Tax-Efficient Withdrawal Order in Retirement — Which Account to Drain First

Most retirees follow the path of least resistance: withdraw from whatever account is easiest to access, or drain the biggest bucket first. Yet withdrawal sequence is one of the most powerful tax-planning levers available in retirement. Over a 30-year horizon, choosing the wrong order can cost six figures in taxes—or net you an equal windfall by making strategic moves in early retirement years when tax brackets feel empty and Roth conversions unlock tax-free growth.

The conventional wisdom sounds logical: tap taxable accounts first (to defer tax-deferred growth), then traditional IRAs, then Roths last. But conventional wisdom ignores the multivariate reality of modern retirement: required minimum distributions (RMDs), Medicare Income-Related Monthly Adjustment Amounts (IRMAA), Social Security provisional income thresholds, net investment income tax (NIIT) triggers, and the permanent value of tax-free growth in Roth accounts.

Why Withdrawal Order Matters More Than People Think

The order in which you pull money from taxable, traditional, and Roth accounts determines which dollars get taxed at what rate, which buckets grow tax-free for longer, and whether your income triggers secondary taxes or benefit reductions you didn't anticipate. Early withdrawal decisions ripple forward: a $40k traditional IRA distribution at 64 might bump you into the IRMAA threshold that year, raising Medicare premiums for three years (through 65). The same $40k pulled from a Roth—or avoided altogether through a pre-RMD Roth conversion—costs nothing in extra premiums.

A second layer: Social Security benefits are taxed based on provisional income, which includes IRA withdrawals dollar-for-dollar but Roth withdrawals not at all. Similarly, long-term capital gains and qualified dividends from taxable accounts sit in the 0%, 15%, or 20% brackets (depending on ordinary income), while distributions from a traditional IRA land as ordinary income and fill the lower brackets first, pushing gains into higher brackets by displacement.

The Conventional Playbook: Taxable, Then Traditional, Then Roth

The traditional sequencing rule originated in the era of IRAs and taxable accounts. The logic was twofold: first, tax-deferred money should compound as long as possible. Second, taxable accounts already suffered one layer of tax (on contributions), so pull them first to avoid double taxation. Third, Roths should be protected at all costs because they compound forever tax-free.

This framework works adequately when income sources are simple (pension plus Social Security) and account sizes are modest. But it breaks down at higher net worth or when RMDs are looming. If you're 72 and forced to take a $50k RMD from your $800k traditional IRA regardless, there's no benefit to "preserving" it by withdrawing from taxable first. You'll pay tax on the RMD anyway. Meanwhile, pulling $50k from a taxable account at long-term capital gains rates (0%, 15%, or 20%) might be cheaper than the 24% or 32% ordinary income rate applied to the RMD.

Worked Example: The 63-Year-Old Early Retiree

Meet Sarah, 63, with no earned income and retirement savings of $480k in a taxable brokerage account, $720k in a traditional IRA (from a 401k rollover), and $310k in a Roth IRA. She needs $70k per year to live on, indexed for inflation. Her full Social Security (at 67) will be $32k annually. Her taxable account has $120k in unrealized gains. She wants to retire today.

Under the conventional approach, Sarah would withdraw $70k from her taxable account in year one. She'd trigger long-term capital gains tax on roughly $18k of gains (proportional to her cost basis), paying ~$2,700 in federal tax (assuming 15% rate, 2.3% NIIT, no state tax). By age 72, her taxable account is depleted, and she's forced onto traditional IRA withdrawals. At 73, RMDs begin at roughly 3.65% of her prior year-end balance—about $26k, plus her living expenses demand another $44k, totaling $70k from the traditional IRA. That $70k is fully ordinary income, taxed at 24% federal rate ($16,800), even though her ordinary income threshold for IRMAA is only $194k (in 2026).

The Smarter Play: Tax-Bracket Filling and Pre-RMD Conversions

Sarah's smarter move exploits the tax gap between now and RMDs. From ages 63–72, she has a 9-year window before RMDs are mandatory. Her ordinary income in those years is zero (no W-2 wages, no IRA withdrawals, no pension). She has full access to the 12% and 22% federal brackets, which in 2026 span roughly $0–$22,750 (single filer) and $22,751–$91,250, respectively.

Sarah's new strategy: withdraw $35k per year from her taxable account (not $70k), and convert $35k per year from her traditional IRA to her Roth IRA. The conversion triggers ordinary income tax on the full $35k at her marginal rate. In years 1–3, she remains in the 12% bracket, paying ~$4,200 in tax per year. In years 4–9, the conversion amount ($35k) spans the 12% and 22% brackets, paying roughly $5,950 in tax per year. Total conversion tax over 9 years: ~$56,700.

Compare the outcomes at age 73. Under the conventional approach, her traditional IRA has shrunk to ~$600k (after 9 years of RMD withdrawals at ≈3.65%, plus the $44k annual draws). Her taxable account is emptied. Her RMD at 73 is ~$21,900, all ordinary income, taxed at her marginal rate (likely 24% given Social Security income), costing ~$5,250 in tax. Plus, she withdraws another $48k from her traditional IRA, fully taxable at 24%, costing ~$11,500.

Under Sarah's conversion strategy, her traditional IRA has shrunk to ~$435k (after 9 years of $35k conversions + $35k taxable withdrawals, but no RMD burden). Her taxable account still has ~$120k remaining. Her Roth IRA has swollen to ~$625k. At 73, her RMD from the traditional IRA is only ~$15,900. She withdraws an additional $54k from her taxable account (at long-term capital gains rates, paying ~$3,200 in tax). No Roth withdrawal is needed.

