If you run a small business, choosing a retirement plan can feel like picking a software platform. Everything sounds similar until you realize one option locks you into ongoing costs, while another gives you flexibility but comes with fine print.
Two of the most common “starter” retirement plans for small employers are the SEP IRA and the SIMPLE IRA. Both can be great. They just solve different problems.
Below, I will walk you through the differences that actually matter in real life: who can use each plan, how much you can contribute, what you must contribute for employees, what it costs to run, what’s changed recently, and how to decide based on your team and payroll budget.
Quick take: best use cases
- SEP IRA: Best when you want high contribution potential and maximum flexibility year to year, especially if you are self-employed or have a small team. Employer contributions only, no employee salary deferrals.
- SIMPLE IRA: Best when you want employees to contribute from their paycheck and you are comfortable with mandatory employer contributions (match or nonelective) each year.
Keep that framing in mind as we go, because the “best” plan is usually the one that matches how predictable your payroll and cash flow are.
SECURE 2.0 updates to know
Two changes from the SECURE 2.0 Act are worth calling out because they affect how these plans feel in day-to-day use:
- Roth is now permitted in new ways (if your provider supports it and the IRS guidance is implemented). In a SIMPLE IRA, employee salary deferrals may be made as Roth. Separately, SECURE 2.0 also allows certain employer contributions in SEP and SIMPLE arrangements to be treated as Roth, if the plan and custodian support the required reporting and mechanics. The takeaway: Roth may be available, but it does not work the same way in every plan and not every provider has rolled it out.
- SIMPLE IRAs can allow an additional employer nonelective contribution. Beyond the required 2% nonelective contribution or the match, SECURE 2.0 permits employers to make an optional additional nonelective contribution, subject to conditions and caps (commonly described as up to 10% of compensation or a statutory dollar cap). Because the dollar cap can be updated or clarified by guidance, verify the current-year limit and eligibility conditions with your provider or advisor.
Not every custodian has rolled out every feature the same way, so treat this as “now permitted” and confirm availability with your provider.
SEP IRA vs SIMPLE IRA at a glance
| Feature | SEP IRA | SIMPLE IRA |
|---|---|---|
| Who contributes | Employer only | Employees and employer |
| Best for | Owners who want high, flexible contributions | Small teams who want paycheck contributions |
| Employee limit to use | No specific employee cap, but must cover eligible employees | Generally for employers with 100 or fewer eligible employees under IRS counting rules |
| Employer contribution requirement | Optional each year (if you contribute, it must be equal % for eligible employees) | Required each year: match or 2% nonelective |
| Contribution ceiling | Higher potential; employer contribution can be large | Lower overall; employee deferral plus employer contribution |
| Setup complexity | Very simple | Still simple, slightly more admin due to payroll deferrals |
| Common gotcha | If you contribute for yourself, you may have to contribute for employees at the same rate | Employer contribution is not optional, and early withdrawals can be hit harder |
Note: Contribution limits and thresholds change over time. The examples below use 2024 figures for clarity, but always confirm current-year numbers with the IRS or your plan provider.
Eligibility: who can set up each plan
SEP IRA eligibility
A SEP IRA can be adopted by most small businesses: sole proprietors, partnerships, corporations, and LLCs. It is popular for self-employed owners because it is straightforward and contributions can be decided later in the year.
For employees, SEP rules require you to cover workers who meet certain criteria (often: age 21+, worked for you in at least 3 of the last 5 years, and earned at least a minimum compensation threshold set by the IRS). That compensation threshold is indexed annually, so check the current-year amount. Your plan document can be more generous, but not more restrictive than allowed.
SIMPLE IRA eligibility
A SIMPLE IRA is intended for smaller employers and is typically available if you have 100 or fewer employees under a specific lookback test (based on employees who received at least a minimum amount of compensation in prior years). Most summaries describe it as “100 or fewer employees who earned $5,000+,” but the counting rules have details, so confirm if you are near the limit.
Employees usually become eligible if they earned at least $5,000 in any two prior years and are expected to earn at least $5,000 in the current year. The practical difference is that SIMPLE IRAs are built around payroll deferrals, so you need payroll processes that can handle recurring contributions.
Contribution limits: how much you can put away
SEP IRA contributions
With a SEP IRA, only the employer contributes. Contributions are based on a percentage of compensation, up to IRS limits. As a rule of thumb, the SEP contribution is up to 25% of eligible compensation, subject to an annual dollar cap and compensation limits.
One nuance that surprises founders: if you have eligible employees and you decide to contribute for yourself, you must contribute the same percentage of pay for eligible employees. So a 20% contribution for you can mean a 20% contribution for them, too.
Concrete number (2024 example): In 2024, the SEP contribution cap is up to $69,000 (subject to compensation limits and the percentage-of-pay formula). That is why SEPs are often described as having “high contribution potential.”
