Roth Conversions for High-Income Earners in California: When Do They Make Sense?
If you earn a high income in California, you may be unable to contribute directly to a Roth IRA because of the income limitations. Roth conversions are different. There is no comparable income limit preventing a high-income taxpayer from converting eligible pre-tax retirement assets to a Roth IRA.
That does not necessarily mean you should.
For high earners in Newport Beach and throughout coastal Orange County, the decision can be particularly complicated because a conversion may create both federal and California income tax in the year it occurs. Converting during peak earning years can mean voluntarily recognizing income when your marginal tax rate is already high.
At other points in your financial life, however, a Roth conversion can be extremely useful. A temporary decline in income, the years immediately following retirement, estate planning considerations, or unusually large pre-tax retirement balances can all change the calculation. The real question is not simply whether you can do a Roth conversion. It is whether paying tax on that money today is likely to improve your long-term financial and tax position.
What Is a Roth Conversion?
A Roth conversion moves money from a traditional IRA or another eligible pre-tax retirement account into a Roth IRA. Generally, the portion of the conversion that has not already been taxed is included in taxable income in the year of the conversion.
In exchange for paying the tax today, the converted assets can continue growing inside the Roth IRA, and qualified Roth distributions can eventually be received free of federal income tax.
For a California resident, the taxable portion of a Roth conversion is generally included in California taxable income as well, although differences between federal and California IRA basis can occasionally affect the calculation.
This creates a tradeoff. You are giving up tax deferral today in exchange for potentially avoiding tax on those dollars, and their future growth, later. Whether that tradeoff is worthwhile depends heavily on the tax rate you pay when converting compared with the tax rate that would otherwise apply to future distributions.
Do Roth Conversions Make Sense for High-Income Earners?
Roth conversions can make sense for high-income earners, but they are often most attractive during years when taxable income is temporarily lower than normal. Converting during your highest-earning years can result in paying tax at a relatively expensive point in your financial life.
This is why I generally think about Roth conversions as a tax-rate management strategy, rather than simply a retirement-account strategy.
Suppose someone earns a high salary for most of their 50s but plans to retire at 62. Converting a large traditional IRA at 58 could stack additional taxable income on top of an already high salary.
The same person might have a very different opportunity at 63. Their salary has disappeared, Social Security may not have started yet, and required minimum distributions may still be years away. Suddenly, there may be considerably more room to recognize income at attractive marginal rates. The account did not change. The timing did.
How Does California Affect a Roth Conversion?
California generally taxes the taxable portion of a Roth conversion as income, which can make conversions more expensive for California residents than for taxpayers living in states without an individual income tax.
That additional layer matters when evaluating the conversion.
For someone already earning substantial income in California, adding a large Roth conversion can push additional dollars into relatively high marginal tax rates. A conversion that looks attractive when considering federal taxes alone may look considerably less compelling after California taxes are incorporated.
There can also be differences between a taxpayer's federal and California IRA basis, particularly in certain historical situations, so the California taxable amount does not necessarily match the federal amount in every case. This is one reason Roth conversion planning should be coordinated with the actual tax return rather than evaluated solely through an investment account.
When Can a Roth Conversion Make Sense for High Earners in California?
A Year When Your Income Is Temporarily Lower
A temporary decline in income can create one of the best opportunities for a Roth conversion because the converted amount may be taxed at a lower marginal rate than it would be during your normal earning years.
This can happen for many reasons. You might leave a corporate position to start a business, take a sabbatical, retire partway through the year, or experience an unusually large deduction.
These years are worth identifying in advance because the opportunity may be temporary.
For example, a business owner who normally earns substantial income might sell or wind down a company and have one relatively quiet tax year before investment income, retirement distributions, or another business venture increases taxable income again. Rather than viewing that year as an anomaly, it may be useful to treat it as a planning window.
The Years After Retirement but Before Required Minimum Distributions
The period after retirement and before required minimum distributions begin can create an especially valuable Roth conversion window.
During your working years, wages or business income may fill much of the lower portion of your tax brackets. Once you retire, that income may disappear.
Later, required distributions from large pre-tax retirement accounts can push taxable income higher again.
The years between those two periods can provide room to intentionally recognize income through partial Roth conversions. Rather than converting an entire IRA at once, the strategy may involve converting a calculated amount each year based on the taxpayer's projected income, deductions, investment income, Medicare considerations, and desired marginal tax rate.
Estate Planning for Large Traditional IRA Balances
Roth conversions can also become more attractive when a taxpayer expects to leave substantial retirement assets to children or other non-spouse beneficiaries.
Under current inherited IRA rules, many non-spouse beneficiaries must fully distribute inherited retirement accounts within a specified period following the original owner's death. Traditional IRA distributions are generally taxable to the beneficiary, which can create an unfortunate result when adult children inherit large accounts during their own peak earning years.
A Roth IRA does not eliminate the inherited-account distribution rules, but qualified Roth distributions are generally income-tax-free.
That means the relevant comparison may extend beyond your own retirement tax bracket. In some families, it is worth comparing the tax you would pay on a conversion today with the potential tax burden your beneficiaries could face on inherited traditional retirement assets later. Estate planning should not drive every Roth conversion decision, but for families with significant pre-tax retirement assets, it belongs in the analysis.
