What Is Tax Alpha? How Tax-Loss Harvesting and Custom Indexing Can Add Value to Your Taxable Accounts

If you hold investments in a taxable, non-qualified brokerage account (as opposed to an IRA or 401(k)), how you manage the tax side of that account can matter almost as much as what you own inside it. That added value, the extra after-tax return you capture through tax-aware management rather than through picking better stocks or timing the market, is what we mean by "tax alpha."

Tax alpha only applies to taxable accounts. Inside an IRA, Roth IRA, or 401(k), buying and selling doesn't trigger a current-year capital gain or loss, so there's nothing to harvest. But in a taxable brokerage account, every sale has a tax consequence, and that creates an opportunity. Managed well, that opportunity can meaningfully improve what you actually keep after taxes, year after year.

• Tax alpha is the additional after-tax return generated through tax-aware management of taxable accounts, separate from investment selection or market timing.
• Tax-loss harvesting realizes losses to offset gains elsewhere in your portfolio, and within annual limits, a portion of ordinary income, without necessarily changing your market exposure.
• The wash-sale rule restricts repurchasing a "substantially identical" security too soon after a loss sale; replacement securities need to be chosen carefully.
• Custom indexing (direct indexing) can harvest losses at the individual stock level, even in years when the overall index is up, something a mutual fund or ETF share cannot do.
• Custom indexing tends to make the most sense for taxable portfolios generally $250,000 and above, for investors in higher tax brackets, or for managing a concentrated stock position.
• None of this replaces personalized tax or investment advice. Your tax professional and advisor should weigh in on your specific situation.

Most conversations about portfolio performance focus on gross returns: how the investments themselves performed. Tax alpha looks at a different question: of the return your portfolio generated, how much did you actually keep after taxes, and could smarter tax management have kept more of it?

This is distinct from "alpha" in the traditional sense (outperforming a benchmark through security selection). Tax alpha isn't about picking better investments. It's about managing the tax consequences of the investments you already hold, so that a larger share of your return stays in your pocket rather than going to the IRS.

Again, this only works in taxable, non-qualified accounts. In our experience, clients often focus heavily on asset allocation inside their IRAs and 401(k)s, where tax timing doesn't apply, while leaving meaningful tax alpha on the table inside their taxable brokerage accounts.

Tax-loss harvesting means intentionally selling a security that has declined in value to realize a capital loss. That loss can then be used to offset realized capital gains elsewhere in the portfolio, and within annual limits, a portion of ordinary income as well, with any losses beyond that carried forward to future tax years.

Done properly, tax-loss harvesting doesn't have to change your underlying market exposure. The idea is to sell the position at a loss and promptly reinvest the proceeds in a similar, but not identical, investment, so your portfolio stays invested and aligned with your strategy while the tax loss is locked in.

That "similar, but not identical" requirement exists because of the IRS wash-sale rule, which disallows the loss if you buy back a substantially identical security within the restricted window around the sale. Selecting an appropriate replacement security, one that maintains your intended exposure without running afoul of the wash-sale rule, takes care and experience. We'd encourage you to review the IRS guidance on capital gains and losses and talk with your tax professional and advisor before executing a loss-harvesting strategy on your own.

The practical benefit is straightforward: a lower current-year tax bill means more dollars stay invested and have the opportunity to compound over time, rather than being sent to taxes that could have been deferred or offset.

Traditional index funds and ETFs are efficient, but they have a built-in limitation for tax purposes: you can only harvest a loss on your entire position in the fund. If the fund as a whole is up for the year, there's typically nothing to harvest, even if some of the underlying companies inside that fund have declined.

Custom indexing (also called direct indexing) addresses that limitation. Instead of owning a single share of a fund that tracks an index, you directly own the individual securities that make up that index inside your own account. Because each stock is held separately, each one can be evaluated and harvested for a loss independently, throughout the year, even when the overall index is positive. That ability to harvest at the individual security level, rather than only at the whole-fund level, is one of the most significant ways custom indexing can help generate tax alpha.

