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What's on the Table
$1.6 million. That is roughly twelve times the $132,300 average 401(k) balance Fidelity reported for the third quarter of 2024 — and it is the balance that lands a saver in the neighborhood of the top 1% of retirement accounts, per that same Fidelity data. It is also, awkwardly, the balance that makes a person ineligible to do the single simplest thing in retirement saving: write a check to a Roth IRA.
According to Google News, 24/7 Wall St. published a piece on August 3, 2026 outlining three routes high earners can still take to build Roth assets despite income limits — the backdoor Roth IRA, the mega backdoor Roth, and straight Roth conversions. The part worth arguing about is not that all three exist. It is that they are not remotely equal, and the ranking flips depending on one variable most coverage glosses over: whether the money is already inside the 401(k) or still in a paycheck.
Here is the goal, stated plainly, because the goal drives everything else: a retiree with $1.6 million in a traditional 401(k) is holding an asset with a silent partner. The IRS owns a slice of it. Required minimum distributions (RMDs — mandatory annual withdrawals) begin at age 73 under current rules, and every dollar pulled out is taxed as ordinary income. Roth assets have no RMDs during the owner's lifetime and grow tax-free. The three moves are all attempts to buy the silent partner out. They just charge wildly different prices.
Side by Side: Why the Ranking Flips
The non-obvious point first: a Roth conversion and a mega backdoor Roth are often discussed in the same breath, as if they were two flavors of the same idea. They are close to opposites. One is a purchase of tax-free space using money you already have. The other is a transfer of tax-free space using money you have not yet earned.
Run the numbers. As of August 3, 2026, the IRS caps the employee deferral at $23,000 for 2025 ($30,500 for savers age 50 and up), while the total contribution limit across employee, employer, and after-tax dollars sits at $69,000 ($76,500 age 50+). The gap between those two figures is the mega backdoor lane. Subtract the deferral from the total and you get $46,000 of after-tax room for the age-50-plus saver — a figure the 24/7 Wall St. framing highlights as separate from the ordinary deferral. That $46,000 costs nothing in extra tax. It is contributed with money already taxed as wages, and once inside the Roth bucket it compounds untouched.
Now price a conversion of the same $46,000 out of the existing $1.6 million balance. A high earner sitting above the married-filing-jointly Roth phase-out — which began at $236,000 in 2025, with $150,000 for single filers, per limits that adjust for inflation — is by definition in an upper federal bracket. Converting $46,000 stacks on top of that income and is taxed immediately at ordinary rates. The saver ends up with meaningfully less than $46,000 working inside the Roth unless the tax is paid from a taxable brokerage account, which is its own opportunity cost.
Chart: IRS 2025 401(k) contribution limits. The $46,000 after-tax gap between the employee deferral and the total limit is the mega backdoor lane — and it is the only one of the three moves that adds tax-free dollars without triggering a tax bill.
So who wins under which condition? If the saver still has earned income and an employer plan that permits after-tax contributions plus in-service distributions or in-plan Roth transfers, the mega backdoor wins on price, full stop. If the plan does not support it — and many do not, which is the binding constraint the strategy pieces tend to bury — the mega backdoor is not a strategy, it is a wish. Then the conversion moves up the list by default. And the plain backdoor Roth, capped at ordinary IRA contribution levels, is the smallest of the three by a wide margin: useful, but on a $1.6 million balance it is a rounding error unless it is run every single year for decades.
The skeptic's pushback deserves an answer. Why convert at all if it costs current tax? Two reasons. Financial advisors commonly recommend conversions during lower-income years or market downturns, precisely because the tax bill scales with the converted value — a portfolio that has dropped converts more shares for the same tax. And SECURE Act 2.0, passed in December 2022, raised the RMD age to 73 in 2023 and schedules an increase to 75 in 2033. A longer runway before forced withdrawals means more years of untaxed compounding for whatever is moved into the Roth column — which is exactly why the deferral is not free, only postponed.
