401(k) Plan Compensation Definitions
Is Your Payroll System Using the Correct Definition of Plan Compensation? Avoiding Costly 401(k) Audit Findings and Operational Failures
The most common pitfall in benefit plan administration is using an incorrect definition of compensation for 401(k) contributions, often occurring because payroll systems are not properly synced with the plan document. To remain compliant, plan sponsors must distinguish between “gross pay” and “plan-eligible pay,” ensuring that items like bonuses, overtime, and fringe benefits are included or excluded exactly as the legal plan document dictates. Failure to follow these specific definitions constitutes an operational failure, requiring the employer to make corrective contributions—often including a 50% “missed deferral opportunity” payment plus lost earnings—to make affected employees whole.
Key Takeaways
How can I tell if my payroll system is using the correct definition of 401k compensation?
You can verify your system’s accuracy by performing a side-by-side reconciliation of every active payroll code against the specific inclusions and exclusions listed in your legal plan document’s definition of compensation.
What happens if a company fails to include bonuses in 401k contribution calculations?
If your plan document includes bonuses but your payroll system excludes them, the IRS considers this an operational failure that requires the employer to fund a corrective contribution for the missed deferral opportunity plus lost earnings.
What is the difference between gross wages and plan-eligible compensation?
While gross wages represent an employee’s total earnings, plan-eligible compensation is the specific subset of those earnings defined by your plan document as being subject to retirement deferrals and employer matching.
Understanding Gross Pay vs. Plan-Eligible Pay
One of the most frequent findings in a benefit plan audit is a mismatch between what a payroll manager considers “pay” and what the IRS-approved plan document requires. For many employers, “gross pay” is the default setting in a payroll system. However, your plan document might use a specific IRC Section 414(s) compensation definition that excludes certain types of income. If your document excludes bonuses but your payroll system calculates deferrals on a total-compensation basis, you are technically over-contributing. Conversely, if your document includes “all W-2 compensation” but your payroll system is set to ignore overtime or commissions, you are under-contributing. This gap between system settings and legal requirements is where most audit findings begin.
The Cost of “Simple” Payroll Errors
What seems like a minor administrative oversight can quickly transform into a significant financial burden. When a CPA firm discovers that a company has used an incorrect definition of compensation, the employer cannot simply “fix it moving forward.” Instead, they must perform a retirement plan operational failure correction under the IRS Employee Plans Compliance Resolution System (EPCRS). Generally, if you failed to withhold deferrals on eligible pay (like a year-end bonus), the IRS requires you to contribute a percentage of that missed amount out of the company’s pocket, not the employee’s, to compensate for the missed investment opportunity.
“The definition of compensation is the ‘silent killer’ of 401(k) compliance; even a minor mismatch between your payroll settings and your plan document can trigger expensive employer-funded corrections that accumulate with every paycheck.”
Aligning Your Systems to Avoid Tax Headaches
To prevent these issues, it is essential to perform a regular payroll and plan document reconciliation. This involves a line-by-line review of every pay code in your payroll system—ranging from car allowances to shift differentials—to ensure they map correctly to the “eligible compensation” section of your adoption agreement. Many firms find success by creating a “compensation matrix” that HR and payroll teams review annually or whenever a new pay code is created. This proactive step ensures that 401(k) plan compensation testing remains accurate and prevents the need for a mid-audit scramble to calculate multi-year corrective distributions.
Identifying Hidden Compensation Traps
There are several “hidden” areas where compensation definitions frequently trip up even the most diligent plan sponsors. These often involve non-traditional income that doesn’t feel like a standard paycheck but still carries a tax impact.
- Fringe Benefits: Items like group term life insurance premiums over $50,000 or taxable moving expenses.
- Post-Termination Pay: Whether severance or unused vacation payouts are eligible for deferrals.
- Reimbursements: Ensuring that non-taxable travel reimbursements aren’t accidentally included in the contribution base.
- Timing of Entry: Ensuring compensation is only counted from the exact date an employee becomes eligible to participate, rather than their original hire date.
Strategic Oversight and Fiduciary Duty
Ultimately, the responsibility for maintaining an accurate definition of compensation lies with the plan fiduciaries. While third-party administrators (TPAs) and payroll providers offer excellent tools, they only process the data they are given. As a plan sponsor, your fiduciary duty includes ensuring the data flow between these entities is seamless and accurate. By conducting a periodic internal control review for benefit plans, you can identify these discrepancies before they become a formal audit finding. This not only saves the company money in potential penalties and corrective contributions but also maintains the tax-qualified status of the plan for all participants.
Disclaimer: This article provides general information and should not be considered professional financial or tax advice. Please consult with a qualified CPA or financial advisor for guidance specific to your individual business needs.
Questions?
Jackie leverages her experience in audit, review, and compilation services across multiple industries to serve clients, including those requiring specialized employee benefit plan audits. She applies her audit skills to a variety of engagements, encompassing many of the firm’s client engagements since joining the firm in 2019, ensuring compliance and financial accuracy across diverse sectors, including employee benefit plans.