral: The portion of a 401(k) or SIMPLE IRA contribution made from the participant’s own pay through a salary reduction agreement. The employee deferral limit for a Solo 401(k) is $24,500 in 2026. Distinct from employer profit-sharing contributions, which are calculated as a percentage of compensation.

Non-elective contribution: An employer contribution to a retirement plan that is made regardless of whether the employee contributes anything. In a SIMPLE IRA, the non-elective option is a flat 2 percent of each eligible employee’s compensation. Distinct from a matching contribution, which is conditional on the employee contributing.

Super catch-up: The enhanced catch-up contribution tier available under SECURE 2.0 for retirement plan participants who turn 60, 61, 62, or 63 during the calendar year. In 2026, the super catch-up for Solo 401(k) participants is $11,250, compared to the standard $8,000 for other age groups. For SIMPLE IRA participants, the super catch-up is $5,250.

Required minimum distribution (RMD): The annual withdrawal the IRS requires from tax-deferred retirement accounts, including traditional IRAs, SEP-IRAs, SIMPLE IRAs, and 401(k)s, beginning at age 73. Calculated from the prior year-end account balance and the IRS Uniform Lifetime Table. Roth IRAs are not subject to RMDs during the owner’s lifetime.

Two-year rule: The SIMPLE IRA-specific restriction preventing funds contributed in the first two years of participation from being rolled over to a non-SIMPLE retirement plan. Early withdrawals during this window carry a 25 percent penalty rather than the standard 10 percent that applies to other IRA types.

Form 5500-EZ: The annual IRS filing required for Solo 401(k) plans with assets exceeding $250,000 at the end of the plan year. Solo 401(k) plans below that threshold are generally exempt from annual filing requirements.

Profit-sharing contribution: The employer portion of a Solo 401(k) contribution, calculated as up to 25 percent of the owner’s W-2 compensation for an S-Corp, or approximately 20 percent of net self-employment earnings for a sole proprietor. Added to the employee deferral to produce the total annual contribution, subject to the $72,000 overall limit.

Sources