Self-employed owners note: If you are a sole proprietor or partner, the SEP math uses your net earnings from self-employment and includes an adjustment related to self-employment tax. Practically, that means the effective “percentage” can land lower than you expect. Your tax pro or provider worksheet can help you calculate it correctly.
SIMPLE IRA contributions
SIMPLE IRAs allow employees to contribute via salary deferral, up to an annual limit set by the IRS (with an additional catch-up amount allowed for older participants). On top of that, the employer must contribute each year using one of the required methods described below.
Concrete number (2024 example): In 2024, the employee salary deferral limit is $16,000 (plus catch-up if eligible). Employer contributions are on top of that, but SIMPLE totals still tend to come in lower than a maxed SEP for high earners.
Quick reality check: SEP “higher” is not automatically “better.” If you have employees, the SEP equal-percentage rule can make a high owner contribution expensive fast. SIMPLE contributions are often easier to budget because the employer formula is known up front.
Employer contributions: optional vs required
SEP IRA: flexible, but equal treatment
The SEP IRA is flexible because you can decide whether to contribute each year. That is helpful if your business cash flow swings. If you have a lean year, you can contribute less or even zero.
The tradeoff is equal treatment: when you do contribute, you must contribute the same percentage of compensation for each eligible employee as you contribute for yourself.
SIMPLE IRA: required every year
With a SIMPLE IRA, the employer contribution is not optional. You choose one of these approaches:
- Match contributions: A match up to 3% of an employee’s compensation. The rules also allow a reduced match as low as 1% in no more than 2 out of 5 years.
- Nonelective contributions: A 2% contribution for each eligible employee, whether they defer or not (based on compensation up to an IRS cap).
If you like predictable budgeting, a SIMPLE IRA can be easier to forecast. If you want the ability to hit pause during a tough year, the SEP IRA usually wins.
Setup and admin
SEP IRA costs
SEP IRAs are often inexpensive to establish and run, especially compared with a 401(k). Many brokerages and custodians offer SEP accounts with no setup fee. Administration is light because there are no employee deferrals running through payroll.
Funding timing: A big practical advantage of a SEP is that employer contributions can usually be made up to your business tax-filing deadline, including extensions, as long as the plan is set up by the applicable deadline. That can make year-end planning much easier.
SIMPLE IRA costs
SIMPLE IRAs are still relatively easy (and typically lower-cost than a 401(k)), but there is more coordination: employee elections, payroll deductions, and regular deposits. Many providers make this painless, especially if you use integrated payroll software, but it is still another moving piece.
Also, providers vary. Some charge per participant, some charge for payroll integration, and some bundle everything. It is worth asking about the fee schedule up front so your “simple plan” stays simple.
Timing: A SIMPLE IRA generally must be established by October 1 to be effective for that year (with special rules for new businesses).
Deposit mechanics: SIMPLE employee deferrals must be deposited promptly after each payroll. The exact deadline can depend on employer size and facts, so coordinate with your payroll provider to avoid late deposits.
Tax benefits
Both SEP and SIMPLE IRAs are designed to give you tax advantages:
- Employer contributions are typically tax deductible to the business (subject to IRS rules).
- Employee salary deferrals in a SIMPLE IRA are typically pre-tax (reducing taxable income for the employee), and Roth treatment may be available if supported.
- Investments grow tax-deferred until distributions begin (Roth accounts follow Roth distribution rules).
Both plans also support a powerful behavioral benefit: they automate long-term saving. In my experience, automation is the real “secret sauce” behind retirement success, especially for busy owners.
How to choose
If you are solo (no employees)
Either can work, but the decision usually comes down to contribution goals and simplicity:
- Choose a SEP IRA if you want the potential for higher contributions and you like the idea of deciding the amount later.
- Choose a SIMPLE IRA if you want to contribute steadily from each paycheck and prefer a set-it-and-forget-it rhythm.
If you have a few employees
This is where the differences matter most.
- Choose a SIMPLE IRA if you want employees to contribute from their pay and you are comfortable committing to a match or 2% contribution each year.
- Choose a SEP IRA if you may not want to commit every year and you are okay with the fairness rule of contributing the same percentage for eligible employees when you do contribute.
If your payroll budget is tight or unpredictable
A SEP IRA often fits better because contributions can be reduced or skipped in a down year. A SIMPLE IRA can still be manageable, but remember the employer contribution is required, so you should be confident you can fund it even in a rough quarter.
If your employees want a 401(k)-like experience
A SIMPLE IRA usually feels closer to what employees expect because they can elect a deferral percentage and see it come out of payroll. A SEP IRA, while valuable, can feel more like a bonus because employees cannot defer their own pay into it.
