Case Study: How Plan Design Improved Participation Rates and Compliance

July 24, 2025

Many companies, especially in the professional services sector—law firms, staffing agencies, engineering and consulting companies, healthcare groups, etc.—are often made up of various employee tiers. For example, in a given company, you might find partners or executives in one segment, professional staff in another, and support staff or hourly workers in yet another. 


While this tiered structure works well operationally, it can pose challenges relating to retirement plan compliance. In one recent example, the Primark Benefits team helped a client with over 3,500 employees overcome a complicated compliance issue by strategically changing the plan design, first expanding eligibility and then implementing automatic enrollment. Let’s take a look. 

The Compliance Challenge 


In the pension industry, retirement plan testing rules exist primarily to ensure plans don’t disproportionately favor Highly Compensated Employees (HCEs) (which for 2025 is defined as most owners and anyone earning more than $160,000). These tests are crucial for maintaining the qualified status of a retirement plan, not to mention avoiding potential penalties or corrective actions. 


Two such tests are the coverage test and the Actual Deferral Percentage, or ADP, test. Briefly, the coverage test reviews which employee segment(s)  are covered by the plan, while the ADP test reviews employee deferral rates. When an employer includes only some employee segments in their retirement plan while excluding others, the plan has a higher chance of failing these tests, creating an administrative burden and budget headache for the employer. 


One of Primark Benefits’ clients is a staffing, or “temp”, agency. The company employs 3,500 people, divided into two distinct groups of workers: temps, who are placed on external client assignments, and internal back-office staff, who average a longer company tenure than the temp population. For years, only the office staff were eligible to participate in the 401(k) plan; temp workers were excluded. 


This tiered structure created a persistent plan compliance issue. Because the plan covered only a small portion of the total workforce, advanced analysis and additional testing were required each year to ensure the plan passed the coverage test. 


First Recommendation: Expanding Eligibility


To address this, we recommended expanding eligibility to include the temp workers, which the company elected to do two years ago. This was a big win from a coverage standpoint, as including everyone in the plan resolved many of the testing concerns tied to eligibility. 


However, it introduced a new issue: while all employees were now eligible to participate, many of the temp workers who are typically not Highly Compensated Employees) chose not to defer, lowering the overall rate of employee contributions among this group. We often see this occur  in employee segments that have relatively lower or more intermittent earnings. When it does, the plan is at risk of failing the ADP test. This in turn can result in corrective distributions (refunds) being required to some employees, potentially undermining their retirement savings goals. 


Second Recommendation: Add Auto Enrollment 


To get ahead of this, our team recommended implementing automatic enrollment, as opposed to requiring employees to actively select enrollment as an option. Nationally, auto-enrollment has increased participation in retirement plans, especially among employee groups that might not otherwise take action. It’s not just a compliance strategy: it’s a way to ensure more employees are saving for retirement, with minimal friction. 


Proactive adjustments like auto enrollment are especially valuable in dynamic workforces, such as staffing or seasonal industries, where high turnover and variable hours can otherwise make participation (and therefore maintaining compliance) a persistent challenge. 


Early Results and Next Steps 


Implementing our recommendations is already paying off. With a full year of auto-enrollment now under the client’s belt, the early data looks promising: Participation rates among newly eligible employees—especially those in traditionally lower-participating groups—have increased sharply, and next year’s ADP test result is projected to improve dramatically. Their actions not only boosted plan compliance; they also support broader retirement readiness across the workforce. That’s a clear success in our book. 


Exploring Additional Recommendations 


We're also working with the client on a few additional advanced strategies to further support compliance and flexibility: 


  • Potential plan restructuring: We’re exploring the possibility of carving out a subset of employees into a separate retirement plan. When appropriate, this approach can allow for more tailored plan features—such as different eligibility rules, contribution formulas, or vesting schedules—that better align with the needs of each employee group. It can also improve nondiscrimination test results by reducing demographic imbalances that commonly occur in mixed-employee populations. 
  • Non-Qualified Plan options: If HCE refunds remain an issue, a Non-Qualified Deferred Compensation (NQDC) plan could offer a way for those employees to continue deferring income, even if the 401(k) limits are reached. While NQDCs don’t offer the same tax benefits as qualified plans, they still provide value—especially for retaining and rewarding key employees. We’ll discuss this complex topic in a future blog article. 
     

Takeaways 



For employers navigating complex workforce structures, staying ahead of nondiscrimination testing isn’t just about passing IRS rules—it’s about delivering a functional, equitable retirement plan that meets business goals and employee needs alike. 


This case is a great example of how adjustments to plan design can have a big impact. When done thoughtfully, these changes can increase participation, improve compliance, and create a better retirement plan experience for everyone involved. 


The team at Primark Benefits has the track record of success and deep expertise in working with complex plans and delivering unique solutions. Contact us to learn more. 

