[twoodfin]

Not really. I can make a million trades or one to gain $X and pay the same capital gains tax.

A financial transaction tax makes me much worse off in the former case. It disincentivizes trading volume by raising transaction costs, which have been on a long-term trend downward as markets have adopted technology and brokers have engaged in cutthroat competition. I believe that trend has been positive for markets, investors, and the economy as a whole.

[rcme]

Only within one calendar year. In your original AAPL / MSFT example, you’d need to pay taxes at the end of the year on any gains from your AAPL sale assuming that’s as your only trading activity in the year.