U.S. Stocks: Sell Highest-Cost Long-Term Lots First to Pay Less Tax?

I learned from ChatGPT that there’s roughly a $47,000 federal tax exemption for long-term capital gains each year (depending on income level and filing status).

Be careful taking tax advice from ChatGPT :)

Federal long-term capital gains tax rates are bracketed just like income tax rates, but the brackets take into account all other income first.

So yes, you can get $47k of long-term capital gains in the 0% tax bracket if you have no other income. If your other income is more than $47k, you fall into the 15% LTCGT bracket until your income hits about $500k (or $300k if married filing separately)

So if you are in a low income period of your life, then yes it would be good to "tax gain harvest" up to the $47k total (other income plus capital gains), otherwise it would generally be better to limit capital gains and defer higher gains until your income is lower.

California's state capital gains tax rules (which I am unfamiliar with) would apply on top of that.