Non-Discrimination Testing in 401(k) Plans: Ensuring Compliance and Avoiding Corrections

Brief Overview of 401(k) Plans and Their Significance

401(k) plans have become one of the most popular and beneficial retirement savings vehicles in the United States.

Originating from a provision in the Internal Revenue Code, these employer-sponsored plans allow employees to save a portion of their earnings in a tax-deferred account.

The funds in these accounts, often complemented by employer contributions, are invested with the goal of accumulating wealth that can support individuals in their retirement years.

The significance of 401(k) plans cannot be overstated. For many, they represent a primary source of retirement income.

Beyond individual benefits, they also serve as an attractive perk for businesses aiming to recruit and retain quality talent.

In a world where traditional pension plans are dwindling, the role of the 401(k) in ensuring a financially secure retirement has grown exponentially.

The Need for Non-Discrimination Testing in 401(k) Plans

While 401(k) plans offer numerous advantages, they also come with certain responsibilities for the sponsoring employers. At the heart of these responsibilities lies the principle of fairness.

The U.S. government has a vested interest in ensuring that 401(k) plans do not disproportionately favor higher-earning employees over their lower-paid counterparts. This is where non-discrimination testing enters the picture.

Non-discrimination testing is a set of mandatory tests carried out annually to ensure that the contributions made to 401(k) plans by and on behalf of highly compensated employees (HCEs) are proportional to those made for non-highly compensated employees (NHCEs).

These tests ensure that the benefits of tax-deferred savings in a 401(k) are equitably distributed among all employees, irrespective of their earnings or position within the company.

Failure to comply or pass these tests can lead to severe financial penalties and administrative headaches for businesses.

But beyond compliance, these tests embody the very essence of what 401(k) plans should represent: a fair and equal opportunity for all employees to secure their financial future.

In the subsequent sections, we'll delve deeper into the mechanics, importance, and practical aspects of non-discrimination testing, providing plan sponsors with a comprehensive guide to navigate this essential aspect of 401(k) plan administration.

Understanding Non-Discrimination in 401(k) Plans

Definition of Non-Discrimination in the Context of 401(k) Plans

At its core, non-discrimination in the realm of 401(k) plans revolves around the idea that all employees, regardless of their compensation or position within a company, should have equitable access to the benefits offered by these retirement savings programs.

In more technical terms, non-discrimination tests are designed to ensure that the contributions made to a 401(k) by or on behalf of HCEs don't substantially outweigh those made for NHCEs.

The Internal Revenue Service (IRS) and the Department of Labor (DOL) have established specific guidelines and tests to ensure that these plans do not inadvertently or deliberately favor the higher earners over the rest of the workforce.

Importance of Fair Treatment Between Highly Compensated Employees (HCEs) and Non-Highly Compensated Employees (NHCEs)

  1. Promoting Retirement Savings for All: One of the main reasons 401(k) plans enjoy tax benefits is to encourage retirement savings among the general workforce. If the advantages of these plans only accrue to the higher-paid employees, it would counteract this objective.
  2. Ensuring Equitable Benefits: Without non-discrimination testing, there's a risk that employers might structure their plans in ways that primarily benefit HCEs, either through higher matching contributions or by setting up barriers that prevent NHCEs from participating.
  3. Avoiding Penalties and Compliance Issues: The IRS has established penalties for plans that fail non-discrimination tests. By ensuring a fair balance between HCE and NHCE contributions, businesses can avoid these penalties and the associated financial and reputational costs.
  4. Enhancing Employee Morale and Trust: An equitable 401(k) plan can boost morale among employees. When workers believe they are receiving fair treatment, it can lead to increased trust in management and higher overall job satisfaction.
  5. Maintaining Tax-Advantaged Status: Failing non-discrimination tests can jeopardize the tax-advantaged status of a 401(k) plan. This would not only result in financial implications but could also diminish the attractiveness of the plan for employees.

In conclusion, non-discrimination in 401(k) plans isn't just a regulatory requirement. It's a reflection of the broader principle that retirement security should be accessible to all, regardless of their position or pay grade.

