
How Much Can You Save Annually with Tax-Loss Harvesting?
The most common question about tax loss harvesting is the simplest one: how much does it actually save? The answer is not a single number. It depends on the size of your portfolio, your marginal tax rate, how volatile your holdings are, and — most importantly — how systematically the strategy is executed. But the ranges are real, the math is straightforward, and for most investors with meaningful taxable accounts, the savings are large enough to matter significantly over time.
This article works through the numbers at three different portfolio sizes, explains what drives the variation, and shows what the savings compound into over a decade of consistent execution.
The core mechanic: turning losses into tax dollars
Before the numbers, a quick recap of the mechanism. When you sell an investment at a loss, that realized loss offsets capital gains you have recognized elsewhere in your portfolio. If your gains exceed your losses, you pay tax only on the net difference. If your losses exceed your gains, up to $3,000 of the remaining loss offsets ordinary income, and any balance carries forward to future tax years.
The tax saving from any individual harvest is: loss amount × your marginal tax rate on that gain type. A $20,000 long-term loss harvested against a $20,000 long-term gain, for an investor at the 15% long-term capital gains rate, saves $3,000 in federal tax. The same harvest for an investor at the 23.8% combined federal rate — 20% plus the 3.8% net investment income tax — saves $4,760. The loss is identical. The tax rate is what changes the value.
What drives how much you can harvest
Three things determine how much you can harvest in any given year.
The first is portfolio size. Larger portfolios contain more positions, which means more opportunities for individual holdings to dip below their cost basis at any point during the year. A $500,000 portfolio spread across 30 positions will almost always have several positions showing unrealized losses at any given moment, even in a generally rising market. A $50,000 portfolio with five holdings might go entire years without a harvestable loss large enough to be worth acting on.
The second is market volatility. Harvesting opportunities are created when prices move. A year with significant volatility — sector rotations, rising interest rates, geopolitical shocks — produces more loss positions than a steady, uniformly rising market. 2022 was one of the most productive years for tax loss harvesting in recent memory because virtually every asset class declined simultaneously. Even in strong bull markets, individual positions within a rising index regularly produce harvestable losses as the market rotates between sectors.
The third is execution frequency. Investors who check their portfolios once in December capture only the losses that remain visible at year-end. Investors who monitor continuously capture losses as they emerge throughout the year — including positions that recovered by December and would have shown no harvestable loss in an annual review. Academic research consistently finds that daily monitoring generates two to four times more harvestable losses than annual monitoring across comparable portfolios.
The numbers at three portfolio sizes
$250,000 taxable portfolio
An investor with a $250,000 diversified portfolio of stocks and ETFs, reviewed once annually, might harvest $8,000 to $15,000 in losses in a typical year. At a 15% long-term capital gains rate, that saves $1,200 to $2,250 in federal tax. At the 23.8% combined rate that higher-income investors face, it saves $1,904 to $3,570.
The same portfolio, monitored continuously, typically surfaces $15,000 to $30,000 in harvestable losses across the year. At 23.8%, that is $3,570 to $7,140 in annual federal tax savings — every year, without changing a single investment position.
$1,000,000 taxable portfolio
At $1 million, the math becomes more compelling. Annual monitoring typically surfaces $30,000 to $60,000 in harvestable losses. Continuous monitoring produces $60,000 to $120,000. At the 23.8% combined federal rate that most investors at this portfolio size face, continuous harvesting generates $14,280 to $28,560 in annual federal tax savings.
Add state taxes for investors in high-tax states. A California resident pays up to 13.3% on capital gains on top of federal rates. Their combined marginal rate on long-term gains reaches 37.1%. On $100,000 of harvested losses, that is $37,100 saved — in a single year, from a single strategy, with no change to market exposure.
$2,000,000+ taxable portfolio
At $2 million and above, tax loss harvesting becomes one of the highest-return financial decisions available. Continuous monitoring typically generates $120,000 to $250,000 in harvestable losses annually across a diversified portfolio. At a 23.8% combined federal rate, that is $28,560 to $59,500 in federal tax savings per year. For a California investor at the 37.1% combined rate, the same range produces $44,520 to $92,750 in combined federal and state tax savings annually.
These are not theoretical maximums. They are the ranges produced by systematic, continuous monitoring of a well-diversified portfolio through a normal market year. In a high-volatility year — 2022, 2020, 2018 — the harvestable losses available are substantially larger.
What the savings compound into over ten years
The dollar savings in any single year are significant. What makes tax loss harvesting genuinely transformative is what happens when you treat the saved tax dollars as capital that stays invested.
Consider an investor with a $1,000,000 taxable portfolio who harvests $80,000 in losses per year at a 23.8% combined rate, saving $19,040 annually in federal tax. Over ten years, that is $190,400 in cumulative tax savings. But those savings were not paid to the IRS — they stayed invested, compounding at 7% per year alongside the rest of the portfolio. After ten years, the compounded value of those annual tax deferrals is approximately $263,000.
That $263,000 is not a return generated by picking better stocks or timing the market. It is the direct result of managing the tax layer of the portfolio systematically — a decision that costs nothing in risk, requires no change in investment strategy, and is available to any investor with a taxable account large enough to generate meaningful losses.
The annual monitoring gap: what most investors miss
The difference between annual and continuous harvesting deserves emphasis because it is where most individual investors leave the largest amount of money on the table.
In any given year, a diversified equity portfolio will experience dozens of individual position drawdowns of 5% to 20%, even if the overall portfolio finishes the year up. These drawdowns create harvestable losses that exist for days or weeks before the position recovers. An investor monitoring once in December sees none of them. An investor with continuous monitoring captures each one as it emerges, books the loss, reinvests in a correlated replacement to maintain exposure, and waits for the wash sale window to pass before reestablishing the original position if desired.
Research from Vanguard, Parametric, and multiple academic sources estimates that continuous harvesting generates 0.5% to 1.5% in additional after-tax annual return compared to annual or no harvesting, depending on portfolio size and volatility. On a $1,000,000 portfolio, 1% of additional after-tax return is $10,000 per year — compounding indefinitely, requiring no additional investment, and taking on no additional market risk.
The number that matters most
If there is a single number to carry away from this article, it is this: for a $1,000,000 taxable portfolio managed with continuous, systematic tax loss harvesting, the expected annual federal tax savings at the 23.8% combined rate is approximately $15,000 to $25,000 per year in a typical market year, and meaningfully more in a volatile one.
For investors at this portfolio size who have been doing nothing — or doing a single year-end review — the gap between what systematic harvesting could produce and what they are actually capturing is the most actionable number in their entire financial picture. It is not a marginal improvement. It is a structural, compounding advantage that grows larger every year it is left uncaptured.
The strategy itself is not complicated. The mechanics are well-understood. What has historically been difficult is executing it continuously, across all positions, across all accounts, without triggering wash sales or missing opportunities that appear and disappear within days. That execution problem — not the strategy itself — is what determines how much of the available savings any individual investor actually keeps.