My understanding is that $66,000 is the maximum allowable contribution to your 401K account, combining both your personal and employer contributions. Assuming your annual salary is $500,000, plus a $500,000 bonus, and your company offers a 5% match on eligible income. While the calculated amount would be $75,000 ($22,500 + 5% of $1,000,000), the total allowed annual contribution remains capped at $66,000. Please note that the information provided above is not intended as financial advice!!!