Retirement Income Sequencing Across Account Types: A Guide for Multi-Account Retirees

Who This Guide Is For, and Why the Standard Advice Falls Short

If you are within about five years of retiring, or already retired, with money split across a 401(k) or traditional IRA, a Roth IRA or Roth 401(k), and a regular taxable brokerage account, this guide is written for you. It is also relevant if you have a pension or pending Social Security benefit layered on top, since those fixed income streams change how much room you have left in each tax bracket for discretionary withdrawals.

The old rule of thumb sounds simple: drain taxable accounts first, then traditional pretax accounts, then Roth accounts last. That ordering delays taxes as long as possible, which sounds like good planning. In practice, treating it as a rigid sequence rather than a flexible framework creates a predictable problem. Traditional account balances keep compounding tax-deferred while you avoid touching them, so by the time required minimum distributions begin, the balance is larger and the mandatory withdrawal is larger too. A retiree who spent a decade in the 12% bracket by living entirely off taxable savings can walk into their RMD years and discover the forced withdrawal alone pushes them into the 22% or 24% bracket, adds a Medicare premium surcharge, and makes more of their Social Security benefit taxable in the same year.

This is not a hypothetical edge case. It is close to the median outcome for savers who did the right thing during their working years — maxing out a 401(k) match, then contributing more to pretax accounts because the immediate deduction felt good — and who now hold most of their net worth in accounts the IRS eventually forces them to unwind on its own schedule. Sequencing decisions made in the first five to ten years of retirement determine whether that unwind happens gradually and cheaply, or all at once and expensively.

The Three (or Four) Buckets and How Each One Is Actually Taxed

Before sequencing anything, it helps to be precise about what each account type does at the moment of withdrawal, because the differences are not just “taxed” versus “not taxed.”

Taxable brokerage accounts

Withdrawing from a taxable account is not really a taxable event by itself — you already paid income tax on the money you put in. What is taxable is realized capital gains and dividends. If you sell appreciated shares, only the gain over your cost basis is taxed, typically at long-term capital gains rates of 0%, 15%, or 20% depending on your total taxable income, and that gain often stacks on top of your ordinary income for bracket purposes. Many retirees are surprised to learn there is a real 0% capital gains bracket: for 2026, a single filer with taxable income roughly under the mid-$49,000s, or a married couple filing jointly under roughly $99,000, can realize long-term gains at a 0% federal rate. That window is one of the most underused tools in retirement income planning.

Traditional 401(k), 403(b), and IRA accounts

Every dollar withdrawn from a traditional account is taxed as ordinary income in the year you take it, regardless of whether the underlying growth came from contributions, dividends, or capital appreciation inside the account. There is no capital gains treatment once money is inside a traditional account — it all converts to ordinary income on the way out. These accounts also carry required minimum distributions once you reach the applicable RMD age, currently 73 for anyone who turned 72 after 2022, stepping up to 75 in 2033 for people born in 1960 or later. RMDs are not optional and the penalty for missing one is steep: 25% of the shortfall, reduced to 10% if corrected within roughly two years.

Roth IRA and Roth 401(k) accounts

Qualified withdrawals — meaning the account has been open at least five years and you are 59½ or older, disabled, or a qualifying first-time homebuyer for the IRA version — come out completely free of federal income tax, principal and growth alike. Roth IRAs carry no RMDs during the original owner’s lifetime. Roth 401(k)s did carry RMDs until the SECURE 2.0 Act eliminated that requirement starting in 2024, which removed one of the last practical disadvantages of keeping Roth money inside an employer plan rather than rolling it to a Roth IRA.

Health Savings Accounts, the quiet fourth bucket

An HSA is arguably the single most tax-efficient account in the entire system for the specific job of paying medical bills: contributions are pretax (or tax-deductible), growth is tax-free, and qualified withdrawals for medical expenses are tax-free at any age. After 65, non-medical withdrawals are taxed like a traditional IRA — ordinary income, no penalty — which makes an HSA a flexible backstop that behaves like a Roth for healthcare spending and like a traditional account for everything else.

