Asset location: which investments belong in which account
Asset allocation answers how much you hold in stocks versus bonds. Asset location answers a quieter question: once you have picked that mix, which account should hold which piece? The same portfolio can produce meaningfully different after-tax wealth depending on whether the bonds sit in your 401(k) or your brokerage account, because the three big account types tax growth in completely different ways.
Three buckets, three tax treatments
A taxable brokerage account is taxed as you go: interest and non-qualified dividends are taxed every year at ordinary rates (up to 37% for 2026), while qualified dividends and long-term capital gains get preferential rates — 0%, 15%, or 20% depending on income. For 2026, the 0% rate applies up to $49,450 of taxable income for a single filer and $98,900 for a joint return, and the 15% rate runs to $545,500 and $613,700. High earners may also owe the 3.8% net investment income tax once modified adjusted gross income passes $200,000 single or $250,000 joint — thresholds fixed by statute, not indexed. Crucially, capital gains in a brokerage account are taxed only when you sell, and unrealized gains disappear entirely at death under the step-up in basis.
A pre-tax account (traditional 401(k) or IRA) defers everything — no tax on dividends, interest, or trading inside the account — but every dollar withdrawn is ordinary income, and required minimum distributions eventually force those withdrawals. A Roth account is the mirror image: no deduction going in, but growth and qualified withdrawals are never taxed at all.
What makes a holding tax-inefficient
The classic candidates for shelter are assets that throw off ordinary income every year: taxable bonds and bond funds, REITs (whose dividends are mostly non-qualified), and anything you trade frequently. Held in a brokerage account, they generate a tax bill annually with no way to defer it. Held inside a 401(k) or IRA, that annual drag vanishes.
Broad stock index funds are the opposite: they distribute modest dividends (mostly qualified), rarely distribute gains, and let appreciation compound untaxed until you choose to sell — at preferential rates when you do. They lose relatively little by sitting in a taxable account, which is why the conventional ordering is: bonds and REITs in pre-tax, highest-expected-growth assets in Roth, and tax-efficient stock funds in taxable.
Why Roth gets the growth
Think of a pre-tax account as jointly owned with the IRS: if your retirement marginal rate is 24%, roughly a quarter of that balance was never really yours. Every dollar of growth in pre-tax is growth on the government’s share too — and fast growth there also inflates future RMDs, which arrive as forced ordinary income whether you need it or not. Growth in a Roth is 100% yours forever. So when you decide where the aggressive slice of the portfolio lives, Roth first is the usual answer, with pre-tax holding the slow-growing, ordinary-income-producing assets that would be taxed heavily anywhere else.
The caveats that change the answer
Asset location is a second-order optimization, and the ordering can flip. When bond yields are low, the cost of holding bonds in taxable is small. A retiree whose taxable income sits under the 0% capital-gains threshold ($98,900 joint for 2026) pays nothing on gains and qualified dividends anyway, so sheltering stocks buys little. Municipal bonds are already federally tax-exempt and belong in taxable if you hold them at all. And location should never override allocation: do not hold a riskier portfolio than you want just to fill tax buckets elegantly. Get the mix right first, place it second.
Try it in Deorbit Plan
Deorbit Plan models each bucket’s tax mechanics separately: the Accounts panel takes your taxable balance with its cost basis, plus pre-tax, Roth, and HSA balances. The engine taxes brokerage dividends every year, uses your basis to compute the taxed gain share of each taxable withdrawal (with LTCG stacking and NIIT), and treats every pre-tax dollar as ordinary income on the way out. Watch the Account buckets chart to see how the mix shifts over retirement, and reorder the withdrawal sequence in the Strategy panel to see how draining tax-inefficient buckets earlier or later changes lifetime taxes on the Taxes & MAGI chart.
Educational content only — not financial, tax, or investment advice.
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