Ensuring that 401(k) contributions are balanced between HCEs and NHCEs helps to maintain the integrity of these plans and their role in promoting financial security for all workers.

Legal Framework and Regulatory Requirements

Overview of the Employee Retirement Income Security Act (ERISA)

The Employee Retirement Income Security Act (ERISA) of 1974 is a federal law that sets minimum standards for most voluntarily established retirement and health plans in private industry. Its primary aim is to provide protection for individuals in these plans.

  • Purpose: ERISA protects the retirement assets of Americans by implementing rules that qualified plans must follow to ensure plan fiduciaries do not misuse plan assets.
  • Coverage: While ERISA covers both retirement (e.g., 401(k) plans) and health plans, its provisions concerning non-discrimination primarily affect retirement plans.
  • Mandatory Disclosures: Under ERISA, plan administrators are required to provide plan participants with important information about plan features and funding. This includes details about the plan's benefits and how it is operated.
  • Fiduciary Responsibilities: ERISA defines the standards of conduct for those who manage an employee benefit plan and its assets, known as fiduciaries. This includes ensuring that the plan is not discriminatory and complies with relevant non-discrimination tests.
  • Claim Process: The law ensures that participants have the right to sue for benefits and breaches of fiduciary duty if the plan is not managed in compliance with the regulations.

Role of the Internal Revenue Service (IRS) and Department of Labor (DOL) in Enforcement

  1. Internal Revenue Service (IRS)
  • Plan Qualification: The IRS is primarily responsible for determining whether a 401(k) plan meets the tax qualification rules. If a plan fails to meet these rules, including non-discrimination standards, it risks losing its tax-qualified status.
  • Testing and Audits: The IRS conducts tests and audits on 401(k) plans to ensure they meet the nondiscrimination requirements. Plans that fail these tests may face penalties or be required to take corrective actions.
  • Guidance and Regulations: The IRS provides detailed guidelines on various aspects of 401(k) plans, including how non-discrimination tests should be carried out and what constitutes an HCE.
  1. Department of Labor (DOL)
  • Protection of Plan Participants: While the IRS focuses on the tax aspects of 401(k) plans, the DOL is more concerned with the protection of plan participants. Its role is to ensure that employees receive the benefits they're promised and that their rights under ERISA are upheld.
  • ERISA Enforcement: The DOL enforces the provisions of ERISA, including those related to non-discrimination. They conduct investigations, answer inquiries, and take corrective actions when necessary.
  • Educational Initiatives: The DOL provides resources and educational materials to help employers, plan administrators, and the public understand their responsibilities and rights under ERISA.

In summary, while both the IRS and DOL play pivotal roles in the enforcement of 401(k) plan regulations, they have distinct areas of focus.

The IRS emphasizes the tax implications and qualification of the plan, while the DOL ensures the protection and rights of plan participants. Together, they ensure the integrity and fairness of 401(k) plans.

Core Non-Discrimination Tests

Actual Deferral Percentage (ADP) Test

Overview and Purpose

The ADP test is designed to ensure that the amount of elective deferrals by Highly Compensated Employees (HCEs) is proportional to those made by Non-Highly Compensated Employees (NHCEs). In essence, it ensures that HCEs aren't contributing to the 401(k) plan at significantly higher rates than NHCEs.

Calculation and Interpretation

  • Determine the deferral rate for each eligible employee: This is calculated by dividing the employee's elective deferrals (excluding catch-up contributions for those age 50 or older) by the employee's compensation.
  • Average the rates: Calculate the average of these rates for both HCEs and NHCEs separately.
  • Comparison: Compare the average deferral rate of HCEs to that of NHCEs. Generally, the HCE group's average deferral rate must not exceed the NHCE group's average by more than a specified percentage.

Actual Contribution Percentage (ACP) Test

Overview and Purpose

Similar to the ADP test, the ACP test ensures fairness, but it focuses on employer-matching contributions and employee after-tax contributions. It checks if HCEs are receiving employer contributions in proportion to those received by NHCEs.

