Updated 2026-04-21

After-Tax 401(k) Contributions: How the Mega Backdoor Roth Works

After-tax 401(k) contributions explained. How they differ from pre-tax and Roth, the mega backdoor Roth strategy, and the 2026 total contribution limit.

Key Takeaways

2026 Quick Reference

$24,500
2026 Deferral Limit
$72,000
Total 415(c) Limit
59½
Penalty-Free Age
73
RMD Start Age

Related Guides

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: 2026-04-21

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