You Have One Household Portfolio, Not One Per Account

Most investors check their accounts the wrong way. The Roth IRA is up 30%, the 401(k) is up 5%, the taxable brokerage is up 18%, the HSA is up 28%. The natural reaction is to rank them and wonder why some accounts are doing so much better than others. Often the answer is simple: those accounts are not separate portfolios. They are different containers for one portfolio.

If your Roth IRA holds 100% global equities and your 401(k) holds a 60/40 mix and your HSA is 100% stocks because you can afford to wait 30 years to use it, the “Roth winning the return race” means the system is working as designed. You allocated more risk to the accounts with the longest horizon and best tax treatment. The market did its job. Your plan did its job. The Roth didn’t outperform; it was holding more equity exposure on purpose.

This guide is the operating manual for thinking that way. The unit of analysis is your household balance sheet, not any individual account. Account labels handle taxes, ownership, access, and contribution rules. The risk and the return are what they are at the household level, regardless of which account holds which fund.

Account Labels Are Wrappers, Not Portfolios

A 401(k), a Roth IRA, a taxable brokerage account, an HSA, a 529, a savings account, and a checking account are not separate financial universes. Each one has different rules: who can contribute, how much, when withdrawals are allowed without penalty, how distributions are taxed, what funds are available, and what happens at death. Those rules matter for implementation. They do not change what a $100 share of a stock index fund actually is.

Markowitz’s 1952 portfolio-choice framework analyzes how wealth is allocated across assets with different expected returns and risks. The Nobel committee summarized his contribution in 1990: “an investor’s portfolio choice can be reduced to balancing two dimensions, i.e., the expected return on the portfolio and its variance.” Nobel Prize in Economic Sciences 1990: Press Release. The portfolio is the unit of analysis. The accounts are wrappers around it. A companion Summitward guide on Modern Portfolio Theory for Real Life works through the math and the marginal-fund-test that follows from this framing.

The After-Tax Wrinkle

A dollar in a traditional 401(k), a dollar in a Roth IRA, and a dollar in a taxable brokerage account are not economically equivalent. The traditional 401(k) dollar is pre-tax: when it comes out in retirement, ordinary income tax reduces it. The Roth dollar is already taxed; it grows and withdraws tax-free. The taxable brokerage dollar is also already taxed but future gains are taxed at capital-gains rates.

William Reichenstein’s After-Tax Asset Allocation in the Financial Analysts Journal (2006) makes this point directly: portfolio analysis should convert assets to after-tax values because the traditional approach fails to distinguish $1 of pre-tax 401(k) money from $1 of after-tax Roth or taxable money. Reichenstein (2006), After-Tax Asset Allocation. If your retirement marginal tax rate will be 22%, then $1,000,000 in a traditional 401(k) is closer to $780,000 of spendable wealth. The Roth and taxable accounts at the same nominal balance are worth more.

The practical implication is that household allocation should be measured two ways: nominal (what the statements say) and after-tax (what you can actually spend). For young accumulators the difference is modest; for late-career savers with large traditional 401(k) balances and Roth conversions on the table, the difference is meaningful.

Human Capital Belongs in the Picture

The household portfolio is bigger than the brokerage statements. Salary, future contributions, RSUs, employer stock, and career capital are real economic exposures. Luis Viceira’s 2001 paper Optimal Portfolio Choice for Long-Horizon Investors with Nontradable Labor Income in the Journal of Finance shows that labor-income risk affects optimal stock allocation. When labor income is relatively stock-like (correlated with the market), optimal equity exposure in financial assets is lower than the standard rule of thumb suggests. Viceira (2001).

For tech workers with RSU-heavy compensation, this is not academic. If your salary, refresher grants, vested stock, career prospects, and local housing market are all tied to the same employer or sector, your “diversified brokerage portfolio” may obscure a household balance sheet dominated by one company. The Summitward guides on Concentration Risk, Human Capital Risk for Tech Workers, and Sell Your RSUs at Vest cover the practical consequences.