Calculation and Interpretation

  • Determine the contribution rate for each eligible employee: This is calculated by dividing the total of an employee's matching and after-tax contributions by the employee's compensation.
  • Average the rates: Calculate the average of these rates for both HCEs and NHCEs separately.
  • Comparison: Compare the average contribution rate of HCEs to that of NHCEs. The HCE group's average contribution rate should not exceed the NHCE group's average by more than a specific threshold.

Top Heavy Test

Definition and Significance

A 401(k) plan is considered “top-heavy” if, at the end of the previous plan year, the total value of the plan assets of “key employees” exceeds 60% of the total assets of the plan. “Key employees” include officers, owners, and their family members. The test ensures that the majority of the plan's benefits don't just go to a small group of key employees.

Determination and Remedies

  • Determination: Calculate the total account balances of key employees and compare them to the total account balances of all employees. If the key employee total exceeds 60%, the plan is top-heavy for the following year.
  • Remedies: If a plan is found to be top-heavy, the employer may be required to make minimum contributions to the accounts of NHCEs, usually 3% of each NHCE's compensation, ensuring that they are provided a minimum benefit.

In essence, these tests are regulatory mechanisms to ensure that 401(k) plans are operated in a manner that is fair and benefits a broad cross-section of employees, not just a select few at the top.

Additional Compliance Tests

Coverage Test

Overview and Purpose

The Coverage Test ensures that a 401(k) plan does not disproportionately benefit Highly Compensated Employees (HCEs) by covering a sufficient percentage of Non-Highly Compensated Employees (NHCEs). This is a key step to make sure that the plan doesn't just serve the top earners but provides benefits to a broader employee base.

Calculation and Interpretation

  • Ratio Percentage Test: Determine the ratio of NHCEs benefiting from the plan to HCEs benefiting. The ratio should be at least 70%.
  • Average Benefits Test: Compare the average benefits provided to HCEs and NHCEs. NHCEs' benefits should be at least 70% of HCEs' benefits when averaged.

If a plan fails the Ratio Percentage Test, it might still pass using the more complex Average Benefits Test.

Limitations on Contributions and Benefits

Overview and Purpose

To ensure that 401(k) plans do not disproportionately favor HCEs, there are limits placed on the amount of contributions and benefits that can be provided to any single participant.


  • Contribution Limits: For a given year, there's a set limit on the total amount an employee can contribute to their 401(k) as elective deferrals. The IRS typically updates this amount annually.
  • Annual Benefits and Compensation Limit: The IRS also sets an annual limit on the total benefits an employee can accrue in a defined benefit plan and an annual limit on the compensation that can be considered for plan contributions and benefits.

Compensation Definition and Testing

Overview and Purpose

Compensation is a fundamental concept in 401(k) plans, affecting contributions, distributions, and testing. Therefore, its definition should be clear, consistent, and compliant with regulations.

Key Considerations

  • Definition: The plan document should define what counts as compensation. This could be W-2 wages, gross compensation, or another definition, but it must be consistent.
  • Exclusions: Some forms of compensation, like bonuses or overtime, might be excluded. If so, it's essential to ensure this doesn't lead to discrimination in favor of HCEs.
  • Testing: Regular testing should be conducted to ensure that the compensation definition used is not skewing benefits disproportionately towards HCEs.

It's crucial for plan sponsors to be well-versed in these additional compliance tests. They not only ensure fairness and adherence to regulations but also protect the plan from potential legal liabilities and financial penalties.

Potential Consequences of Failing Tests

IRS Penalties

Overview and Purpose

The IRS imposes penalties on 401(k) plan sponsors that don't adhere to non-discrimination rules. The objective is to ensure fairness across all employees and avoid undue favoring of HCEs.

