If you make too much money to contribute to a Roth IRA, there's a legal workaround that a growing number of six-figure earners are using to shelter tens of thousands of dollars a year from future taxes.
It's called the mega backdoor Roth, and despite the name, there's nothing shady about it.
In 2025, the total amount you and your employer can put into a workplace plan is $70,000, or $77,500 if you're 50 or older.
But if your plan allows it, you can fill the gap beyond the standard $23,500 employee contribution with after-tax dollars, then convert that money into a Roth account.
That gap can be more than $40,000 a year for some workers, especially those whose employers kick in generous matching contributions.
Once converted, the money grows tax-free and comes out tax-free in retirement, even though you blew past the income limits that normally block high earners from Roth accounts.
The catch is that your employer's plan has to permit two specific features.
First, it must allow after-tax contributions, which is different from the pre-tax and Roth options most people know.
Second, it has to let you either convert those after-tax dollars to a Roth within the plan or roll them into an outside Roth IRA.
Many plans offer one or both, but plenty still don't.
Even if your plan qualifies, the mechanics can trip you up.
You'll typically owe income tax on any earnings that pile up before you convert, so speed matters.
Some plans let you convert automatically after every paycheck, which keeps that taxable slice tiny.
Others make you call or click through a request each time, and delays can create an unwelcome tax bill.
The after-tax dollars you contribute don't get the same tax deduction as traditional 401(k) money, so you're funding this with cash you've already paid taxes on.
That's the trade-off: no break now, tax-free growth and withdrawals later.
For someone in a high tax bracket today who expects rising rates or big retirement spending, that deal can look pretty good.
For someone in a lower bracket, it's often not worth the hassle.
One more thing to check: not every plan's after-tax option plays nice with the annual testing rules that govern 401(k)s.
Highly compensated employees sometimes get refunds that shrink what they can actually contribute, so it's worth asking your HR department or plan administrator for the fine print before you bank on hitting the max.
The mega backdoor Roth isn't for everyone, and it won't rescue a retirement that's already behind.
But for disciplined savers who've maxed out every other tax-advantaged account, it's one of the few remaining ways to move serious money into tax-free territory while the rules still allow it.
Our take: this strategy rewards people who read their plan documents and ask uncomfortable questions of their HR department.
If you're a high earner with a decent 401(k), it's worth a 20-minute call to find out whether your plan supports it.
Final Thoughts
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