Updated 2026-03-19

10 401(k) Investment Mistakes That Cost You Thousands

The most common 401(k) investing mistakes and how to avoid them. From skipping the match to panic selling, with the dollar cost of each error.

What You Will Learn

This guide covers everything you need to know about 10 401(k) investment mistakes that cost you thousands. We break down the rules, compare your options, and provide tools to help you make informed decisions about your retirement savings.

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Pavlo Pyskunov

Pavlo Pyskunov

Managing Director & Investment Fund Director

Pavlo Pyskunov analyzes employer-sponsored retirement plans using IRS publications and DOL Form 5500 filings, helping workers maximize their 401(k) savings through data-driven guidance.

Last updated: 2026-03-19

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