Custom indexing also opens the door to personalization that a packaged fund can't offer. You can exclude specific companies or industries you'd rather not hold, tilt toward particular factors, or methodically manage a concentrated single-stock position, all while still aiming to track the broader index's overall performance.

This approach tends to work best for investors with meaningful taxable account balances, generally $250,000 and above, who are in higher tax brackets where the harvested losses carry more value. For smaller taxable balances, or for assets already sitting inside tax-advantaged accounts, the added complexity and cost of direct indexing may outweigh the benefit.

In our experience, the burden of coordinating investment decisions with tax strategy usually falls on the client, which means the left hand doesn't always know what the right is doing. That's part of why Cannon Advisors works alongside our unaffiliated sister firm, Cannon Tax & Accounting, to help connect the dots between your portfolio and your tax picture, rather than treating them as separate conversations.

• Harvesting a loss and immediately repurchasing the same security, triggering the wash-sale rule and disallowing the loss.
• Assuming tax-loss harvesting guarantees a lower tax bill every year; opportunities depend on market conditions and your individual tax situation.
• Pursuing custom indexing on a small taxable balance where added complexity and cost outweigh the tax benefit.
• Overlooking tax-advantaged accounts entirely when thinking about tax alpha; remember, the opportunity exists specifically in taxable accounts.
• Making tax-loss harvesting decisions in isolation, without considering your overall portfolio allocation, cost basis, and long-term goals.

Every investor's tax situation and account structure is different. If you have meaningful assets in a taxable brokerage account and want to understand whether tax-loss harvesting or custom indexing could be a fit for your portfolio, we'd welcome the conversation. Schedule a call with us to talk through your specific situation.

Does tax alpha apply to my IRA or 401(k)? No. Tax alpha specifically applies to taxable, non-qualified brokerage accounts, since trades inside an IRA or 401(k) don't create a current-year capital gain or loss.

Is tax-loss harvesting guaranteed to save me money every year? No. The benefit depends on market conditions and your individual tax circumstances. In a year where few or no positions have losses, there may be limited opportunity to harvest.

What is the wash-sale rule? It's an IRS rule that disallows a tax loss if you buy a substantially identical security within a restricted window around the sale. See IRS Publication 550 for details.

Does tax-loss harvesting change what I'm invested in? When done properly, the goal is to maintain similar market exposure by reinvesting proceeds into a comparable, but not identical, investment.

What is custom indexing or direct indexing? It's an approach where you directly own the individual securities that make up an index, rather than owning a single fund share, allowing loss harvesting at the individual stock level.

How is custom indexing different from owning an index ETF? With an ETF, you can only harvest a loss on your whole fund position. With custom indexing, each underlying stock can be evaluated and harvested separately.

How much do I need to benefit from custom indexing? It tends to work best for taxable portfolios generally $250,000 and above, particularly for investors in higher tax brackets.

Can custom indexing track an index exactly? It aims to track the broader index, but because it may exclude or tilt certain holdings, there can be tracking error relative to the benchmark.

Are there extra costs with custom indexing? It can involve higher costs than a traditional index fund or ETF, which is part of why it tends to make the most sense for larger taxable balances.

Is this tax advice? No. This article is general education, not individualized tax or investment advice. Please consult your tax professional and advisor about your specific situation.

• IRS, Topic No. 409, Capital Gains and Losses
• IRS, Publication 550, Investment Income and Expenses (Wash Sales)

Tax-loss harvesting benefits are not guaranteed and depend on market conditions and individual tax circumstances. Custom indexing involves direct ownership of individual securities and may result in tracking error relative to the benchmark; it can involve higher costs than traditional index funds or ETFs. Diversification does not ensure a profit or protect against loss. Past performance is not indicative of future results. This article is general education, not individualized tax or investment advice.