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Sometimes SIMPLE Isn't

DWC Knowledge Center Article: What is the Difference Between a SIMPLE, SEP, and 401(k) Plan?

One of the most frequent phone calls we receive — whether from a small business owner or an advisor working with one — starts something like this: "I [or my client] want to set up a retirement plan, but it has to be simple and the lowest cost possible."

What could be a better fit than a plan that has the word “simple” in its name? Sometimes, that is a great place to start. Other times, however, “simple” really isn’t.


In addition to the 401(k) plan, Congress created several other types of retirement plans that are intended to be easy for small businesses to setup and maintain. They are the Simplified Employee Pension (“SEP”) and the Savings Incentive Match Plan for Employees or “SIMPLE” (how many hours did Congressional staffers sit around trying to come up with that name). The SIMPLE comes in two flavors: the SIMPLE IRA and the SIMPLE 401(k).

Although all three of these options require minimal documentation, no annual testing and limited (if any) ongoing government filings, each imposes limitations that often lead to a regular 401(k) plan being an equally cost-effective option.

What's the Difference and Does It Matter?

There are some significant differences that set these plans apart from one another. Even if one of the “simple” variety is a good fit now, it is a good idea to keep the differences in mind as needs change.

Size Is Important

Employers of any size can implement SEPs and 401(k) plans; however, SIMPLE plans are only available for companies with 100 or fewer employees with at least $5,000 in compensation during the immediately preceding calendar year. 

Exclusive Plan

A SIMPLE plan must be the only plan an employer maintains in a given calendar year. This most often comes into play when a company decides to transition from a SIMPLE to a regular 401(k) plan. Such a transition can only occur at the beginning of a subsequent year, and employers must generally provide the employees with advance notification of the discontinuance of the SIMPLE. So if you or your client are considering a transition, you will generally want to get started no later than October 1 to prepare for the upcoming year.

There is no similar requirement that applies to SEPs and 401(k) plans, so employers can maintain multiple plans or transition from one type to another without concern for the “exclusive plan” requirement.


401(k) plans and SIMPLE 401(k) plans are allowed to have eligibility requirements as strict as attainment of age 21 and completion of one year of service. For this purpose, a year of service is a 12-consecutive-month period in which an employee works at least 1,000 hours.

By contrast, neither SEPs nor SIMPLE IRAs can limit eligibility the same way. In a SIMPLE IRA, the maximum is to limit eligibility to those employees who have earned at least $5,000 in compensation in the two prior years and are expected to again in the current year. SEPs can limit plan coverage to those employees who have earned at least $550 in compensation in at least three of the last five years. There is no ability to exclude short service employees – interns, etc. — if they meet these requirements.

Employee Deferrals

Unless adopted prior to 1997, salary deferrals are not allowed in SEPs. Both SIMPLEs and 401(k) plans allow deferrals, but there are some critical differences.

First, a 401(k) plan allows deferrals up to $23,000 per year ($17,500 plus an additional $5,500 for those age 50 or older). A SIMPLE, on the other hand, caps deferrals at $14,500 ($12,000 plus $2,500) — a whopping $8,500 less. For a business owner who wishes to maximize his or her deferrals, the tax savings alone can more than offset any additional cost of having a regular 401(k) plan.

Another important difference is that SIMPLE plans do not allow Roth deferrals, which could limit the plan’s utility as an estate planning tool.

Employer Matching Contributions

SIMPLE plans carry a mandatory company contribution, which can be either a match or profit sharing contribution. If the match is chosen, the mandatory formula is 100% of the first 3% deferred. No additional matching contributions are permitted.

A 401(k) plan can include a discretionary matching feature, meaning the company can decide from year to year whether to make a match and, if so, how much. Companies that prefer to “buy their way” out of certain 401(k) compliance tests can agree to a fixed safe harbor matching formula of 100% of the first 3% deferred plus 50% of the next 2% deferred.

SEPs do not allow matching contributions.