Common Penalties

  • Monetary Fines: Depending on the severity and duration of the non-compliance, the IRS can levy significant fines on the plan sponsor. These fines are meant to discourage non-compliance and can increase based on the size of the 401(k) plan and the number of affected participants.
  • Loss of Tax Benefits: One of the significant advantages of 401(k) plans is their tax benefits. If a plan is deemed non-compliant, those tax benefits can be revoked, impacting both the employer and employees.

Mandatory Corrective Actions

Overview and Purpose

If a plan fails non-discrimination tests, corrective actions must be taken to restore its compliant status. These corrections are meant to rectify the discrimination and ensure the plan benefits all eligible employees fairly.

Common Corrective Actions

  • Refunding Excess Contributions: For plans that exceed the contribution limits set for HCEs, the excess amounts might need to be refunded to the HCEs to ensure compliance.
  • Employer Contributions: In some cases, the employer might need to make additional contributions to the NHCEs' accounts to balance the scales and pass the nondiscrimination tests.
  • Plan Re-Design: In extreme cases, the entire plan might need a re-design to ensure future compliance.

Impact on Plan Participants and Beneficiaries


The consequences of failing non-discrimination tests can reverberate beyond just the plan sponsor. They can also have implications for the plan participants and their beneficiaries.

Key Impacts

  • Refunds and Tax Implications: Refunded contributions to HCEs can result in unexpected tax liabilities, as these refunds are generally taxable.
  • Change in Benefits: If the plan requires a re-design or the employer needs to make corrective distributions, it might change the benefits participants were expecting.
  • Loss of Trust: Repeated failures can erode trust between employees and employers, leading to decreased participation in the plan or increased skepticism about its management.

It's evident that non-compliance with non-discrimination rules can have widespread consequences.

Beyond the immediate financial implications, it can impact employee morale, trust, and the overall health of the 401(k) plan. As such, continuous monitoring, understanding the regulations, and acting proactively are crucial for any plan sponsor.

Strategies to Avoid Test Failures

Safe Harbor 401(k) Plans


Safe harbor 401(k) plans are designed to automatically satisfy certain non-discrimination tests, including the ADP and ACP tests, given they meet specific contribution, vesting, and notice requirements.

Key Features

  • Mandatory Employer Contributions: Employers are required to make either matching or non-elective contributions to their employees' accounts.
  • Immediate Vesting: Contributions made under safe harbor provisions must be 100% vested immediately.
  • Annual Notice Requirements: Employees must receive a notice, typically annually, detailing their rights and obligations under the plan.

Automatic Enrollment Provisions


By automatically enrolling eligible employees into the 401(k) plan, employers can boost participation rates, especially among NHCEs, which can help in passing the nondiscrimination tests.

Key Features

  • Default Contribution Rates: Employees are enrolled at a predefined contribution rate unless they opt out or choose a different rate.
  • Escalation: Some automatic enrollment designs increase the default contribution rate annually, helping boost savings rates over time.

Matching or Non-Elective Contributions


Providing matching contributions or making non-elective contributions can help balance the contributions made by HCEs and NHCEs, ensuring that the plan meets non-discrimination requirements.

Key Features

  • Matching Contributions: Employers match a portion of the employees' contributions, often up to a certain percentage of their salary.
  • Non-Elective Contributions: These are contributions made by the employer regardless of the employee's contribution amount, typically a fixed percentage of the employee's salary.

Regular Internal Reviews and Audits


Periodic internal reviews and audits help identify potential issues before they become major problems, ensuring that the plan remains compliant.

Key Features

  • Monitoring Participation Rates: Regularly tracking participation by both HCEs and NHCEs can help identify potential disparities early on.
  • Checking Contribution Amounts: By monitoring contribution amounts and comparing them to set limits, employers can take corrective action if limits are approached or exceeded.
  • Employing Third-Party Auditors: Engaging external experts can provide an unbiased view of the plan's compliance status, and they can offer actionable recommendations to ensure ongoing adherence to regulations.

By proactively implementing these strategies, employers can significantly reduce the risk of failing non-discrimination tests, ensuring that their 401(k) plans remain compliant and beneficial for all employees.

