The HR Team's Guide to 401(k) Compliance

Nondiscrimination testing, Form 5500, DOL audit triggers, and a 2026 compliance calendar

Running a 401(k) plan means running a federally regulated financial vehicle. ERISA, the IRS, and the Department of Labor impose specific obligations on every employer that sponsors one, from annual testing requirements to filing deadlines to participant disclosure rules. Most of these obligations are manageable. Few are intuitive for an HR professional managing a plan alongside ten other priorities.

What's inside

1. The Compliance Framework: What ERISA Requires

2. Nondiscrimination Testing: ADP, ACP, and Top-Heavy

3. What Happens When a Plan Fails Testing

4. Form 5500: Who Files, What's Required, When It's Due

5. 2026 Compliance Calendar

6. DOL Audit Triggers and How to Prepare

7. HR Team Compliance Checklist

8. Conclusion