Photo by Abhinav Arya on Unsplash
The Habit That Actually Does the Work
Every one of these moves fails the same way: it becomes an annual project that gets skipped. The mega backdoor in particular is a payroll setting, not a decision. Set the after-tax contribution percentage once, turn on automatic in-plan Roth conversion if the plan offers it, and the $46,000 lane fills itself. Automate it once and forget it. A conversion, by contrast, genuinely requires a yearly look — at the bracket, at the market, at whether this is a low-income year.
One caution on legislative risk, since it comes up every cycle: the IRS has repeatedly confirmed backdoor Roth strategies as legal despite periodic proposals to end them, most recently during the Build Back Better negotiations in 2021 and 2022. That history argues for using the door while it is open rather than waiting for certainty that never arrives — the same wait-versus-act tension Smart Auto AI examined with solid-state EV batteries, where holding out for a better version costs real years.
The AI angle is thin here, and forcing it would be dishonest: the constraint is plan documents and tax brackets, not analytics. That said, the conversion-timing question — how much to convert in a given year without spilling into a higher bracket — is exactly the kind of narrow, rules-based optimization that tax software and the projection tools inside major brokerage platforms now handle competently. Use them for the arithmetic, not the decision.
Bottom Line
Our read: for a high earner still drawing a paycheck, the mega backdoor Roth is the highest-value of the three moves by a comfortable margin, and its only real gatekeeper is whether the employer's plan document allows it — which is a phone call, not an analysis. Conversions are the fallback and the retirement-transition tool, best deployed in a down market or a low-income year. On balance, the likeliest outcome for someone who does nothing is not a disaster; it is a perfectly fine retirement with a larger-than-necessary tax bill starting at 73. Rich is income. Wealthy is the number of years your money compounds without anyone taking a cut.
One call to the plan administrator this month answers the question that determines everything else. Make it.
Frequently Asked Questions
What is a backdoor Roth IRA and how does it work for high earners?
It is a two-step maneuver: contribute to a traditional IRA (which has no income limit on contributions), then convert that balance to a Roth IRA. Because Roth conversions carry no income ceiling, the income limit that blocks a direct Roth contribution never applies. The IRS has repeatedly confirmed the approach is legal, including through the Build Back Better negotiations of 2021 and 2022 when proposals to close it did not become law.
Can high earners contribute to a Roth IRA in 2026?
Not directly, above the phase-out. The 2025 phase-out started at $150,000 for single filers and $236,000 for married filing jointly, and these thresholds typically adjust for inflation each year. As of August 3, 2026, the practical answer for someone with a $1.6 million 401(k) is that direct contributions are off the table and the backdoor, mega backdoor, or conversion routes are the alternatives.
What is a mega backdoor Roth 401(k) and how much can it hold?
It uses the space between the employee deferral limit and the total 401(k) limit. For 2025 the IRS set the deferral at $23,000 ($30,500 age 50+) and the total employee-plus-employer-plus-after-tax limit at $69,000 ($76,500 age 50+), leaving up to $46,000 of after-tax room for the age-50-plus saver that can be moved into Roth treatment. One expert framing calls it among the most powerful wealth-building tools available to high earners — with the critical caveat that it requires employer plan support for after-tax contributions and in-service distributions.
Should I convert my 401(k) to a Roth IRA if I am in a high tax bracket?
Conversions have no income limit, but they trigger immediate tax on the converted amount at ordinary rates. Financial advisors generally suggest timing them for lower-income years or market downturns to reduce the bill. The offsetting benefit is that Roth assets face no required minimum distributions during the owner's lifetime, while traditional 401(k) balances trigger RMDs at 73 under SECURE Act 2.0, rising to 75 in 2033.
Disclaimer: This article is editorial commentary for informational purposes only and does not constitute financial, tax, or investment advice. It reflects analysis of publicly reported information and does not involve independent product testing. Consult a qualified tax professional before executing any Roth strategy. Research based on publicly available sources current as of August 3, 2026.