Corrective Actions for Failed Tests

Methods to Correct ADP/ACP Failures


If a 401(k) plan fails the ADP (Actual Deferral Percentage) or ACP (Actual Contribution Percentage) tests, the plan sponsor must take corrective actions within a specific timeframe to maintain the plan's tax-qualified status.

Key Approaches

  • Re-distribute Excess Contributions: Return excess contributions to HCEs to reduce their average deferral or contribution percentages.
  • Increase NHCE Contributions: Increase contributions to NHCEs to raise their average deferral or contribution percentages, bringing them closer to the HCE percentages and satisfying the tests.

Refunding Excess Contributions to HCEs


This method involves returning a portion of the HCEs' contributions to reduce their average contribution rates, bringing them in line with permissible levels relative to NHCEs.

Process Steps

  • Identify Excess Amounts: Calculate the amount by which the HCE contributions exceed allowable limits based on the test results.
  • Timely Refund: Return the excess contributions to the affected HCEs within 2½ months after the end of the plan year to avoid a 10% excise tax. If missed, the deadline can be extended to 12 months, but the excise tax applies.
  • Tax Implications: Refunded amounts are generally taxable to the HCE in the year of distribution.

Making Qualified Nonelective Contributions (QNECs) to NHCEs


Instead of taking money back from HCEs, plan sponsors can choose to make additional contributions to NHCEs, known as QNECs, to correct failed ADP/ACP tests.

Key Features

  • Fully Vested: QNECs must be 100% vested immediately.
  • Calculations: The amount of QNEC needed is determined by the shortfall in the ADP/ACP tests and is allocated to NHCEs based on their compensation.
  • Flexibility: QNECs can be used in combination with other corrective methods, such as returning excess contributions to HCEs.

In summary, while failing non-discrimination tests can be a concern for 401(k) plan sponsors, there are multiple correction methods available.

The best approach depends on the specific circumstances of the plan and the preferences of the plan sponsor.

It's essential to act promptly and consult with a retirement plan expert to ensure compliance and the continued tax-favored status of the plan.

Best Practices for Plan Sponsors

Educating Employees About the Importance of Participation


One of the most effective ways to ensure non-discrimination compliance is by boosting participation rates among all employees, particularly NHCEs.


  • Regular Workshops: Host educational sessions detailing the benefits of 401(k) participation, potential tax savings, and the power of compound interest.
  • Informational Materials: Distribute brochures, flyers, and digital content breaking down complex financial terms into digestible insights.
  • Personalized Consultations: Offer one-on-one financial consultations where employees can discuss their retirement goals and understand the benefits of saving early.

Periodic Reviews of Plan Design and Features


Periodic assessment ensures the plan remains competitive, meets employees' needs, and stays compliant with non-discrimination rules.

Action Steps

  • Annual Reviews: Analyze participation rates, contribution amounts, and overall plan performance yearly.
  • Benchmarking: Compare your plan's features and participation rates to industry standards or similar-sized companies.
  • Feedback Loop: Survey employees to gather feedback on plan features, and make adjustments based on their preferences and needs.

Working closely with Plan Administrators and Third-Party Service Providers


External experts can provide crucial insights, manage technical aspects of the plan, and assist with compliance.

Key Collaborations

  • Plan Administrators: Regularly communicate with them to ensure plan operations align with established policies and regulations.
  • Consultants & Advisers: Engage financial experts to guide plan design, investment options, and compliance strategies.
  • Legal Counsel: Ensure all plan documentation and operations adhere to current laws and regulations.

Leveraging Technology and Software for Compliance Monitoring


In today's digital age, several tools can simplify compliance processes, provide analytics, and ensure accuracy.

Utilizing Technology

  • Compliance Software: Use specialized software that runs non-discrimination tests automatically and provides real-time insights.
  • Alert Systems: Implement systems that notify administrators of potential compliance issues or when key thresholds are nearing.
  • Data Analytics: Utilize analytics to predict participation trends, spot irregularities, and model potential plan changes.

