Roth IRA Conversions
What They Are, When They Work, and When to Think Twice
Few tax-planning moves generate as much client interest — or as much confusion — as the Roth IRA conversion. Done thoughtfully, it can be one of the most powerful tools in a high-net-worth client's tax strategy. Done carelessly, it can trigger an unnecessary tax bill with little long-term benefit.
This article walks through the mechanics, the advantages, the drawbacks, and the key scenarios that make a Roth conversion genuinely worthwhile.
The Basics: What Is a Roth Conversion?
A Roth IRA conversion is the process of moving money from a pre-tax retirement account — a traditional IRA, 401(k), SEP-IRA, or similar — into a Roth IRA. The amount converted is added to your ordinary taxable income in the year of conversion and taxed accordingly. In exchange, that money and all future growth lives in the Roth permanently: tax-free.
Key point: You're not avoiding taxes — you're pre-paying them. The bet you're making is that paying taxes now, at today's rates, is better than paying them later at higher rates. |
The Advantages
Tax-Free Growth and Withdrawals
Once funds are in a Roth IRA, all growth is permanently tax-free. Qualified withdrawals — generally after age 59½ with the account open for at least five years — are never taxed. This is especially powerful for accounts expected to grow significantly over time.
No Required Minimum Distributions (RMDs)
Traditional IRAs and pre-tax 401(k)s require you to take RMDs starting at age 73 (under current law), whether you need the income or not. Roth IRAs have no RMDs during the original owner's lifetime, giving you full control over the timing and amount of withdrawals.
Tax Diversification
Having both taxable, pre-tax, and Roth accounts gives you flexibility to manage your tax bracket in retirement. You can draw from pre-tax accounts in low-income years and from Roth accounts in higher-income years — smoothing your lifetime tax burden.
Estate Planning Benefits
Roth IRAs pass to heirs income-tax-free. While beneficiaries are subject to a 10-year distribution window under the SECURE Act, they inherit tax-free dollars rather than a future tax liability — a meaningful distinction for wealth transfer planning.
Hedge Against Future Tax Rate Increases
With the federal debt trajectory and the scheduled sunset of the Tax Cuts and Jobs Act provisions (now made permanent under P.L. 119-21), locking in today's known rates against future legislative uncertainty is a compelling argument for many clients.
The Disadvantages
You Pay Taxes Now — Potentially at a High Rate
Converting a large balance can push you into a higher marginal bracket, trigger the Net Investment Income Tax (3.8%), or cause Medicare IRMAA surcharges on your Part B and D premiums. Timing and size of the conversion matter enormously.
The Five-Year Rule Applies
Each Roth conversion has its own five-year clock for penalty-free withdrawal of the converted principal. If you're under 59½ and may need access to those funds, this is a meaningful constraint.
Opportunity Cost of the Tax Payment
If you fund the tax bill from the converted amount itself rather than from outside taxable assets, you reduce the tax-free compounding benefit significantly. The math works best when taxes are paid from a separate, non-retirement account.
May Not Make Sense If Future Tax Rates Are Lower
If you expect your income — and therefore your tax bracket — to be materially lower in retirement, a pre-tax account may ultimately serve you better. Conversions are most compelling when today's rate and tomorrow's rate are close, or when tomorrow's is likely higher.
When a Roth Conversion Makes Sense
Scenario | Why It May Warrant a Conversion |
Temporarily Low-Income Year | Job transition, sabbatical, early retirement, or business loss can create a window where lower marginal rates make conversion unusually attractive. |
Pre-RMD Window | Ages 59½ to 72 often represent a gap between earned income and mandatory distributions — a natural window for systematic conversions. |
Large Pre-Tax IRA Balance | Clients with $500K–$3M+ in IRAs face a looming RMD problem. Systematic conversions can reduce future forced distributions and smooth the tax profile over time. |
Estate Planning Goals | Clients who don't expect to need their IRA for living expenses and want to pass wealth tax-efficiently to heirs are strong candidates. |
Business Owner in a Down Year | A year with lower QBI or higher deductions may create room for a conversion without moving significantly up the bracket ladder. |
Recent Market Decline | Converting when account values are depressed means paying tax on a lower balance — and allowing the recovery to occur in the tax-free Roth environment. |
SECURE Act Beneficiaries | If heirs will be in a high tax bracket and face a 10-year distribution window, pre-converting reduces their inherited tax burden. |
When to Think Twice
You are currently in the 37% bracket and expect to be in 22–24% in retirement.You would need to tap the IRA itself to fund the tax bill, materially eroding the converted amount.You are over 70 and have not yet taken your RMD for the year — Roth conversions cannot satisfy an RMD.You have significant medical expenses, carry capital loss carryforwards, or have other deductions that reduce taxable income anyway.You are subject to IRMAA or are near the NIIT threshold and a conversion would trigger a disproportionate surcharge.
The Strategic Framework: Bracket Filling
The most disciplined approach to Roth conversions is not converting as much as possible in any one year — it's converting up to a specific bracket ceiling each year. For example, a married couple with $200,000 of ordinary income in the 24% bracket has approximately $131,450 of room before reaching the 32% bracket (based on 2025 thresholds). A systematic conversion that fills to — but does not cross — that threshold captures meaningful tax-free potential at a known, controlled rate.
At SC Advisors, we model multi-year Roth conversion strategies as part of integrated tax and investment planning — not as a one-time event, but as a disciplined annual process coordinated with your CPA. |
A Note on the One Big Beautiful Bill (P.L. 119-21)
The recently enacted legislation made permanent the individual income tax brackets introduced under the Tax Cuts and Jobs Act, including the top rate of 37%, the 22% and 24% brackets for middle-income earners, and the expanded standard deduction. This removes some of the urgency around the prior scheduled 2025 sunset — but it does not eliminate the case for conversions. RMD management, estate planning, and lifetime tax-bracket smoothing remain compelling independent of rate-change speculation.
The expanded SALT deduction (now $40,000 for joint filers through 2029) may also affect the calculus for clients in high-tax states, as it reduces the effective federal tax cost in those years.