Is it worth doing Roth conversions in retirement?

For most retirees with significant traditional IRA or 401(k) balances, Roth conversions during the 'tax window' years (ages 60-72) are extremely valuable. The tax window is the period between retirement and when Social Security and RMDs kick in — years when your income is temporarily lower. Converting $50,000-$100,000/year during these low-income years at the 12% or 22% rate prevents those funds from being forced out as RMDs at potentially higher rates (24% or 32%) later. The math typically favors conversion when your current bracket equals or is lower than your expected future bracket.

What is the Roth conversion ladder?

A Roth conversion ladder is a strategy of converting a fixed annual amount from traditional IRA to Roth IRA over multiple years, typically to stay within a target tax bracket. For early retirees, it also serves a second purpose: Roth conversions become accessible penalty-free after 5 years, creating a 'ladder' of tax-free funds accessible before age 59½. For traditional retirees (ages 60-72), the ladder is primarily a tax strategy — converting each year to fill up the desired bracket before RMDs and Social Security raise income in future years.

How much should I convert in a Roth conversion?

The standard approach is to fill up your target tax bracket each year. Calculate: (bracket ceiling) minus (current taxable income from other sources) minus (standard deduction) = available conversion space. For example, a married 67-year-old with $32,000 Social Security (85% taxable = $27,200) and $12,000 in investment income, taking the $29,200 standard deduction, has taxable income of $10,000. The top of the 22% bracket (MFJ) is $206,700. Available 22% bracket space = $206,700 − $10,000 = $196,700. Converting $100,000-$150,000/year is feasible without entering the 24% bracket — though IRMAA thresholds ($212,000 for MFJ) act as a ceiling for those on Medicare.

Roth Conversion in Retirement: When to Convert and How Much

The window between retirement and age 73 (when RMDs begin) is often the best opportunity in your financial life to do Roth conversions. Income is typically lower than your working years, and lower than your RMD-heavy later years. Converting traditional IRA funds to Roth at today’s lower rate can save tens of thousands of dollars in lifetime taxes.

The Roth Conversion Tax Window

Phase	Typical Income	Roth Conversion Opportunity
Working years	High (wages)	Poor — high bracket, limited opportunity
Early retirement (60-64)	Low if not working	Excellent — low taxable income, large bracket space
Pre-RMD retirement (65-72)	Moderate (SS + portfolio)	Excellent — still relatively low; fill brackets before RMDs
RMD years (73+)	Higher due to RMDs	Less efficient — SS + RMDs fill brackets; conversions costly
Late retirement (80+)	SS + RMDs + maybe limited portfolio	Usually not worth converting; income already forced high

The sweet spot: Ages 60-72 are typically the lowest-income years in a retiree’s life. Use them.

Who Benefits Most From Roth Conversions

Profile	Why Conversions Are Valuable
Large traditional IRA ($500K+)	Future RMDs will force significant income; converting reduces that burden
No pension; low SS	Very low income pre-RMD; huge bracket space available
Healthy with long life expectancy	More years to benefit from tax-free Roth growth
Heirs who will inherit in high bracket	Converted Roth assets pass tax-free; inherited traditional IRA taxes heirs in 10-year window
IRMAA concern on Medicare	Reducing IRA balance reduces future RMD-driven MAGI

How Much to Convert: Bracket-Filling Method

Step 1: Identify your current taxable income (SS income × 85%, investment income, part-time work, etc.)
Step 2: Subtract standard deduction
Step 3: Find the ceiling of your target tax bracket
Step 4: Conversion available space = bracket ceiling minus step 2 result

2026 Example: Married Filing Jointly

Income Source	Amount
Social Security	$38,000/year
Social Security taxable (85%)	$32,300
Dividends/capital gains	$8,000
Standard deduction	$29,200
Taxable income before conversion	$11,100

Target Bracket	Ceiling	Available Conversion Space
Fill to top of 12%	$96,950	~$85,850
Fill to top of 22%	$206,700	~$195,600
IRMAA cliff (soft ceiling)	~$212,000	~$200,900

This retiree could convert $85,000-$195,000/year staying in 12-22% bracket — potentially eliminating most RMD risk with 3-5 years of conversions.