September 15, 2026
The Challenge Sometimes the most expensive retirement plan mistakes aren't dramatic. They're quiet. A former client of ours changed retirement plan providers following an acquisition several years prior. On the surface, everything appeared to be operating normally after moving to the new provider: employees continued making contributions to the plan, the plan’s investments remained in place, and the business continued its normal operations. Then another merger opportunity came along. As part of their due diligence process, the buyers reviewed the retirement plan. What they found immediately raised concerns. The annual Form 5500 filings required by ERISA law had not been submitted for several years. That also meant that none of the required compliance testing had been completed, and routine administrative responsibilities had also gone undone. What had started as a routine review quickly became a significant obstacle to completing the business sale. The Hidden Risk Many employers assume that once a retirement plan provider is hired, responsibility for the plan’s ongoing administration has effectively been transferred to that provider. But a plan sponsor is never completely relieved of its responsibility to oversee the plan. Even when outside providers are hired to handle filings, testing, recordkeeping, or other administrative functions, the employer still needs to make sure those responsibilities are being fulfilled. At the same time, there is an important difference between a provider that simply waits for the employer to supply information and one that actively works with the employer to make sure the plan stays on track. In this case, some of the missing work may have resulted from information requested by the provider that was never supplied by the employer. Technically, the employer still had a responsibility to provide that information and ensure the work was completed. But years of required administration should not quietly disappear into a communication gap. A proactive administrator follows up. If the usual contact isn’t responding, they escalate the issue. They make sure the appropriate people understand what is outstanding, why it matters, and what could happen if it isn’t addressed. Retirement plans require ongoing attention every year, including government filings, compliance testing, participant administration, documentation, and, when necessary, operational corrections. When those responsibilities are neglected, the consequences may not become obvious immediately. Instead, problems can accumulate quietly in the background until an IRS inquiry, Department of Labor investigation, audit, or—as in this case—a business transaction suddenly exposes years of unresolved issues. The prospective buyer made it clear that the retirement plan issues needed to be addressed before the transaction could move forward. The Rescue Knowing we had previously administered their plan, the current company leadership contacted us. Our first step was to determine the full scope of the problem. The timing made the situation particularly challenging. This wasn’t simply a retirement plan cleanup project. A business transaction was underway, and the company needed answers quickly. We assembled a team to determine the full scope of the problem and begin developing a path forward. Because we have deep experience with taking over neglected plans, we were able to separate perceived problems from actual compliance issues and reconstruct the plan's history. In reviewing the prior documentation, we identified exactly which administrative functions had been completed and which had been missed. We gathered historical payroll and participant data and developed a comprehensive correction strategy. Having access to historical plan records was especially important. Retirement plan problems may not surface until years after the underlying event, making good record retention critical. If you’re curious about how long to hold onto plan documentation, please see our blog post here . The final correction effort proved to be far more manageable than originally feared. Instead of allowing uncertainty around the retirement plan to continue hanging over the transaction, the employer now understood what had actually gone wrong, what needed to be corrected, and what steps were required to move forward. The Outcome With the correction efforts clarified and a clear roadmap in place, the employer was able to begin correcting the plan and continue moving toward its business transaction. More importantly, the company avoided entering the acquisition process with unresolved retirement plan liabilities hanging over or ruining the deal. The experience also reinforced an important lesson: Changing retirement plan providers doesn't eliminate administrative responsibilities. But it also demonstrated why the quality of the administrator matters. A good retirement plan administrator doesn’t simply process the information that arrives. They help make sure the information arrives in the first place. The Lesson: Oversight Is a Shared Process Employers ultimately have a responsibility to oversee their retirement plans, even when they hire professionals to handle much of the day-to-day work. That doesn’t mean the employer should have to become a retirement plan expert or personally track every filing deadline and compliance requirement. That’s one of the reasons experienced administration matters. A proactive provider should help keep the employer informed, identify missing information, follow up when something is outstanding, and escalate issues before a missed request becomes a missed filing—or several years of missed filings. The cost of failing to do so can extend well beyond an annual administration fee: Missed filings and potential penalties Incomplete compliance testing Corrective work Additional professional fees Delayed business transactions Uncertainty during mergers and acquisitions  By the time those costs appear, they can far exceed whatever might have been saved by choosing a lower-cost service model. That’s why retirement plan administration shouldn’t simply be viewed as paperwork. It should be viewed as an ongoing partnership in managing risk.
August 18, 2026
The Challenge A business owner came to us after receiving confusing news from their retirement plan actuary. Their Defined Benefit (Cash Balance) Plan had performed exceptionally well over several years; strong investment returns seemed to have created what’s called an overfunded Plan. While it seems like a positive name, an overfunded plan can create excessive and unexpected tax liabilities. So, their actuary recommended terminating the Plan by transferring the excess assets into the company's other Plan, a 401(k)/Profit Sharing Plan, before eventually closing both Plans, a lengthy and complicated process.
July 15, 2026
As we wrap up the second quarter of 2026, one trend continues to stand out: retirement plans are becoming increasingly specialized. Whether driven by changing regulations, unique workforce structures, or evolving business goals, employers are finding that a one-size-fits-all approach simply doesn't work. This quarter, we explored the unique retirement plan challenges facing several industries—including medical and dental practices, construction companies, architecture and design firms, wineries, and California employers navigating CalSavers requirements. We also continued our series on the hidden risks of low-quality retirement plan services, highlighting how operational complexity, fragmented accountability, and misaligned incentives can create costs that extend far beyond administrative fees. For employers still evaluating their retirement plan options, we also discussed opportunities that many business owners overlook, including the ability to establish retirement plans after filing a tax extension and potentially generate meaningful tax savings. Below is a recap of the articles we published this quarter. We hope they provide practical insights to help you reduce risk, improve plan performance, and make more informed retirement plan decisions.
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