Strategy Snapshot
High earners are phased out of direct Roth IRA contributions, but two legal workarounds remain. The backdoor Roth converts a nondeductible IRA contribution to Roth. The mega backdoor Roth uses after-tax 401(k) contributions to move far more. The backdoor's main hazard is the pro-rata rule on existing pre-tax IRA balances.
Contribute to a nondeductible traditional IRA (up to $7,000, or $8,000 if 50+), then convert it to Roth. The income limits on Roth contributions do not apply to conversions.
If your 401(k) allows after-tax contributions and in-plan conversions, you can funnel tens of thousands more into Roth each year, up to the overall plan limit.
The pro-rata rule. If you hold other pre-tax IRA money, your backdoor conversion is partly taxable. Rolling pre-tax IRAs into a 401(k) first usually fixes it.
Roth accounts are the most desirable place to build wealth, tax-free growth and tax-free withdrawals in retirement, which is exactly why the IRS phases high earners out of contributing to them directly. The catch is that the phase-out applies to contributions, not conversions, and that gap is the entire basis for two legal strategies that let high earners get Roth money in anyway.
There is an income limit to contribute to a Roth. There is no income limit to convert to a Roth. The backdoor strategies simply walk through the second door.The loophole, plainly
Who Gets Phased Out
For 2025, the ability to contribute directly to a Roth IRA phases out at modified AGI of roughly $150,000 to $165,000 (single) and $236,000 to $246,000 (married filing jointly). Above the top of the range, direct Roth contributions are off the table, and that is where the backdoor begins.
The Backdoor Roth, Step by Step
- Contribute to a traditional IRA, nondeductible, up to
$7,000(or$8,000if age 50+) for 2025. There is no income limit to make a nondeductible contribution. - Convert that traditional IRA to a Roth IRA, ideally soon after, before it generates much earnings.
- File Form 8606 to report the nondeductible basis and the conversion, so you are not taxed twice.
Because you already paid tax on the contribution (it was nondeductible), converting it creates little or no additional tax, just the small earnings between contribution and conversion.
The Pro-Rata Rule: The Mistake That Ruins It
Here is what catches people. When you convert, the IRS does not let you cherry-pick your after-tax dollars. It aggregates all your traditional, SEP, and SIMPLE IRAs and treats your conversion as coming proportionally from pre-tax and after-tax money.
The fix: roll your pre-tax IRA balances into an employer 401(k) (if the plan accepts roll-ins) before doing the backdoor. The 401(k) is not part of the pro-rata calculation, so once your IRAs hold only the nondeductible contribution, the conversion is clean. Plan this in the same calendar year, the pro-rata test looks at your IRA balances on December 31.
The Mega Backdoor Roth
The mega backdoor is the high-octane version, and it lives inside your 401(k) rather than an IRA. It relies on a third contribution bucket most people never use: after-tax (non-Roth) contributions.
| 401(k) bucket | 2025 limit |
|---|---|
| Your elective deferral (pre-tax or Roth) | $23,500 ($31,000 if 50+) |
| Employer match | Varies |
| After-tax (non-Roth) contributions | Whatever fits under the overall limit |
| Overall combined limit | $70,000 ($77,500 if 50+) |
If your plan allows after-tax contributions, you can fill the gap between your deferral plus match and the $70,000 overall limit with after-tax dollars, then convert those to Roth (via in-plan Roth conversion or an in-service rollover to a Roth IRA). That can move tens of thousands of additional dollars into Roth in a single year.
Coordinating With the Rest of Your Plan
For self-employed readers, these strategies sit alongside the Solo 401(k) vs. SEP-IRA decision, and the Roth feature of a Solo 401(k) can make the mega backdoor accessible to a one-person business. The order of operations matters: a SEP-IRA, for instance, creates exactly the kind of pre-tax IRA balance that triggers the pro-rata rule on a backdoor Roth.
When to Seek Help
A clean backdoor Roth, where you have no other IRA balances, is something a careful person can execute and report correctly. The time to get advice is when you have existing pre-tax IRA money (the pro-rata fix has to be sequenced right), when you want to set up a mega backdoor in your own business’s plan, or when you are coordinating Roth strategy with a SEP, Solo 401(k), and your overall retirement plan. The dollars these strategies move are large and compound tax-free for decades, which makes getting the mechanics right unusually valuable.
Last updated: 2026