For high-income earners and diligent savers, maximizing tax-advantaged retirement savings is an essential strategy. Two powerful tools in the 2025 retirement planning arsenal are after-tax 401(k) contributions with rollovers to a Roth 401(k) and backdoor Roth IRA contributions. These strategies can significantly boost your retirement savings and help you grow your nest egg tax-free. Here’s how to implement these for 2025.
What Are After-Tax 401(k) Contributions?
Many employers allow employees to contribute after-tax dollars to their 401(k) plans, in addition to the standard pre-tax or direct Roth contributions. Each 401(k) plan is different though, so subject to the 401(k) plan, these after-tax contributions can be rolled over to a Roth 401(k), where they grow tax-free.
Contribution Limits for 2025
- Employee contributions (pre-tax or direct Roth): $23,500 (or $31,000 for those aged 50+ or $34,750 for those aged 60-63).
- Total 401(k) contribution limit (employee + employer + after-tax contributions): $70,000 (or $77,500 for those aged 50+ or $81,250 for those aged 60-63).
The difference between the total contribution limit and the sum of employee and employer contributions is the maximum amount you can contribute in after-tax dollars.
Example: After-Tax 401(k) Contributions in 2025
- Employee Contributions: $23,500 (pre-tax or direct Roth).
- Employer Match: $10,000.
- Total from Employee + Employer: $33,500.
- Remaining Contribution Limit: $70,000 – $33,500 = $36,500.
You can contribute $36,500 in after-tax dollars to your 401(k). By rolling these after-tax funds into a Roth 401(k), you can benefit from tax-free growth and withdrawals in retirement.
Why Roll After-Tax Contributions Into a Roth 401(k)?
- Tax-Free Growth: Once rolled over, after-tax contributions grow tax-free in the Roth account.
- Streamlined Management: Keeping funds in your 401(k) may simplify tracking and investment management.
- Avoiding Pro-Rata Rule: Direct rollovers from after-tax 401(k) contributions avoid the complexities of the pro-rata rule that applies to Roth IRA rollovers.
What Is a Backdoor Roth IRA Contribution?
A backdoor Roth IRA contribution is a strategy for high-income earners who exceed the annual Modified Adjusted Gross Income (“MAGI”) limits for direct Roth IRA contributions. This strategy is separate from the after-tax 401(k) contribution strategy and instead involves contributing to a traditional IRA (non-deductible) and then converting those funds to a Roth IRA.
Roth IRA Contribution Limits for 2025
- MAGI Limits for Direct Roth Contributions:
- Single: $165,000 (phase-out begins at $150,000).
- Married Filing Jointly: $246,000 (phase-out begins at $236,000).
- Contribution Limit: $7,000 (or $8,000 for those aged 50+).
How to Execute a Backdoor Roth IRA in 2025
- Contribute to a Traditional IRA: Make a non-deductible contribution of $7,000 (or $8,000 if 50+).
- Convert to a Roth IRA: Convert the balance to a Roth IRA, ideally shortly after funding to avoid significant taxable gains. Beware of the Pro-Rata rule if you already have a Traditional IRA. The Pro-Rata Rule taxes the percentage of the Traditional IRA relating to deductible contributions and growth/earnings that is converted to the Roth IRA. As an example, if you make a non-deductible contribution to your Traditional IRA in 2025 of $7,000, the Traditional IRA value is $100,000 after this contribution, and you then convert $10,000 from the Traditional IRA to a Roth IRA, the taxable amount will be $10,000 * ($93,000 / $100,000) = $9,300.
- Report the Conversion: File IRS Form 8606 to report the non-deductible contribution and conversion.
Example: Backdoor Roth IRA Contribution in 2025
- Income: $250,000 (exceeds direct Roth contribution limit).
- Traditional IRA Contribution: $7,000 (non-deductible).
- Roth Conversion: Immediately convert the $7,000 to a Roth IRA. If no earnings occurred before conversion, there is no taxable event.
Over time, this $7,000 grows tax-free in the Roth IRA, providing significant long-term benefits.
Maximizing Both Strategies Together
By combining after-tax 401(k) contributions with rollovers to a Roth 401(k) and backdoor Roth IRA contributions, you can maximize your retirement savings in 2025:
Example: Maximized Retirement Contributions
- Pre-Tax 401(k) Contribution: $23,500.
- Employer Match: $10,000.
- After-Tax 401(k) Contribution: $36,500 (rolled to Roth 401(k)).
- Backdoor Roth IRA: $7,000.
- Total Contributions: $77,000 into tax-advantaged accounts, $43,500 which grows tax-free in the Roth accounts, and $33,500 which grows tax-deferred in the 401(k).
Benefits of These Strategies
- Maximized Tax-Free Growth: Roth accounts allow tax-free withdrawals in retirement, providing significant savings over time.
- Diversified Tax Strategy: By contributing to both pre-tax and Roth accounts, you balance taxable and tax-free income in retirement.
- High Contribution Limits: Leveraging both strategies enables contributions well beyond the standard limits of traditional accounts.
- Flexibility: Roth accounts have no Required Minimum Distributions (RMDs), giving you greater control over distributions in retirement.
- Estate Planning: Roth accounts do not require annual RMDs for the beneficiary and can continue to grow tax free for up to 10 years after death for a Designated Beneficiary.
Things to Consider
- Pro-Rata Rule for IRAs: If you have pre-tax funds in traditional IRAs, the pro-rata rule applies when converting to a Roth IRA, potentially increasing your tax liability.
- Plan Rules: Not all 401(k) plans allow after-tax contributions or in-plan Roth rollovers. Check with your employer for availability.
- Timing: Execute backdoor Roth IRA conversions quickly to minimize taxable gains.
Final Thoughts
Maximizing after-tax 401(k) contributions and using the backdoor Roth IRA strategy in 2025 can significantly enhance your retirement savings. These strategies are especially valuable for high-income earners looking to grow their wealth in tax-advantaged accounts.
By planning carefully and working with your financial advisor at Cardinal Point, you can ensure these strategies align with your long-term financial goals and optimize your retirement savings potential.