Roth Conversions vs. Roth Contributions: Which One Should You Prioritize?

If you earn too much to contribute directly to a Roth IRA, you still have two paths into one: the backdoor Roth contribution and the Roth conversion. They are not the same thing, and treating them as interchangeable is a mistake that costs high earners real money.

What Each One Actually Is

A Roth contribution is money you put in directly, up to the annual IRS limit ($7,000 in 2024, $8,000 if you're 50 or older). It comes from after-tax dollars. Once it's in, it grows tax-free and never triggers a required minimum distribution. Simple.

The income phase-out for direct contributions begins at $146,000 modified adjusted gross income (MAGI) for single filers and $230,000 for married couples filing jointly in 2024. If you're a HENRY (high earner, not rich yet), you've probably already crossed those thresholds. Direct contributions are off the table unless you use the backdoor method.

A Roth conversion is a different animal. You take money that already sits in a traditional IRA, 401(k), or similar pre-tax account and move it into a Roth. There is no income limit. There is also no dollar cap. But every dollar you convert adds to your taxable income in the year of the conversion, at ordinary income rates. You are paying the tax bill today in exchange for tax-free growth later.

The Rules, Tradeoffs, and Watchouts

Start with the backdoor Roth contribution, because the mechanics matter. You contribute to a traditional IRA (non-deductible, since you're likely covered by a workplace plan and over the income limit for a deduction), then convert that IRA to Roth shortly after. The contribution is after-tax, so the conversion generates little or no additional tax, assuming no other pre-tax IRA balances exist.

That last clause is the trap. The IRS applies the pro-rata rule when you convert. If you have $95,000 sitting in a rollover IRA from an old 401(k) and you add $7,000 in a non-deductible contribution, only about 6.8% of any amount you convert is considered after-tax. The rest is taxable. The backdoor only works cleanly when your pre-tax IRA balance is zero or negligible.

Conversions, on the other hand, have their own set of watchouts. Converting a large sum in a single year can push you into a higher marginal bracket. It can also trigger IRMAA surcharges on Medicare Part B and D premiums two years later (relevant if you're converting in your early 60s) and affect ACA premium subsidies if you're not yet on Medicare. These are not edge cases. They are common outcomes for people who convert without modeling the full picture first. The parent pillar, Roth Conversion: A Practical Guide for High Earners and Pre-Retirees, covers the IRMAA and ACA interactions in detail.

The five-year rule applies to both paths. Each conversion starts its own five-year clock for penalty-free withdrawal of converted principal if you're under 59½. Contributions have a separate clock. Keep the two buckets straight.

When to Prioritize Contributions vs. Conversions: A Worked Example

Consider a 38-year-old software engineer, married filing jointly, with $340,000 in household MAGI. She maxes out her 401(k) at work and has a rollover IRA with $180,000 from a previous employer, plus $7,000 she contributed non-deductibly this year.

Backdoor Roth option: She could convert the $7,000 non-deductible contribution. But the pro-rata rule applies. Her total IRA balance after the contribution is $187,000, of which $7,000 (3.7%) is after-tax. Converting only the $7,000 still leaves her with a taxable portion of roughly $6,740. She owes tax on almost the entire conversion. The backdoor doesn't work cleanly here.

Conversion option: She could convert, say, $40,000 from the rollover IRA. At her marginal rate (likely 22% to 24%), that costs her roughly $8,800 to $9,600 in federal tax now. If her effective rate in retirement is expected to be 22% or higher, the conversion breaks roughly even on a tax-rate basis, before accounting for the compounding of tax-free growth over 25-plus years.

The better move in her situation is to first roll the $180,000 IRA into her current employer's 401(k) if the plan accepts incoming rollers. That eliminates the pro-rata problem. Then she can do a clean backdoor contribution each year for $7,000. Separately, she can layer in modest annual conversions from the 401(k) after she leaves that employer, sized to stay within her current bracket.

The decision tree collapses to this: if you can contribute directly, do it first (it's the cheapest Roth dollar you'll ever get). If you can't, check whether a clean backdoor is possible given your IRA balances. If the pro-rata rule would taint the backdoor, convert strategically from pre-tax accounts instead, in amounts your current bracket can absorb without pushing you into the next one.

How This Connects to the Roth Conversion Pillar

Both contributions and conversions serve the same structural goal: moving assets into a tax-free bucket before retirement, when your income and tax rate are presumably lower than they will be during peak earning years. This work lives in the Soil layer of the Sporos Doctrine, the tax architecture phase where account-type decisions compound quietly over decades.

The broader context, including how to sequence conversions across multiple years, how to model bracket thresholds, and when conversions are clearly the wrong call, is covered in the Roth Conversion pillar at /strategies/roth-conversion.

Frequently Asked Questions

Can I do both a backdoor Roth contribution and a Roth conversion in the same year?

Yes. They are separate transactions. There is no rule preventing you from making a non-deductible IRA contribution and also converting additional pre-tax IRA funds in the same tax year. Just track the basis carefully using IRS Form 8606.

Does the backdoor Roth contribution count against the annual contribution limit?

It does. The $7,000 annual limit applies to the underlying contribution to the traditional IRA. The subsequent conversion to Roth does not count separately toward any limit.

What if my employer 401(k) doesn't accept incoming rollovers?

Then you're stuck with the pro-rata problem unless you can find a plan that does accept them. Some solo 401(k) plans also work if you have any self-employment income. This is worth investigating before doing a backdoor contribution with a large pre-tax IRA in the background.

Is there an income limit on Roth conversions?

No. Congress removed the income limit on conversions in 2010. Any amount, from any traditional IRA or eligible employer plan, can be converted regardless of your income.

How do I know if a conversion is worth it at my current tax rate?

The core question is whether your tax rate today is lower than your expected rate on withdrawals in retirement. If your rate is likely to be the same or lower in retirement, the conversion math often doesn't favor paying the tax now. A qualified advisor can model the break-even across different rate scenarios.

What is the risk of doing large conversions early?

Beyond the bracket and IRMAA risks already noted, large conversions reduce the liquidity you have available to pay the tax bill without liquidating other investments. It's generally better to pay conversion taxes from non-IRA funds so the entire converted amount stays invested.

What to Do Next

1. Check your current IRA balances and identify whether the pro-rata rule would affect a backdoor contribution this year.
2. Ask your 401(k) plan administrator whether the plan accepts incoming IRA rollovers. If yes, rolling a pre-tax IRA in may clean up your backdoor strategy.
3. Review your projected MAGI for the year before executing any conversion. Bracket proximity matters more than people realize.
4. Read the full Roth Conversion guide at /strategies/roth-conversion to understand how annual conversions fit into a multi-year drawdown plan.

The information provided is for educational purposes only and does not constitute investment, legal, or tax advice. Tax law changes frequently — verify current rules before acting. Consult with qualified professionals for guidance specific to your situation.