Reducing Future Required Minimum Distributions
Converting part of a traditional IRA to a Roth IRA reduces the amount remaining in the traditional IRA that will eventually be subject to required minimum distributions.
This can be valuable when someone has accumulated substantial pre-tax retirement assets and expects those balances to continue growing before distributions begin.
Future RMDs can affect more than the income tax bill. Higher taxable income can interact with Medicare premiums and other parts of the financial plan. A series of deliberate conversions over several lower-income years can sometimes create a smoother tax profile than simply allowing a large traditional IRA to grow until required distributions begin.
Creating Tax Diversification in Retirement
Holding money across taxable, tax-deferred, and Roth accounts can give retirees more control over where their spending comes from and how much taxable income they recognize in a particular year.
A retiree who holds nearly everything in a traditional IRA has relatively little flexibility. Most withdrawals generate taxable income.
Someone with meaningful Roth assets may have more choices. That flexibility can become valuable in years with unusually high spending, significant capital gains, changes in tax law, or other events that make controlling taxable income particularly important.
When Might a Roth Conversion Not Make Sense?
You Are Currently in Your Peak Earning Years
A Roth conversion may be less attractive when you are already paying some of the highest marginal tax rates you expect to face during your lifetime.
The conversion adds taxable income today. If you reasonably expect to withdraw the same money later at a materially lower tax rate, accelerating the tax can work against you.
This is especially relevant for high-income California residents who expect to retire in a lower tax bracket or eventually establish residency in a state with lower or no individual income tax. In that situation, waiting may have substantial value.
You Expect Your Future Tax Rate to Be Meaningfully Lower
If your expected tax rate on future traditional IRA distributions is substantially lower than the rate you would pay on a conversion today, continuing to defer the tax may be preferable.
The analysis should consider more than today's bracket versus an assumed retirement bracket. It should also consider where you expect to live, future required distributions, Social Security, investment income, estate plans, and the composition of your other assets. The farther retirement is in the future, the more uncertain those assumptions become.
Paying the Conversion Tax Would Create a Liquidity Problem
Roth conversions are generally more attractive when the resulting tax can be paid from assets outside the retirement account.
Using part of the retirement distribution itself to cover the tax leaves less money invested inside the Roth and can reduce the strategy's long-term benefit. Depending on your age and circumstances, distributions used to pay taxes may also create additional considerations. That does not automatically make a conversion inappropriate, but the source of the tax payment should be part of the analysis before executing one.
Should You Convert Your Entire Traditional IRA at Once?
For many high-income taxpayers, converting an entire large traditional IRA in one year is less attractive than spreading conversions across multiple years.
A large one-time conversion can stack substantial additional income into higher marginal tax brackets. Partial conversions allow you to manage the amount of income recognized each year.
For example, instead of asking, "Should I convert my $1 million IRA?" a more useful planning question might be:
How much should I convert this year given the rest of my income and long-term tax projections?
That framing turns the Roth conversion from an all-or-nothing decision into an annual tax-planning decision. In some years, the answer may be zero. In another year, a significant conversion may make sense.
How Can a Roth Conversion Affect Medicare IRMAA?
A Roth conversion can increase Medicare Part B and Part D premiums because the taxable conversion increases income used in determining Medicare's Income-Related Monthly Adjustment Amount, or IRMAA.
Medicare generally bases IRMAA on tax information from two years earlier. As a result, a large conversion in one year can affect Medicare premiums in a later year if the additional income moves the taxpayer into a higher IRMAA tier.
That does not necessarily mean you should avoid the conversion. Paying temporarily higher Medicare premiums can still be worthwhile if the conversion creates a larger long-term tax benefit. It simply means the IRMAA cost should be included in the calculation rather than discovered after the conversion has already occurred.
What Is the Backdoor Roth IRA, and Is It the Same as a Roth Conversion?
A backdoor Roth IRA uses a Roth conversion, but it is generally a contribution strategy rather than a strategy for converting a large existing retirement account.
High-income taxpayers may be unable to contribute directly to a Roth IRA because of income limitations. A backdoor Roth typically involves making a nondeductible contribution to a traditional IRA and subsequently converting that amount to a Roth IRA.
When someone has little or no other pre-tax IRA money and the conversion occurs before significant earnings accumulate, the taxable amount may be relatively small.
The calculation becomes more complicated when the taxpayer already holds pre-tax assets in traditional, SEP, or SIMPLE IRAs.
Under the pro-rata rules, you generally cannot isolate only the nondeductible dollars and treat those as the dollars being converted. The tax calculation considers the taxpayer's applicable IRA balances together, which can cause part of the conversion to be taxable.
This is one of the most common issues to review before implementing a backdoor Roth strategy. For related context on retirement account strategy and how contribution timing interacts with your tax picture, see Maximize Your Retirement Contributions to Lower Taxes.
What Should You Analyze Before Doing a Roth Conversion?
A Roth conversion analysis should compare the tax cost of converting today with the expected tax consequences of leaving the assets in the traditional retirement account.