The Conventional Withdrawal Order, and the Cases Where You Should Break It

The textbook sequence — taxable, then traditional, then Roth — makes sense as a default because it lets tax-deferred and tax-free growth compound the longest. It is the correct starting assumption for someone with a small traditional balance relative to their taxable and Roth holdings, because there is little risk of a future RMD problem.

The sequence breaks down for three common situations:

• A large traditional balance relative to total assets. If your 401(k) and IRAs make up the bulk of your net worth, refusing to touch them early just delays a bigger reckoning at RMD age. In this case, taking modest, bracket-aware traditional withdrawals — or doing Roth conversions of the same size — during the low-income years right after retirement (and before Social Security and RMDs both start) is usually the more tax-efficient path.
• A gap between retirement and Social Security or pension start. Years where your only taxable income might otherwise be near zero are the cheapest years you will ever have to realize traditional income or execute Roth conversions, because you can fill the 10%, 12%, and 22% brackets with money that would otherwise be taxed at 22%, 24%, or higher once RMDs and Social Security stack together later.
• A need to manage Medicare IRMAA thresholds. Because Medicare Part B and Part D premium surcharges are based on modified adjusted gross income (MAGI) from two years earlier, a single unusually large withdrawal or Roth conversion can raise your premiums for a full year, two years later, even if your income returns to normal immediately. Retirees within two years of enrolling in Medicare need to plan withdrawals with that look-back in mind, not just current-year brackets.

None of this means abandoning the general “spend taxable first” instinct. It means treating each account as a lever you pull by a specific, deliberate amount every year rather than an on/off switch you flip once and never revisit.

How RMDs, IRMAA, and the Social Security Tax Torpedo Interact

The mechanics above become a genuine planning problem only because several thresholds interact rather than acting independently. A dollar of extra traditional withdrawal can, in the same tax year, push you into a higher marginal bracket, make more of your Social Security benefit taxable, and raise your Medicare premiums two years later. Understanding each piece separately is what lets you plan around the combination.

The Social Security “tax torpedo”

Up to 85% of Social Security benefits can be subject to federal income tax, based on “combined income” (adjusted gross income, plus tax-exempt interest, plus half your Social Security benefit). The thresholds that trigger this — $25,000 and $34,000 for single filers, $32,000 and $44,000 for married couples filing jointly — have never been adjusted for inflation since they were set in 1983 and 1993. That means more retirees cross them every year simply because of ordinary cost-of-living increases, and every extra dollar of traditional withdrawal in that zone can effectively make $1.50 of income taxable, which is why planners call it a torpedo: the effective marginal rate spikes well above your regular bracket for a range of income, then falls back down once 85% is fully phased in.

IRMAA surcharges

Medicare IRMAA adds a surcharge to Part B and Part D premiums for higher-income beneficiaries, assessed in tiers rather than smoothly. In recent years the first tier began around $106,000 of MAGI for single filers and roughly $212,000 for married couples filing jointly, with the exact dollar cutoffs adjusted annually for inflation. Because the surcharge is a cliff rather than a gradual phase-in — crossing a threshold by even one dollar triggers the full higher tier for that bracket — a large one-time Roth conversion or a lumpy capital gain in the “wrong” year can cost far more than the marginal tax rate alone would suggest.

Required minimum distributions

RMDs are calculated by dividing your prior year-end traditional account balance by an IRS life expectancy factor from the Uniform Lifetime Table. The withdrawal amount is not something you can reduce once it starts — it only grows in dollar terms as your account balance and your age both increase — which is exactly why proactively shrinking the traditional balance in the years before RMDs begin, through spending or conversions, is the main lever retirees have to control their own future tax bill.

Roth Conversions as an Ongoing Sequencing Tool

A Roth conversion is not really a separate strategy from withdrawal sequencing — it is the same lever used differently. A withdrawal from a traditional account that you spend is ordinary income you consume. A withdrawal from a traditional account that you convert to a Roth is ordinary income you redirect into a tax-free bucket for later. Both create a taxable event this year; only one of them keeps growing tax-free afterward.

