Should you tax-loss harvest a stock you love?

This is a genuinely hard question for stock‑pickers.

Let’s say you’re incredibly bullish on a company.

The stock is down.

You could:

• Sell it
• Capture the loss
• Wait 30+ days to avoid the wash-sale rule
• Then buy it back

But what if it rallies during that 30‑day window and you miss the rebound?

This is the problem with picking individual stocks.

You’re attached to the stock.

As a systematic investor, I don’t care about any individual stock.

We’re long (and short) hundreds of securities at any given time.

There is no emotion involved. Just math.

We:

• Buy stocks with characteristics we believe are attractive
• Short ones with unfavorable characteristics

Then we layer taxes on top of that process and ask:

“What portfolio maximizes expected after-tax wealth?”

Sometimes that means harvesting a loss.

Sometimes it doesn’t.

A stock may be down significantly and still be such an attractive opportunity that the model chooses not to sell it.

Other times there may be multiple securities with similar expected returns, allowing us to harvest a loss while maintaining nearly identical exposure.

If you’re still doing bottom‑up stock‑picking in a taxable account, the “harvest vs hold” question is almost impossible to solve cleanly.

If you treat stocks as inputs to a model instead of your identity, you can optimize for what actually matters:

The after‑tax return of the whole portfolio, not whether you nailed one ticker.