For high-income California taxpayers, I would generally want to understand:
Current and projected taxable income
Expected retirement date and future income sources
Traditional IRA and employer retirement-plan balances
Expected required minimum distributions
Taxable assets available to pay the conversion tax
Expected state of residence in retirement
Medicare and IRMAA implications
Estate plans and likely beneficiaries
Existing Roth assets and overall tax diversification
None of those variables should be considered in isolation.
A client who looks like a poor Roth conversion candidate based solely on current income may become an excellent candidate three years later after retiring. Someone who expects to leave California may want to preserve pre-tax assets until after establishing residency elsewhere. Another client with a very large traditional IRA and high-income adult children may place greater value on reducing future taxable inherited retirement assets.
This is where coordinating the tax return with the investment and financial plan becomes particularly useful. The objective is not to maximize the Roth balance. It is to determine which combination of accounts and tax treatments is most likely to produce the best long-term outcome.
Frequently Asked Questions About Roth Conversions for High-Income Earners
Can high-income earners do a Roth conversion?
Yes. Income limitations that can prevent high earners from contributing directly to a Roth IRA generally do not prevent them from converting eligible traditional IRA assets to a Roth IRA.
The taxable portion of the conversion is included in income in the year of conversion, so being allowed to convert does not necessarily mean converting during a high-income year is advantageous.
Are Roth conversions taxable in California?
Generally, yes. California generally includes the taxable portion of a Roth conversion in taxable income, although differences between federal and California IRA basis can cause the California taxable amount to differ in certain situations.
For high-income California residents, state income tax can materially increase the immediate cost of a Roth conversion and should be incorporated into the analysis.
When is the best time to do a Roth conversion?
The most attractive time for a Roth conversion is often a year when your marginal tax rate is temporarily lower than the rate you expect to face on those assets in the future.
For many people, this occurs after retirement but before required minimum distributions begin. Other opportunities can arise during sabbaticals, career transitions, business startup years, or other temporary declines in taxable income.
Is there an income limit for Roth conversions?
No. The income limitations applicable to direct Roth IRA contributions do not impose the same restriction on Roth conversions.
High-income taxpayers can therefore still consider Roth conversions even when their income prevents them from making direct Roth IRA contributions.
What is the pro-rata rule for a backdoor Roth IRA?
The pro-rata rule generally prevents a taxpayer with both pre-tax and after-tax IRA money from treating a conversion as coming exclusively from the after-tax dollars.
Traditional, SEP, and SIMPLE IRA balances can affect the calculation. As a result, someone with a large pre-tax IRA may create taxable income when implementing a backdoor Roth even though the recent traditional IRA contribution itself was nondeductible.
Does a Roth conversion affect Medicare premiums?
It can. The taxable portion of a Roth conversion increases income and can cause a Medicare beneficiary to pay higher income-related Part B and Part D premiums if it moves income above an applicable IRMAA threshold.
Because Medicare generally uses tax information from two years earlier, the premium impact may occur after the year of the conversion.
Should I convert my entire traditional IRA at once?
Usually, a large Roth conversion should be compared with a multi-year partial-conversion strategy before proceeding.
Spreading conversions across several years may allow a taxpayer to manage marginal tax brackets and other income-related costs more effectively. There are situations where a larger conversion is appropriate, but the amount should generally be modeled rather than selected arbitrarily.
Does a Roth conversion always save taxes?
No. A Roth conversion accelerates income tax, and whether it ultimately saves money depends on the tax rate paid today compared with the tax consequences of leaving the money in the traditional account.
Future tax rates, investment growth, state residency, required distributions, Medicare premiums, estate planning, and how the conversion tax is funded can all affect the outcome.
Summary
High-income taxpayers can generally complete Roth conversions even when their income prevents them from contributing directly to a Roth IRA.
A Roth conversion accelerates income tax today in exchange for future Roth treatment, so the tax rate at the time of conversion is a central part of the decision.
California generally taxes the taxable portion of Roth conversions, which can make conversions during peak earning years particularly expensive for high-income California residents.
Temporary lower-income years, especially the period after retirement and before required minimum distributions, can create attractive Roth conversion opportunities.
Partial conversions over several years may provide better control over marginal tax rates than converting a large traditional IRA all at once.
Roth conversions can affect Medicare IRMAA and should also be evaluated alongside estate planning, future RMDs, state residency, and the taxpayer's broader investment portfolio.
A backdoor Roth IRA uses a conversion but involves additional considerations, including the pro-rata rule when traditional, SEP, or SIMPLE IRA balances exist.
A Roth conversion is ultimately a tax-planning decision as much as an investment decision. If you are considering a Roth conversion and want help evaluating how it fits with your taxes, retirement accounts, and broader financial plan, visit KCL Wealth Management to request an intro call.
Author Bio
Katherine Leonard, CPA, CFP®, is the founder of KCL Wealth Management, a fee-only wealth management firm serving clients in Newport Beach, Orange County, and throughout California. She specializes in tax-efficient financial planning and investment management, helping clients coordinate their investment strategy, tax planning, and broader financial decisions.