The years most retirees should look hardest at conversions are the ones between when full-time work income stops and when Social Security and RMDs both start pulling income back up — often a five-to-ten-year window in the early sixties to early seventies. Filling the 12% and 22% brackets with conversions in those years, rather than leaving that bracket space unused, is one of the more reliably profitable moves in retirement tax planning, assuming you have outside cash (from a taxable account) to pay the conversion tax bill without touching the converted funds themselves.

The catch is that conversions are irreversible under current law — the “recharacterization” option that once let you undo a conversion was eliminated by the 2017 tax law for conversions after 2017. That makes sizing the conversion correctly each year, rather than converting an entire account at once, the more disciplined approach: convert up to the top of a target bracket, stop, and reassess next year based on updated income, market performance, and legislative changes.

Worked Example: Sequencing a $1.5 Million Portfolio Across Three Account Types

Consider Janet, 63, recently retired, married filing jointly, with no pension and Social Security deferred until 67. Her portfolio: $850,000 in a traditional 401(k) rolled to an IRA, $350,000 in a Roth IRA, and $300,000 in a taxable brokerage account with roughly $120,000 of embedded long-term capital gains. Her household needs $85,000 a year, after tax, to cover spending.

In her first four years of retirement, before Social Security starts, her only taxable income comes from whatever she chooses to withdraw. If she followed the rigid conventional order and spent taxable dollars exclusively, she would owe modest capital gains tax and stay in a very low bracket — but her traditional IRA, left untouched and continuing to grow, would balloon toward $1.1–1.2 million by age 73, forcing an RMD well above $45,000 in its first year alone, stacking on top of Social Security and pushing her into a materially higher bracket for the rest of her retirement, with a real chance of triggering IRMAA.

The bracket-filling alternative: Janet spends primarily from her taxable account for day-to-day cash flow, exactly as the conventional order suggests, but she also converts roughly $45,000–$55,000 per year from her traditional IRA to her Roth IRA during these four low-income years — enough to fill up the 12% bracket and stay just inside the 22% bracket, without tipping into higher brackets or anywhere near an IRMAA threshold. She pays the conversion tax from the same taxable account. By the time Social Security starts and RMDs eventually arrive, her traditional balance is meaningfully smaller, her Roth balance is meaningfully larger, and her RMD-driven income is far more manageable relative to her other income sources.

Account Types Compared: Tax Treatment, RMDs, and Sequencing Role

Withdrawal Order Strategies Compared

Common Sequencing Mistakes That Cost Multi-Account Retirees Thousands

• Treating “taxable, then traditional, then Roth” as a permanent rule instead of a default. It is the right starting point, not a rule that should survive contact with your actual RMD projections.
• Ignoring the years before Social Security and RMDs begin. These low-income years are the cheapest opportunity most retirees will ever have to convert or realize income, and once they pass, they do not come back.
• Converting a round, arbitrary amount instead of the amount that fills a specific bracket. Converting “$50,000 because it sounded reasonable” instead of calculating the exact dollar amount that fills the current bracket without spilling into the next one leaves money on the table or, worse, overshoots into a materially higher rate.
• Forgetting the two-year IRMAA look-back. A large conversion or capital gain the year before Medicare enrollment, or during Medicare, can raise premiums two years later — after the income that triggered it is long gone.
• Not coordinating withdrawals with a spouse’s separate accounts. Married couples often optimize each spouse’s accounts independently instead of treating the household’s combined tax return as the single unit that actually matters.
• Selling the wrong taxable lots. Selling high-basis shares first when low-basis shares would have realized a smaller gain (or vice versa, when tax-loss harvesting is available) is a simple, avoidable cost.
• Overlooking Qualified Charitable Distributions. For retirees 70½ or older who give to charity anyway, directing IRA money straight to a qualified charity — up to roughly $110,000 annually as of 2026, an amount now indexed for inflation under SECURE 2.0 — satisfies part or all of an RMD without it ever counting as taxable income.