By adhering to these best practices, plan sponsors can proactively manage their 401(k) plans, foster higher participation rates, and minimize the risk of non-compliance, ensuring a robust and beneficial plan for all employees.

Real-World Case Studies

Case Study 1: Tech Startup's Rapid Growth Leads to Testing Failures


A burgeoning tech startup experienced a rapid influx of new hires, many of whom were highly compensated. This skewed the balance between HCEs and NHCEs.


Their 401(k) plan, originally designed for a smaller and less diversified salary scale, began to consistently fail the ADP and ACP tests.

Actions Taken

  • Refunded excess contributions to HCEs for immediate compliance.
  • Engaged a third-party plan administrator to redesign the plan, emphasizing better balance and compliance.
  • Introduced a safe harbor 401(k) plan with automatic enrollment to ensure better participation from all employees.


With these changes, the company successfully passed non-discrimination tests in subsequent years and fostered a culture of retirement readiness.

Lessons Learned

Rapid company growth can lead to unexpected 401(k) compliance challenges, requiring proactive plan adjustments.

Case Study 2: Manufacturing Firm Overlooks Top Heavy Rules


A well-established manufacturing firm with a stable workforce had a significant number of long-tenured employees with substantial 401(k) balances.


The firm neglected the Top Heavy Test, finding that key employees held more than 60% of total plan assets.

Actions Taken

  • The firm made mandatory minimum contributions to NHCEs to correct the top-heavy imbalance.
  • Revisited and adjusted their contribution matching structure to avoid such imbalances in the future.
  • Offered financial education workshops, encouraging more NHCEs to participate and contribute actively to the 401(k) plan.


Corrective actions ensured immediate compliance. Enhanced education and engagement led to higher NHCE participation, reducing top-heavy concerns.

Lessons Learned

It's essential to monitor all facets of 401(k) compliance, especially in firms with long-tenured employees.

Case Study 3: Retail Chain Faces Coverage Test Hurdles


A national retail chain with multiple locations had variable participation rates in their 401(k) across different stores.


Several stores failed the Coverage Test, as not enough NHCEs were benefiting from the plan compared to HCEs.

Actions Taken

  • Instituted an aggressive communication campaign highlighting the benefits of the 401(k) to NHCEs.
  • Simplified the enrollment process, making it easier for employees to join.
  • Introduced incentives, such as a raffle for new enrollees, to boost participation.


The next year saw a significant increase in NHCE participation, ensuring compliance with the Coverage Test.

Lessons Learned

Engaging, educating, and simplifying processes can significantly influence NHCE participation in 401(k) plans.

These case studies emphasize the multifaceted nature of 401(k) compliance and the need for vigilance, adaptability, and proactive management to ensure fair and beneficial plans for all employees.


In the realm of 401(k) plans, non-discrimination testing emerges not merely as a regulatory hurdle but as a cornerstone that ensures equity and fairness.

At its core, the tests are designed to ensure that every employee, regardless of their compensation level, is given equitable access and benefits from the company's retirement plan.

Ensuring compliance is not just about avoiding penalties. It underscores a company's commitment to all its employees, valuing the contributions of both the boardroom and the breakroom equally.

By understanding and actively working within the regulatory framework, companies can not only avoid the pitfalls of non-compliance but can also promote a more inclusive, supportive, and forward-thinking work culture.

Yet, like most regulatory requirements, non-discrimination testing can pose challenges. Companies must be proactive, consistently reviewing their plans and staying informed about any legislative changes that might impact them.

Best practices involve not only keeping abreast of the tests themselves but also implementing measures that inherently promote broader participation and contribution balance.

This might include educational programs, automatic enrollment mechanisms, or even rethinking the 401(k) plan design as the workforce evolves.

In closing, while navigating the nuances of 401(k) nondiscrimination testing might seem intricate, the underlying message is straightforward: A fair retirement plan benefits everyone.

Companies that prioritize this equity not only stand in good stead with regulators but also bolster their reputation as employers that genuinely value and support their workforce.