Most investors think about asset allocation — the mix of stocks, bonds, and cash. Far fewer think about asset location — which of those investments belongs in which account. Get the location wrong and you can lose 30 to 75 basis points of after-tax return per year, indefinitely. Get it right and the improvement compounds.
The three account types, briefly
- Tax-deferred (traditional 401(k), traditional IRA): contributions are pre-tax; withdrawals are taxed as ordinary income; no taxes along the way.
- Tax-free (Roth 401(k), Roth IRA, HSA): contributions are after-tax; growth and qualified withdrawals are tax-free.
- Taxable (regular brokerage): contributions are after-tax; dividends and realized gains are taxed annually; long-term capital gains and qualified dividends get preferential rates.
The principle
Investments differ in how tax-efficient they are. Bonds generate ordinary-income interest, taxed at marginal rates (up to 37%). Stocks generate qualified dividends and long-term capital gains, taxed at preferential rates (15% or 20%) — and the gains can be deferred indefinitely if you don't sell.
Therefore, the optimal location is roughly:
- Tax-deferred accounts → bonds and high-turnover assets (interest taxed as ordinary anyway, deferral helps)
- Tax-free accounts → highest-expected-return assets (you want maximum compounding in the bucket that never gets taxed again)
- Taxable accounts → tax-efficient stocks and ETFs (qualified dividends, low turnover, deferred gains)
Why most portfolios get this backward
Most retail clients have the same allocation in every account — 60/40 across the board. That's tax-inefficient by design. Bonds in a Roth IRA waste the most valuable tax shelter on the lowest-returning asset. Equities in a taxable account turn over too often, generating unnecessary short-term gains.
The reason it's so common is that platform tools optimize each account independently for risk — not the household across accounts for taxes.
How much it's worth
Vanguard's research has placed the value of correct asset location at roughly 0.20% to 0.75% per year in incremental after-tax return — depending on the household's tax bracket and the proportion of assets across account types.
On a $2M portfolio over 25 years at 0.50% in additional after-tax return, that's roughly $400,000 in additional ending value. From rebalancing the same investments across the same accounts.
When to revisit it
- When you make a large new contribution that meaningfully changes account proportions
- Before and after a Roth conversion
- When asset classes drift far enough to require rebalancing — that's the cheap moment to relocate too
- Annually, alongside the household's overall tax review
Asset location is one of the few unambiguous "free lunches" in investing. It doesn't require a market view, a stock pick, or a forecast. It just requires looking at the household — not the account — as the unit of analysis.
At IronBridge, every household-level review includes an asset-location audit. Get an analysis.