Why Withdrawal Order Matters
Most retirees accumulate savings across three tax buckets: taxable brokerage accounts, tax-deferred accounts (traditional IRA, 401(k)), and tax-free Roth accounts. Each bucket is taxed differently when you withdraw, and the sequence you choose directly affects your marginal tax rate each year, your Medicare premiums (IRMAA), and how much of your Social Security benefit is taxable.
A naive approach — withdrawing from whichever account is largest or most convenient — often pushes retirees into higher brackets in some years while leaving low brackets unused in others. Strategic sequencing smooths taxable income across decades, keeping you in lower brackets longer.
The Conventional Wisdom: Taxable First
The traditional withdrawal ordering rule is straightforward: spend from taxable accounts first, then tax-deferred accounts, then Roth accounts last. The logic is sound: taxable account withdrawals are taxed at favorable long-term capital gains rates, tax-deferred withdrawals generate ordinary income, and Roth withdrawals are completely tax-free, so you let the Roth compound the longest.
This approach works reasonably well for many retirees, but it is not optimal for everyone. The problem is that it ignores the opportunity to fill low tax brackets in the early years of retirement before Required Minimum Distributions (RMDs) force large taxable withdrawals.
Required Minimum Distributions (RMDs)
Starting at age 73 (under SECURE 2.0, rising to 75 in 2033), the IRS requires you to withdraw minimum amounts from traditional IRAs and most employer plans each year. RMDs are calculated by dividing your account balance by a life expectancy factor. As you age and your balance grows, RMDs can become substantial — often pushing retirees into the 22% or 24% bracket even if they need less income.
Failing to take RMDs triggers a 25% excise tax on the amount not withdrawn (reduced from the prior 50% penalty). This makes RMD planning essential, not optional.
The Roth Conversion Ladder in Retirement
The gap between retirement and RMD age is a golden window for tax optimization. If you retire at 62 and your RMDs begin at 73, you have 11 years where your taxable income may be unusually low — especially before Social Security kicks in. During this window, you can convert portions of your traditional IRA to a Roth IRA, paying tax at today's lower rates to avoid higher rates later.
The key is to convert just enough each year to fill up the 12% or 22% bracket without spilling into higher ones. For a married couple filing jointly in 2025, that means converting up to the top of the 22% bracket at $190,750 of taxable income — after accounting for other income sources like Social Security or part-time work.
Five-Year Rule for Conversions
Converted amounts must season for five years before they can be withdrawn penalty-free if you are under 59 and a half. For most retirees over 59 and a half, this is not a concern — the five-year rule still applies to conversions, but the 10% early withdrawal penalty does not apply after 59 and a half. You will owe ordinary income tax on the conversion in the year it occurs regardless of age.
Tax Bracket Management
The core principle of tax-efficient withdrawals is bracket management: filling each bracket fully before moving to the next, and never leaving low brackets unused. Here is a practical framework:
- Standard deduction first: In 2025, a married couple over 65 gets a standard deduction of roughly $32,300. This is free income — withdraw at least this much from tax-deferred accounts each year to use it.
- Fill the 10% and 12% brackets: After the deduction, the first $23,200 (single) or $46,400 (married) is taxed at just 10-12%. If your living expenses are covered by Social Security or taxable accounts, convert traditional IRA dollars to Roth to fill these brackets.
- Watch the 22% cliff: The jump from 12% to 22% is steep. Many retirees find it optimal to fill through the 22% bracket with Roth conversions but stop before hitting 24%.
- Coordinate with Social Security: Up to 85% of Social Security benefits become taxable when combined income exceeds $44,000 (married). Factor this into your bracket calculations.
IRMAA and Medicare Premium Surcharges
Income-Related Monthly Adjustment Amounts (IRMAA) add surcharges to Medicare Part B and Part D premiums when your modified adjusted gross income exceeds certain thresholds. In 2025, individuals with MAGI above $103,000 (or $206,000 for couples) pay higher premiums. The surcharges are based on income from two years prior, so a large Roth conversion in 2025 affects your Medicare premiums in 2027.
IRMAA creates a hidden marginal tax rate that can exceed the nominal bracket rate. A single dollar over a threshold can trigger several thousand dollars in annual premium increases. Smart withdrawal planning keeps MAGI just below these cliffs when possible.
Putting It All Together
An optimized withdrawal strategy is not a rigid formula — it adapts year by year based on your income, tax law, and account balances. But the general principles are consistent:
- Use the early retirement years (before RMDs) to do Roth conversions at low tax rates, reducing future RMD pressure.
- Spend from taxable accounts for living expenses while converting tax-deferred dollars to Roth in the same year.
- Once RMDs begin, take the required amount and supplement with Roth withdrawals to avoid bracket creep.
- Monitor IRMAA thresholds and capital gains brackets — they create hidden cliffs that are easy to trip over.
- Revisit the plan annually. Tax law changes, account balances shift, and personal circumstances evolve.
The difference between a naive withdrawal strategy and an optimized one can easily exceed $100,000 in lifetime tax savings for a couple with $1.5 million in retirement assets. This is not a marginal optimization — it is one of the highest-value financial planning decisions a retiree can make.
This article is for educational purposes only and does not constitute financial, tax, or legal advice. Consult a qualified professional for guidance specific to your situation.