Tax-Loss Harvesting for Small Business Owners with Investment Portfolios

By Yarik Yarosh, CPA ·September 5, 2026 ·4 min read

Written by Yarik Yarosh, CPA (US & Canada) September 5, 2026 · FL CPA license AC61704 · CPA Ontario

Tax-loss harvesting is a strategy for business owners who hold investment portfolios alongside their operating business. The concept is simple: sell investments that are currently at a loss to generate capital losses that offset capital gains (and up to $3,000 of ordinary income per year). The strategy is especially valuable for business owners who realize capital gains from selling business assets, equipment, or real estate.

✓Key takeaway

Tax-loss harvesting basics:

How it works:

Identify investments currently trading below the purchase price (unrealized losses)
Sell those investments to “realize” the loss
Use the realized loss to offset capital gains from other sources
If losses exceed gains: deduct up to $3,000 against ordinary income ($1,500 if MFS)
Remaining losses carry forward indefinitely to future years

The wash sale rule (IRC 1091):

If the taxpayer purchases “substantially identical” securities within 30 days before or after the sale, the loss is disallowed
The 30-day window applies in both directions (30 days before AND 30 days after)
“Substantially identical” means: the same stock, bond, or option, or a contract to acquire the same security
Buying a different fund that tracks the same index is NOT substantially identical (e.g., selling a Vanguard S&P 500 fund and buying a Schwab S&P 500 fund). However, the IRS hasn’t issued definitive guidance on ETFs tracking the same index, so there’s some risk.
The wash sale rule applies across ALL accounts the taxpayer owns (taxable, IRA, Roth IRA, spouse’s accounts)

What to do after selling:

Wait 31 days and repurchase the same security, OR
Immediately purchase a similar (but not substantially identical) security to maintain market exposure
Example: sell a losing position in the Vanguard Total Stock Market ETF (VTI) and immediately buy the Schwab U.S. Broad Market ETF (SCHB). Same market exposure, different security, no wash sale.

When tax-loss harvesting is most valuable for business owners:

The year the owner sells a business asset (equipment, vehicle, building) at a gain
The year the owner sells the business itself (capital gains from the sale)
Years with high ordinary income (the $3,000 deduction against ordinary income saves $720-$1,110 depending on the marginal rate)
Before year-end tax planning (review the portfolio in November-December for harvesting opportunities)

How does tax-loss harvesting interact with asset sales?

Hypothetical example

Round numbers. An S-Corp owner sells a commercial building used in the business. The building was fully depreciated.

Building sale:

Sale price: $500,000
Adjusted basis (after depreciation): $200,000
Capital gain: $300,000
Depreciation recapture (Section 1250, 25% rate): $100,000 x 25% = $25,000
Long-term capital gain: $200,000 x 20% = $40,000
NIIT (3.8%): $300,000 x 3.8% = $11,400
Total tax on building sale: $76,400

Without tax-loss harvesting:

The owner pays $76,400 in tax on the building sale

With tax-loss harvesting: The owner reviews their investment portfolio and identifies:

Stock A: purchased for $80,000, current value $50,000 (unrealized loss: $30,000)
Stock B: purchased for $60,000, current value $45,000 (unrealized loss: $15,000)
Bond fund: purchased for $40,000, current value $35,000 (unrealized loss: $5,000)
Total harvestable losses: $50,000

Step 1: Sell all three losing positions. Realize $50,000 in capital losses. Step 2: Immediately purchase similar (not identical) investments:

Replace Stock A (large-cap growth) with a different large-cap growth fund
Replace Stock B (international equities) with a different international fund
Replace the bond fund with a similar-duration bond fund from a different provider

Tax impact:

Capital gains from building: $300,000
Capital losses from harvesting: ($50,000)
Net capital gain: $250,000
Tax on $250,000 (blended rates): approximately $63,500
Tax saved by harvesting: $76,400 - $63,500 = $12,900

The $50,000 in losses offset $50,000 of the building gain, saving approximately $12,900 in tax.

Multi-year harvesting strategy: If the owner harvests $10,000-$20,000 in losses each year (in years when the portfolio has unrealized losses), the accumulated carryforward can be waiting to offset a large gain event (business sale, real estate sale, equipment sale). Consistent annual harvesting, even in small amounts, creates a “tax loss bank” that can be deployed when needed.

Limitations:

Tax-loss harvesting only defers tax (the repurchased investment has a lower basis, meaning a larger gain when eventually sold)
But if the owner holds the repurchased investments until death: the stepped-up basis eliminates the deferred gain permanently
The strategy has no cost (same market exposure, just a different fund) but requires tracking and avoiding wash sales

Illustrative numbers only, not a real client and not advice for your facts.

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Cite this page

Yarik Yarosh, CPA. "Tax-Loss Harvesting for Small Business Owners with Investment Portfolios." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-tax-loss-harvesting-guide

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.