Employer Profit Sharing Contributions

Employers that elect the profit sharing option for their SIMPLE plans must contribute 2% of compensation for each eligible employee. No additional profit sharing contributions are permitted.

SEPs and 401(k) plans allow discretionary profit sharing contributions of up to 25% of pay in total and no more than $51,000 per employee. Again, that discretion provides business owners with flexibility as to if/how much they wish to contribute. As an alternative to the two-tiered match safe harbor (previously described), a 401(k) plan can make a safe harbor profit sharing contribution equal to 3% of pay.

With a SEP, each employee must receive a uniform contribution (as a percentage of pay). So, if the owner contributes 10% of pay for him or herself, each employee must also receive 10% of pay. In a 401(k) plan, there is much greater flexibility to provide larger contributions to those who earn more than the taxable wage base (referred to Social Security Integration) or target contributions based on job classification, e.g. owners and non-owners.


A 401(k) plan can impose a vesting schedule of up to six years on employer contributions (other than safe harbor contributions); however, both SIMPLEs and SEPs require employees to be immediately vested in all company contributions.

Loans and In-Service Withdrawals

Neither SEPs nor SIMPLEs allow participant loans like 401(k) plans do. If a participant takes an in-service withdrawal from a 401(k) plan prior to age 59 ½, it is subject to regular income tax as well as a 10% early withdrawal penalty. SEP distributions are taxed similar to distributions from a regular IRA, and those rules generally resemble the 401(k) rules. For a SIMPLE, however, if withdrawals are made within the first two years of participation, the 10% penalty is increased to 25%!

Plan Documents

All of these plan types require some form of documentation of the plan and its provisions. For SEPs and SIMPLEs that truly keep it simple — little (if any) creativity in plan design, no related companies or complex ownership structures, etc. — the IRS has forms (allegedly DIY) that can be used.

  • Form 5305-SEP
  • Form 5304-SIMPLE: allows each eligible employee to select his or her own financial institution. The obvious downside is in a 10 employee company, the plan sponsor could effectively have to send contributions to 10 different custodians each pay period.
  • Form 5305-SIMPLE: the employer selects a single financial institution for all plan accounts.

A 401(k) plan or a SEP/SIMPLE that cannot use the IRS form must use a more traditional plan document, which can follow an IRS pre-approved format such as a prototype or be individually customized. Many mutual fund families and other financial institutions offer DIY prototypes which may look straight-forward on the surface; however, given the importance of the plan document, we recommend working with someone with expertise in that area.

Annual Compliance Testing

SEPs and SIMPLE IRAs are not required to go through the battery of annual compliance tests. However, as we have described in this article, there are plenty of rules that must be monitored to ensure ongoing compliance. SIMPLE 401(k) plans are required to satisfy the minimum coverage test but are exempt from most of the other tests normally associated with retirement plans. A traditional 401(k) plan must comply with a series of tests to ensure enough of the rank and file employees are receiving adequate benefits, but given the added flexibility of plan design, the testing can be a trade-off that is well worth it.

Government Reporting

Similar to annual testing, neither the SEP nor the SIMPLE IRA is required to file a Form 5500 each year; whereas, both the SIMPLE 401(k) and the “regular” 401(k) must do so. In addition, they must file Form 8955-SSA to report former employees with remaining balances in the plan.


SEPs and SIMPLEs can be extremely effective tools for meeting the retirement plan needs of small businesses, but they can be far from simple. Given the flexibility in plan design – from initial eligibility to targeting company contributions to key individuals – a full-blown 401(k) plan can often provide benefits to the business owner and employee alike that far surpass the additional cost that may come with it.

The bottom line is that since “simple” sometimes isn’t, it is of critical importance to work with experts who understand the ins and outs, can help you articulate your plan-related objectives and analyze the options to ensure you have the best plan to meet your needs. Where do you find such an expert? Simple! Just give us a call.

Download the Plan Design Comparison Quick Reference Chart here