Moving pre-tax money into a Roth — from Traditional IRAs, 401(k)s, and other qualified plans — means triggering income tax now to create tax-free growth later. The rules, timing, and tax math vary meaningfully by source account.
Roth Conversion Rules
The core mechanics, IRS guidance, and why TCJA ended recharacterization.
5-Year Rule for Conversions
Each conversion starts its own 5-year clock — how to track them across years.
Conversion Tax Implications
How conversions are taxed, bracket-fill strategy, and timing windows.
Backdoor Roth IRA
High-earner pathway around the MAGI phase-out.
Pro-Rata Rule
IRA aggregation under IRC §408(d)(2) and the tax on backdoor conversions.
Mega Backdoor Roth
Up to $47,500 more Roth dollars via after-tax 401(k) contributions ($72,000 §415(c) limit − $24,500 elective deferral = $47,500, 2026 figures).
529 to Roth Conversion
SECURE 2.0 §126, the 15-year window, and lifetime $35,000 cap.
Rollover Rules
Direct vs. indirect rollovers, limits, and the one-year rule.
401(k) to Roth IRA
Rollover steps, tax implications, and sequencing with existing IRAs.
Roth 401(k) Rules
Contribution limits, withdrawals, and the post-SECURE-2.0 RMD change.
60-Day Rollover Rule
Deadline mechanics, the one-per-year limit, and the waiver procedure.
Conversion Planner Tool
Multi-year, bracket-filling, IRMAA-aware schedule builder.
True Cost of a Conversion
Fed + state + IRMAA + SS torpedo + NIIT + LTCG in one snapshot.
Frequently Asked Questions
What is a Roth conversion?
A Roth conversion is the transfer of pre-tax retirement dollars (from a Traditional IRA, 401(k), 403(b), SEP-IRA, or SIMPLE IRA after the two-year holding period) into a Roth IRA. The entire converted amount is added to your taxable income in the conversion year; growth and qualified distributions from the Roth are then tax-free.
Is there an income limit for Roth conversions?
No. Congress removed the income cap on Roth conversions effective 2010. Any taxpayer, at any income level, can convert any amount from a pre-tax retirement account to a Roth. The income cap still applies to direct Roth contributions — which is the gap the Backdoor Roth technique fills.
Do I pay tax on a Roth conversion?
Yes, on the pre-tax portion. Any converted amount that represents deductible contributions or pre-tax employer dollars (plus all earnings) is ordinary income in the conversion year. After-tax basis — documented on Form 8606 — converts tax-free. The pro-rata rule (IRC §408(d)(2)) governs how basis is allocated when you hold both pre-tax and after-tax IRA dollars.
How much should I convert in a given year?
The disciplined answer is: convert up to the top of whichever tax bracket you want to fill without spilling into a higher one, and watch IRMAA cliffs two years forward if you are near Medicare age. A multi-year ladder is almost always more efficient than a single large conversion.
What is the five-year rule on conversions?
Each conversion starts its own five-year clock, beginning January 1 of the conversion year. If you withdraw converted principal before age 59½ and before the clock matures, you owe the 10% penalty on the pre-tax portion (earnings follow a separate rule). At or after 59½, converted principal may be taken without penalty regardless of the clock.