The Practical Workflow

The right way to manage a dozen accounts as one portfolio is top-down household policy plus bottom-up account implementation. Five steps:

Inventory every account and liability. Taxable, traditional and Roth IRAs, 401(k), HSA, 529, cash, I Bonds, RSUs and ESPP, real estate, crypto, and major liabilities. Spouse accounts count.
Classify holdings by economic exposure, not account label. Look through mutual funds and ETFs to U.S. stocks, international stocks, bonds (with duration and credit tier), cash, REITs, commodities, and any concentrated single-stock or sector exposure.
Set a household target allocation. Example: 70% global equities, 20% bonds, 5% cash, 5% alternatives. The target is one number for the entire household, not separate targets per account.
Use accounts as implementation sleeves. A Roth IRA can be 100% equity, a 401(k) can hold most of the bonds, a taxable account can hold tax-efficient broad-market ETFs, an HSA can be 100% stocks. The goal is not for each account to look like a target-date fund.
Rebalance with cash flows first. Direct new contributions, dividends, and RSU sale proceeds toward underweight asset classes before selling appreciated taxable positions. Vanguard’s rebalancing guidance describes calendar-based, threshold-based, and combined methods; the underlying mechanic is the same in any of them.

Asset Location: The 80/20 of Tax Efficiency

Once the household allocation is set, place tax-inefficient assets in tax-advantaged accounts and tax-efficient assets in taxable. The general guidance:

Bonds and TIPS: usually best in pre-tax accounts (traditional 401k, traditional IRA). Bond interest is taxed as ordinary income, and shielding that interest inside a pre-tax wrapper preserves the most value.
High-growth equities and REITs: usually best in Roth or HSA accounts. Tax-free growth is most valuable for the highest-expected-return assets.
Broad-market index ETFs: tax-efficient and fine in taxable accounts. They throw off mostly qualified dividends and rarely distribute capital gains.
Active funds, high-turnover strategies, REITs: avoid in taxable accounts when possible.

Reichenstein’s framework is more specific: hold assets subject to ordinary income tax in pre-tax accounts, hold equities (especially passively managed) in taxable accounts, and route the highest-expected-return assets through Roth space. Real households deviate based on plan menu constraints, existing balances, and rebalancing needs. Treat asset location as a 5-year project, not a single trade.

Account-Level Performance Is a Vanity Metric

When asset location is intentional, account returns will differ. The Roth holds equities and rises with the stock market. The traditional 401(k) holds bonds and rises slowly in most years. The HSA holds equities and tracks the Roth. The taxable account is somewhere in between depending on its job. These accounts are not in competition with each other. Comparing the Roth’s return to the 401(k)’s return is like comparing the performance of your stocks to the performance of your bonds: of course the answer differs. That is the diversification working.

Account-level performance is useful for one thing: catching implementation problems. If the Roth is up 5% in a year when global equities returned 22%, something is wrong (high fees, poorly chosen funds, sitting in cash by accident). If the 401(k) is up 5% in a year when global equities returned 22% and the 401(k) is intentionally bond-heavy, that is the portfolio doing its job.

Naive Diversification Is Easy to Do Without Realizing

Shlomo Benartzi and Richard Thaler’s 2001 paper Naive Diversification Strategies in Defined Contribution Saving Plans in the American Economic Review documented a common pattern: 401(k) participants split contributions evenly across the funds offered, regardless of what those funds were. As a result, the proportion invested in stocks depended strongly on the proportion of stock funds in the plan menu, not on the investor’s actual risk tolerance. Benartzi & Thaler (2001). This is the classic 1/n heuristic.

The same dynamic shows up at the household level. A household that owns six target-date funds across six accounts may feel diversified but is actually buying six versions of the same asset mix. The underlying exposures pile up. A household-level X-Ray catches this in a way that account-by-account review does not.

Tools That Help (Briefly)

No single tool does everything. Each solves part of the household-portfolio problem:

Empower Personal Dashboard (formerly Personal Capital): free aggregation across institutions, net worth tracking, asset allocation view, basic investment performance. Strong dashboard, not a tax-adjusted optimizer.
Morningstar X-Ray: deep look-through of fund holdings into asset class, sector, region, style, and individual security influence. Best-in-class for catching hidden overlap.
Fidelity Full View: aggregation focused on Fidelity-centered households. The displayed net worth includes manually entered outside data Fidelity cannot verify.
Sharesight: performance, dividends, tax reporting, and global holdings tracking. Stronger on performance and tax reporting than on planning.
Quicken Simplifi or Quicken Classic: cash flow, budgeting, net worth, investment tracking, and reports. Personal-finance oriented rather than portfolio-theory oriented.
Monarch Money: household financial dashboard, couples-friendly, includes investment-allocation views.
ProjectionLab and Boldin (formerly NewRetirement): long-horizon retirement planning with Monte Carlo, taxes, and goal modeling. Better for scenario planning than day-to-day X-Ray.
Kubera: tracks complex assets including real estate, private equity, crypto, and collectibles. Stronger on balance-sheet breadth than on rebalancing.
Portfolio Visualizer: research sandbox for backtesting, Monte Carlo, factor analysis, and optimization. Best for what-if research, not aggregation.