The IRMAA and Social Security Trap

The conversion strategy gains a third advantage once Sarah begins Social Security at 67. Her provisional income (adjusted gross income plus tax-exempt interest plus half of Social Security benefits) determines Medicare premiums via IRMAA brackets. In 2026, the first IRMAA threshold for singles is $194k. Traditional IRA withdrawals boost provisional income dollar-for-dollar. Roth conversions also count as ordinary income that year, but in Sarah's case, she's paying conversion tax in years when Social Security hasn't started, so the conversion cost is pure federal income tax (12%–22%), not inflated by IRMAA.

Once Social Security flows at age 67, Sarah's provisional income includes $32k (her benefit) plus her withdrawal income. Under the conventional strategy, at 72 she'd be pulling $44k from her traditional IRA, plus $32k Social Security, plus $15k taxable account income (~$5k gains)—totaling ~$91k in provisional income. Under the conversion strategy, she's pulling $35k from taxable account plus $32k Social Security (1.5% NIIT applies to her gains), avoiding the traditional IRA withdrawal and keeping provisional income under $75k, staying below the first IRMAA threshold and saving $432/year per person in Medicare premiums.

Asset Location: Bonds in Traditional, Growth in Roth

A second tactical layer: where you place which asset classes matters. Bonds generate ordinary income (fully taxed in taxable accounts). Stocks generate qualified dividends and long-term gains (taxed at 0%–20%, much lower). Roth accounts compound tax-free forever, so they should host the highest-growth assets. The reverse order—bonds in Roth, stocks in taxable—wastes the Roth's tax-free compounding.

Sarah should rebalance: hold bonds, bond funds, and real estate investment trusts (REITs) in her traditional IRA where their ordinary income is sheltered. Hold growth stocks, index funds, and emerging markets in her Roth, where 30 years of compounding escapes all taxation. Her taxable account holds a mix, but dividend-heavy positions favor dividend aristocrats (lower yield, lower tax drag) over high-yield bonds or REITs.

The Mechanics: When RMDs Begin

At 73, Sarah is subject to RMDs from her traditional IRA. The RMD is calculated as the prior year-end balance divided by the IRS life expectancy factor. If her balance is $435k at age 72, her age-73 RMD is roughly $15,900. She must withdraw this; she cannot skip it. She can, however, direct her RMD to a charity via a qualified charitable distribution (QCD) if she itemizes, or she can strategically withdraw the RMD plus additional amounts to fill her tax bracket, converting excess to Roth if beneficial.

Roth IRAs have no RMD during the account holder's lifetime, so Sarah's $625k Roth can sit and compound untouched through her 80s and 90s. This makes the Roth the ultimate "legacy" bucket: money that grows, never shrinks, and passes to heirs tax-free.

The Net Investment Income Tax Wildcard

Sarah is subject to the 3.8% net investment income tax (NIIT) on long-term gains and qualified dividends if her modified adjusted gross income exceeds $200,000 (single filers). This doesn't apply to her until Social Security and substantial distributions push her income well above that threshold. However, in her early 70s, when she's drawing from both her taxable account and taking larger traditional IRA withdrawals before RMDs compress her flexibility, NIIT can silently inflate her tax burden. A $50k withdrawal from taxable brokerage plus $20k Social Security plus $25k IRA distribution = $95k provisional income, but it also triggers NIIT on the investment gains in the taxable account, adding 3.8% to her effective tax rate.

The conversion strategy mitigates this by frontloading conversions (in years 1–6) when Social Security hasn't started and NIIT isn't a factor. By the time Social Security arrives, conversions are done, and Sarah's later years see smaller traditional IRA draws, smaller NIIT exposure, and higher Roth balance to absorb living needs tax-free.

Putting It All Together: A Realistic Withdrawal Calendar

Here's Sarah's full calendar using the conversion strategy. Ages 63–66: withdraw $35k/year from taxable (paying ~$2,100/year in long-term gains tax), convert $35k/year from traditional IRA to Roth (paying 12% conversion tax, ~$4,200/year). Ages 67–72: continue the same, but now Social Security flows in, and IRMAA applies to the conversion income—she'll pay an extra ~$200/year in Medicare premiums on the conversion, but still saves money vs. withdrawing from traditional IRA. At 73, RMD kicks in at ~$15,900; she takes this, plus converts another $25k from traditional to Roth (filling into the 22% bracket), for a total traditional distribution of ~$40k, paying ~$6,000 in tax. Ages 74+: RMDs continue to rise; she takes RMD plus minimal additional traditional draws, relying primarily on taxable account and Roth withdrawals (Roth withdrawals are always tax-free).

By age 80, Sarah's taxable account has depleted (but she's paid only ~$2,100/year in gains tax, much lower than if she'd drained it in year 1). Her traditional IRA is down to ~$350k and paying ~$12k/year in RMDs. Her Roth is now $700k and can fund the remainder of her spending forever tax-free. Compare this to the conventional strategy: her traditional IRA would be heavily depleted by age 72 (forcing large RMDs and high ordinary income tax), her taxable account would be gone, and only a depleted Roth remains.

The total tax paid by age 80 under the conversion strategy is roughly $290k (conversions during low-bracket years: $56,700 + gains tax from taxable account: ~$90k + RMD taxes: ~$144k). Under the conventional approach, it's roughly $380k. The conversion strategy nets Sarah ~$90k in tax savings over 17 years—a meaningful boost to her retirement standard of living and legacy.