Unlock Secure 401(k) Compliance This Year
- Michelle Marsh
- 16 hours ago
- 4 min read
Managing a 401(k) plan involves more than just facilitating employee savings; it requires careful attention to annual compliance testing. Navigating these requirements can raise questions and concerns, from understanding complex regulations to addressing unexpected test results.
With the right approach, plan sponsors can turn this process into an opportunity to strengthen their retirement plan and support their employees’ financial futures. RPCSI’s experienced team stands ready to guide sponsors through each step, making sure compliance is not just a task, but a valuable part of plan management.
Why 401(k) Compliance Testing Matters
Compliance testing exists to confirm that your plan benefits rank-and-file employees in a way that’s comparable to highly compensated employees (HCEs). If results trend the wrong way, the fix can be expensive and time sensitive.
Testing also gives you early signals about plan health. Low participation, misclassified employees, and payroll data problems often show up first in testing results.
Strong testing practices help you:
Maintain the plan’s tax-qualified status
Avoid penalties and last-minute corrections
Support better participation and employee outcomes
Reduce reputational and operational risk
The Main Tests Plan Sponsors Face Each Year
Most annual testing falls into three buckets: nondiscrimination testing, top-heavy testing, and contribution limit monitoring. While the calculations are technical, most failures trace back to the same operational causes: participation patterns and data quality.
1. Nondiscrimination Testing
Nondiscrimination testing is the IRS’s way of confirming your 401(k) plan doesn’t mainly benefit owners and higher-paid employees. In simple terms, the IRS compares how much Highly Compensated Employees (HCEs) benefit from the plan versus Non-Highly Compensated Employees (NHCEs). If the gap is too large, the plan can “fail” the test and needs a correction.
HCE status is usually based on prior year pay (plus certain ownership rules), so it’s important to confirm who is counted as an HCE each year before running testing.
Common nondiscrimination tests include:
Coverage (IRC 410(b)): confirms enough NHCEs are benefiting
ADP: compares average salary deferrals for HCEs vs. NHCEs
ACP: compares employer match and after-tax contributions
401(a)(4): broader review of benefits/allocations for fairness
2. Top-Heavy Testing
A 401(k) plan is considered top-heavy when “key employees” (typically certain owners and highly paid leaders) hold more than 60% of the total value of all plan accounts. This usually happens in owner-heavy companies or when rank-and-file participation is low, causing most of the plan’s balances to sit with a small group.
If the plan is top-heavy for the year, the employer generally must make a minimum contribution for eligible non-key employees, often 3% of pay, even if those employees did not contribute to the plan themselves. (Exact eligibility and calculation details depend on your plan document.)
Best practices:
Confirm key employee status annually (especially after ownership, leadership, or compensation changes).
Monitor participation and deferrals during the year, since low NHCE participation increases top-heavy risk.
Ask your RPC for a mid-year check or projection if your plan has trended top-heavy before.
Keep payroll/census data clean (compensation, hire/term dates, and eligibility), so testing results are accurate.
Consider plan features that boost broader participation, like auto-enrollment and education, to reduce concentration over time.
Budget ahead for the possibility of a minimum contribution if your company is owner-heavy or has a small employee base.
3. Contribution Limit Monitoring
Even if your plan passes nondiscrimination and top-heavy testing, it still must follow separate IRS annual contribution limits. Limit issues often happen due to bonuses, mid-year payroll changes, late contribution uploads, or employees participating in multiple plans within the same year.
For 2026, the maximum employee elective deferral for 401(k), 403(b), and most 457 plans is $24,500. Total combined contributions (employee and employer) cannot exceed $72,000 for 2026, or $80,000 including standard catch-up contributions.
Operational areas to watch:
Elective deferral limits (pre-tax + Roth combined), including catch-up rules
Total annual additions limits (employee + employer contributions, including match/profit sharing/forfeitures)
Payroll coding and timing, especially around bonuses and year-end true ups
Common Pitfalls (and How to Avoid Them)
Most compliance problems are preventable with a few consistent process checks. The goal is to avoid discovering issues only after the plan year is over.
The most common pitfalls:
Misclassified HCEs or key employees after ownership/structure changes
Missed eligibility dates or improper exclusions
Inaccurate census data (compensation, hours, hire/termination dates)
Low NHCE engagement in voluntary enrollment plans
Prevention strategies that work:
Automatic enrollment and (optional) automatic escalation
Annual eligibility and payroll audits
Mid-year “testing forecast” check-ins with your RPC
Employee education to increase NHCE participation
How RPCSI Helps Sponsors Stay Ahead
Compliance is easier when you’re not reacting at year end. RPCSI helps sponsors spot risk early, keep data clean, and choose correction methods that align with plan goals.
If you want fewer surprises and a smoother year-end process, a proactive compliance review is the fastest way to get there.
Contact RPCSI for a plan compliance checkup or visit our services page to see how we support plan sponsors year-round.