A workable DIY stack: Empower for aggregation, Morningstar X-Ray for look-through exposure, Portfolio Visualizer for what-if research, and a planning layer (ProjectionLab, Boldin, or Summitward) for goals, taxes, and account types. None of these is required to do the work. A spreadsheet will work too, if maintained.

Try It: The Household X-Ray Calculator

The calculator below collapses up to five accounts into a single household view. It computes both the nominal allocation and the after-tax allocation (discounting pre-tax balances by your expected retirement marginal tax rate). It also flags common asset-location issues: bonds in taxable while Roth holds only equities, or bonds parked in a Roth account where tax-free growth is wasted.

Frequently Asked Questions

If asset location is intentional, why does my Roth IRA matter at all?

It matters as a withdrawal tool, an estate-planning tool, and a tax-rate hedge. Roth balances are tax-free at withdrawal, can be passed to heirs with favorable rules, and protect against higher future tax rates. Asset-location guidance says use Roth space for high-expected-return assets, which means Roth balances should grow faster than pre-tax balances. That growth is the whole point.

What if my 401(k) plan menu is bad?

It is common. A poor 401(k) menu still hosts the employer match (free money) and can hold the bond sleeve in a target date fund or a low-cost bond index. Use other accounts for equities, factor tilts, or assets the plan does not offer. Asset location is a household decision; the 401(k)’s constraints are an implementation detail.

Should both spouses align their accounts identically?

No. Spouses share the household allocation. The accounts can differ. One spouse may have a better 401(k) menu and hold the bonds; the other may have more Roth space and hold the equities. Treat the household as one portfolio; treat each account as a sleeve.

How often should I rebalance across accounts?

Vanguard’s research finds calendar (e.g., annually), threshold (e.g., 5% drift bands), and combined approaches all produce broadly similar long-run outcomes. The practical instruction is to compare your current allocation to your target and bring it back in line. Most households rebalance once a year or when drift exceeds 5 percentage points, whichever comes first. Use new contributions and dividends to rebalance when possible to minimize taxable sales.

How does this fit with goals like a house down payment or college tuition?

Goal buckets and the household allocation are compatible. Cash and short-term bonds for near-term liabilities sit in the cash/bond portion of the household allocation. The 529 for college is part of the household balance sheet. The mistake is treating each goal as a separate portfolio with separate risk targets when the household is the unit that bears risk. Time-horizon matching is real; account-by-account fragmentation is not.

Do I really need software, or will a spreadsheet do?

A spreadsheet is fine if you maintain it. The hardest part of the workflow is the inventory step: getting every account into one place. After that, the math is simple. Aggregation tools save manual work and catch overlap that spreadsheets miss when funds change holdings. If you already have a working spreadsheet, keep it.

Related Guides

Should You Hold REITs? applies this asset-location logic to a single tax-heavy sleeve: where a REIT fund belongs and why.
Should You Count Your Home and Cars in Net Worth? extends the household-balance-sheet view to home and vehicle equity and which numbers fund retirement.
Modern Portfolio Theory for Real Life is the conceptual companion. Once your accounts are aggregated, MPT’s lesson is to evaluate every new fund by its marginal effect on the household portfolio, not on its standalone metrics.
The Asset Allocation Debate works through stock / bond / cash mix decisions for the household-level target.
Concentration Risk covers the math of single-stock and sector concentration inside the household balance sheet.
Human Capital Risk for Tech Workers frames why salary and RSUs already concentrate the household on one employer.
The Order of Investing Operations covers where each new savings dollar should land first across account types.
Tax-Loss Harvesting covers the taxable-account-specific mechanic that the household allocation has to allow for.

Key Takeaways

You have one portfolio, not one per account. Account labels handle taxes, ownership, and access. Risk and return live at the household level.
Account-level performance is usually a vanity metric. When asset location is intentional, the Roth being up 30% and the bond-heavy 401(k) being up 5% is the system working as designed.
$1 in pre-tax, Roth, and taxable accounts are not equivalent. Reichenstein’s after-tax framing discounts pre-tax balances by your expected retirement tax rate.
Human capital and RSUs belong in the picture. Tech-worker households are usually more concentrated in their employer than the brokerage statements show.
Workflow: inventory → classify → set target → implement by sleeve → rebalance with cash flows. Tools help; the workflow is the thing that matters.