IRMAA: The Hidden Ceiling on Roth Conversions

For retirees on Medicare, the IRMAA (Income-Related Monthly Adjustment Amount) applies when Modified Adjusted Gross Income (MAGI) exceeds thresholds. Roth conversion income adds to MAGI:

MAGI (MFJ) 2026	Part B Premium Per Person	Annual Extra Cost Per Person
Up to $212,000	$185/month	$0
$212,001-$266,000	$259/month	$888/year
$266,001-$334,000	$369/month	$2,208/year
$334,001-$400,000	$479/month	$3,528/year
Over $400,000	$590/month	$4,860/year

Critical: IRMAA is assessed on your income from 2 years prior. A large Roth conversion in 2026 affects Medicare premiums in 2028.

Strategy: Stay just below $212,000 (MFJ) or $106,000 (single) in total MAGI to avoid IRMAA entirely. Above that threshold, compare the IRMAA cost to the future tax savings from converting.

ACA Subsidy Cliff (Pre-Medicare Retirees Ages 60-64)

If you haven’t started Medicare yet, be aware of the ACA (Affordable Care Act) health insurance subsidy:

Household Income	ACA Impact
Up to 400% FPL (~$72,000 for 2-person household)	Premium tax credits available
Over 400% FPL	Enhanced credits phase out
Very high income (post-ARPA rules)	No cliff; premium capped at 8.5% of income

Roth conversion inflates MAGI, which can dramatically increase your ACA insurance costs if you are not yet on Medicare and receiving premium tax credits.

Strategy for ages 60-64: Balance Roth conversion amount against ACA premium impact. Sometimes it’s better to delay conversions until Medicare eligibility at 65 if conversion creates a large ACA penalty.

Roth Conversion vs. Paying Taxes Later: The Math

Should you pay taxes now (conversion) or later (RMD)?

Scenario	Pay Now (Convert 22%)	Pay Later (RMD 24%)
Convert $100,000 today at 22%	Pay $22,000 in taxes	$0 today
Roth grows 7%/year for 10 years	$100,000 → $196,715 (tax-free)	Traditional IRA: $196,715
RMD at 83 (factor ~17.7)	$0	Pay $11,111 + in RMD taxes/year (~24% = $2,667)
10-year RMD tax cost	$0	~$26,670
Net savings from converting	~$4,670+ (plus bracket certainty)	None

This simplified example shows modest advantage. The advantage grows dramatically when:

The future tax rate is higher than conversion rate
The account grows significantly
RMDs push into IRMAA territory
Estate planning benefits of Roth to heirs are considered

Roth Conversion and Beneficiaries

Account Type	Beneficiary Tax Treatment
Inherited Traditional IRA	Taxed as ordinary income within 10-year distribution window
Inherited Roth IRA	Distributions are tax-free within 10-year window

If your heirs are in a 22-37% bracket, converting your traditional IRA to Roth at 12-22% is straightforwardly beneficial from an estate perspective.

Sequential Roth Conversion Strategy: Ages 62-72

Age	Approach	Range to Convert
62-64	Pre-Medicare: balance vs. ACA subsidy	$20,000-$60,000/year
65-69	On Medicare: fill bracket to IRMAA floor	$60,000-$120,000/year
70-72	SS delayed (70); last window before full RMDs	$50,000-$100,000/year
73+	RMDs force income; conversions less efficient	Convert only if clearly beneficial

Common Roth Conversion Mistakes

Mistake	Why It’s Costly
Converting too much in one year (bracket overshoot)	Pushes significant income into 24%+ bracket unnecessarily
Ignoring IRMAA thresholds	Converting $5,000 too much can trigger $1,776/year in Medicare surcharges per person
Forgetting state income taxes	State tax on conversions may make them less attractive in high-tax states
Paying conversion taxes from the IRA itself	Reduces conversions efficiency — pay taxes from after-tax accounts only
Not converting at all in the tax window	Misses the life’s-best opportunity to shift tax brackets
Converting only in the year RMDs begin	Should start 8-10 years earlier for maximum benefit