Your Year-by-Year Sequencing Checklist

• Project your traditional account balance forward to your RMD age and estimate the first-year RMD in today’s dollars — this single number tells you whether you have a future bracket problem.
• Identify your “gap years” between retirement and the later of Social Security start or RMD age, and treat them as your primary conversion or bracket-fill window.
• Calculate, each January, how much room remains in your target tax bracket after Social Security, pension, dividends, and interest are accounted for.
• Fill that remaining room with either a traditional withdrawal (if you need the cash) or a Roth conversion (if you do not).
• Check your projected MAGI against IRMAA thresholds before finalizing any year-end conversion, especially if you are within two years of Medicare enrollment.
• Review which taxable-account lots you would sell, prioritizing tax-loss harvesting opportunities and long-held, low-basis shares in 0% capital gains bracket years.
• Confirm whether a Qualified Charitable Distribution can offset part of this year’s RMD if charitable giving is already part of your plan.
• Revisit the entire sequence annually — market performance, tax law changes, and life events (health, widowhood, moving states) all change the optimal order.

Getting the yearly bracket math right matters just as much as getting the account order right, and it connects directly to the broader question of how fast you can safely spend down the whole portfolio; our guide to safe retirement withdrawal rates walks through how withdrawal-rate assumptions and sequencing decisions reinforce each other over a multi-decade retirement.

Key Takeaways

• The “taxable, then traditional, then Roth” order is a reasonable default, not a rule to follow blindly for thirty years.
• Large traditional balances create a future RMD problem that is cheapest to solve in the low-income years before Social Security and RMDs both start.
• Roth conversions and traditional withdrawals are the same lever aimed at different destinations — one funds spending now, the other prepays taxes for tax-free growth later.
• Social Security taxation and Medicare IRMAA surcharges are threshold-based, not smooth, so a single oversized withdrawal can cost far more than its marginal tax rate suggests.
• HSAs and Qualified Charitable Distributions are underused tools that reduce taxable income without touching the core three-account sequence.
• Revisit the plan every year — the correct sequence shifts with markets, tax law, and your own changing income sources.

Frequently Asked Questions

What is the best withdrawal order for retirement accounts?

For most retirees with taxable, traditional, and Roth accounts, spending from taxable savings first while filling remaining low tax brackets each year with either traditional withdrawals or Roth conversions — and preserving Roth funds for later years — produces lower lifetime taxes than mechanically draining each bucket in a fixed order.

Should I withdraw from my 401(k) or my Roth IRA first in retirement?

If you have a taxable brokerage account, spend that first in most years. Between a 401(k) and a Roth IRA specifically, draw from the 401(k) up to the top of your target tax bracket, and reserve Roth withdrawals for amounts above that bracket or for years when you specifically need to avoid raising your taxable income, such as the two years before Medicare enrollment.

How do required minimum distributions affect withdrawal sequencing?

RMDs force taxable income out of traditional accounts starting at age 73 (75 for those born in 1960 or later), regardless of whether you need the cash. Because that forced income can push you into a higher bracket, trigger taxation on more of your Social Security benefit, or cause a Medicare IRMAA surcharge, many retirees intentionally shrink their traditional balance before RMDs begin through withdrawals or Roth conversions in the years leading up to that age.

Do Roth 401(k) accounts have required minimum distributions?

No. The SECURE 2.0 Act eliminated RMDs for Roth 401(k) and Roth 403(b) accounts starting in 2024, aligning their treatment with Roth IRAs, which have never required RMDs for the original account owner.

How does a Roth conversion affect Medicare premiums?

Medicare Part B and Part D premiums include an income-related surcharge, IRMAA, based on modified adjusted gross income from two years earlier. A large Roth conversion this year can raise your Medicare premiums for a full year, two years from now, even though your income in that later year may be much lower.

References

• Internal Revenue Service — Required Minimum Distribution rules and the Uniform Lifetime Table
• Internal Revenue Service — Topic on the taxability of Social Security benefits
• Centers for Medicare & Medicaid Services — Medicare Part B and Part D Income-Related Monthly Adjustment Amount (IRMAA)
• SECURE 2.0 Act of 2022 — provisions on RMD age changes, Roth 401(k) RMD repeal, and Qualified Charitable Distribution indexing
• Social Security Administration — benefit taxation thresholds and combined income calculation