A Roth conversion is worth it when your current tax rate is lower than your expected retirement tax rate. You pay taxes now at a known rate and get tax-free growth and withdrawals for life — plus no required minimum distributions.

Quick Decision Framework

Your Situation Roth Conversion? Why
Low-income year (between jobs, early retirement) ✅ Yes Fill up low tax brackets with conversions
Currently in 12% or 22% bracket, expect higher in retirement ✅ Yes Lock in low rate now
Large traditional IRA/401(k), worried about RMDs ✅ Yes Reduces future required distributions
Currently in 32%+ bracket ❌ Probably not High tax cost now
Retiring soon, income will drop permanently ❌ No You’ll be in a lower bracket anyway
Need the money within 5 years ❌ No 5-year rule penalizes early withdrawal
Have to pay taxes from the IRA itself ❌ No Defeats the purpose
Expect tax rates to increase in the future ✅ Yes Pay known rate now

How a Roth Conversion Works

Step What Happens
1 Move money from traditional IRA/401(k) to Roth IRA
2 Converted amount is added to your taxable income for the year
3 You pay income tax on the converted amount (no 10% penalty regardless of age)
4 Money grows tax-free in Roth IRA
5 Withdrawals are tax-free after age 59½ and 5-year rule is met
6 No required minimum distributions — ever

Tax Cost by Conversion Amount

Single filer, $50,000 regular income, converting additional amounts:

Conversion Amount Tax Bracket Used Federal Tax on Conversion Effective Rate
$0 22% (existing income) $0
$10,000 22% $2,200 22%
$25,000 22% $5,500 22%
$50,000 22% ($48K) + 24% ($2K) $11,040 22.1%
$100,000 22-32% $24,340 24.3%

Strategy: Convert just enough to fill your current bracket. Converting $48,000 stays in the 22% bracket. Converting $50,000+ pushes into 24%.

2026 Tax Bracket Opportunity

The 2017 Tax Cuts and Jobs Act (TCJA) provisions are set to expire after 2025. If Congress doesn’t extend them:

Bracket (2025) Bracket (2026 if TCJA expires) Change
10% 10% Same
12% 15% +3%
22% 25% +3%
24% 28% +4%
32% 33% +1%
35% 35% Same
37% 39.6% +2.6%

If rates increase, Roth conversions done at 2025 rates will look very smart in hindsight.

The RMD Problem

At age 73 (75 starting 2033), you must take required minimum distributions from traditional IRAs and 401(k)s:

Traditional IRA Balance at 73 First-Year RMD (~3.8%) Tax at 22% Tax at 24%
$500,000 $18,870 $4,151 $4,529
$1,000,000 $37,740 $8,303 $9,058
$2,000,000 $75,470 $16,603 $18,113
$3,000,000 $113,210 $24,906 $27,170

Large RMDs can push you into higher brackets and trigger Medicare IRMAA surcharges ($2,000+/year). Roth conversions before 73 reduce this.

Best Timing for Roth Conversions

Life Stage Tax Opportunity Conversion Strategy
Early career (20s-30s) Low income, low bracket Contribute directly to Roth; conversions less needed
Peak earning years (40s-50s) High bracket Usually not ideal — high tax cost
Early retirement (55-65) Gap between career income and Social Security/RMDs Prime conversion window — fill low brackets
Before Social Security (62-70) Income may be very low Excellent — convert at lowest rates
After 73 (RMDs begin) Must take RMDs + conversion amount increases income Still possible but more complex to manage brackets

Example: The Early Retirement Conversion Ladder

Retired at 55, living on savings, no earned income:

Year Conversion Amount Tax Bracket Federal Tax
Age 55 $50,000 12% $4,200
Age 56 $50,000 12% $4,200
Age 57 $50,000 12% $4,200
Ages 55-67 $600,000 total 12% $50,400 total

If that $600,000 stayed in traditional IRA and was withdrawn at 22-24% in retirement: $132,000-$144,000 in taxes. Conversion savings: ~$82,000-$94,000.

The 5-Year Rule

Each conversion has its own 5-year clock:

Rule Details
What it applies to Converted amounts (not earnings) withdrawn before age 59½
Penalty 10% on converted amount if withdrawn within 5 years AND before 59½
When it doesn’t matter If you’re already 59½+, no penalty regardless of 5-year rule
Strategy Convert early; let the 5-year clock run

The Bottom Line

Do a Roth conversion if you’re in a lower tax bracket now than you expect in the future — especially during early retirement, career gaps, or before RMDs kick in at 73. Convert just enough to fill your current bracket each year. Pay the taxes from a separate account, not the IRA itself.

The biggest opportunities: the years between retirement and Social Security, and the potential of higher tax rates after 2025 TCJA expiration.

Related: Should I Contribute to Roth or Traditional? | Roth IRA Contribution Limits