Simple math examples
Example 1: Solo owner
You are a solo owner with $150,000 of compensation and want to save aggressively.
- SEP IRA: If you target a 20% employer contribution, that is roughly $30,000 (subject to the SEP formula and IRS limits, and the self-employed calculation rules if applicable).
- SIMPLE IRA: You might defer up to the annual employee limit (2024 example: $16,000), plus an employer match or 2% nonelective contribution.
This is why SEPs often win for higher-income solo owners who want to push contributions up.
Example 2: Owner plus three employees
You pay yourself $120,000 and you have three employees making $60,000 each.
- SEP IRA at 15%: You contribute $18,000 for yourself. You also contribute 15% for each eligible employee, which is $9,000 each, or $27,000 total. Your total employer cost is $45,000.
- SIMPLE IRA with a 3% match: If each employee defers enough to get the full match, you pay 3% of payroll. On $180,000 of employee payroll, that is $5,400, plus the match on your own deferrals if you participate.
These are simplified illustrations, but they capture the core tradeoff: SEP costs can jump when you raise your own percentage, while SIMPLE costs are tied to a known formula.
Real-world scenarios
Scenario 1: Freelance consultant with volatile income
You net $80,000 one year, $140,000 the next, and you want the option to contribute big when business is strong. A SEP IRA is often a better fit because you can adjust contributions annually without committing to a formula tied to employee deferrals.
Scenario 2: Small agency with three full-time employees
You want to offer a clear benefit and help your team save. Your payroll is stable. A SIMPLE IRA is often a great match because employees can contribute each pay period and you can budget the employer match.
Scenario 3: Family business payroll
Be careful with a SEP IRA here. If your spouse or sibling is an eligible employee, and you contribute for yourself, you need to contribute the same percentage for them. Sometimes that is fine. Sometimes it becomes more expensive than expected.
Common pitfalls
- Assuming SEP contributions are “just for me.” If you have eligible employees, SEP rules require proportional contributions.
- Forgetting the SIMPLE IRA employer requirement. The match or nonelective contribution is required each year.
- Missing the SIMPLE IRA deadline. A SIMPLE IRA is typically adopted by October 1 to be effective that year (special rules may apply for new businesses).
- Not coordinating with payroll. SIMPLE IRA deferrals need clean payroll processes and timely deposits.
- Ignoring early withdrawal rules. Early distributions are typically subject to a 10% penalty, but SIMPLE IRAs can be hit with a 25% penalty if taken within the first two years of participation (in addition to income taxes).
When neither is ideal
Sometimes SEP and SIMPLE are both the wrong tool, even if they are the easiest to start.
You may want to look at a (Solo) 401(k) instead if you want features like higher employee deferral limits, plan loans, or specific safe harbor designs. If Roth flexibility is your main goal, note that Roth features for SEP and SIMPLE are now permitted under SECURE 2.0, but availability and mechanics depend on the provider.
Also important: a SIMPLE IRA generally requires that you do not maintain another qualified plan for the same employees in the same year. If you are considering adding a 401(k) soon, keep that in mind before you commit.
FAQ
Can I have both a SEP IRA and a SIMPLE IRA?
Typically, an employer cannot maintain both plans covering the same employees in the same year. If you are considering switching, talk with a tax professional or plan provider about timing and coordination.
Which is better with no employees?
Many solo owners choose a SEP IRA for flexibility and contribution potential. A SIMPLE IRA can still be a good choice if you prefer steady paycheck deferrals and do not need the higher SEP-style contribution amounts.
Is a SIMPLE IRA the same as a SIMPLE 401(k)?
No. They are different plans with different rules and administration. A SIMPLE IRA is generally easier to run and is IRA-based, while a SIMPLE 401(k) is a 401(k) plan with its own requirements.
Do I need a CPA to set one up?
Not necessarily. Many custodians can help you open and administer the account. That said, it is smart to loop in a CPA or CFP professional when you are unsure about employee eligibility, contribution calculations (especially for self-employed income), Roth availability, or how the deduction flows through your business tax return.
My decision checklist
If you want a quick way to decide, start here:
- Do you want employees to contribute from payroll? Yes points to SIMPLE IRA.
- Do you need the option to skip employer contributions in a down year? Yes points to SEP IRA.
- Do you want the highest possible owner contribution and your income is strong? Often SEP IRA.
- Do you want a predictable benefit you can explain in one sentence to your team? Often SIMPLE IRA.
- Do you plan to add a 401(k) soon? Be careful with SIMPLE IRA timing, since you typically cannot run another qualified plan in the same year for the same employees.
When in doubt, run a quick cost estimate for each plan using your current payroll and a “what if revenues drop 20%” scenario. The plan that still feels comfortable in the down scenario is usually the one you will stick with long enough for it to matter.
