Special Trivia Question for 6/16/2026 (After-tax 401(k) contributions and the Mega Backdoor Roth, Part II

This post mentions Form 5500-EZ in passing. It is a form that needs to be filed with the IRS when the balance of a Solo 401(k) exceeds $250,000 (or possibly as soon as a few short years after maximum contributions are made annually).

What is the penalty for not filing Form 5500-EZ?

A. $100 per month, reaching a maximum after four months ($400)
B. $250 per month, no maximum
C. $150 per week, reaching a maximum after 24 weeks ($3,600)
D. $215 per week per plan participant, no maximum
E. $250 per day, up to a maximum of $150,000

The penalty was massively increased as part of the SECURE Act, passed in 2019. One of my colleagues informed us that this generated a notice from the IRS, indicating a six-figure penalty was due.

Fortunately, there is a relief program for delinquent filers available. This reduces the penalty to $500 per year in which the form was not filed.