Trade vs Settlement date?

For end-of-the-year dividends, see your 1099-DIV.

For stocks, bonds and mutual funds you own, the taxable event is the trade date.

Dividends: For stocks that you own, the taxable event is the date of distribution or what the corporation refers to as the payable date. The ex-dividend date is set by the exchanges to two business days (cash dividend) before the company announced record date. Anyone buying the stock on or after the ex-dividend date will not get the next dividend distribution. The procedure for a stock dividend is slightly different, but the taxable event is still the payable date.

For mutual funds that you own, the taxable event is also the payable date for the dividend. However, unlike stocks, the dividend can be declared payable before year-end but not actually credited to your account until after year-end.

Although if you close at a loss what began as a sell-to-open you use settlement date.

Example: Buy back at a loss shares that you sold short, and use the settlement date for that purchase date.

I assume you are referring to short sales. It is my understanding that the taxable event (gain or loss) occurs on the day you deliver the asset. For securities, that would be the settlement date whether there is a gain or loss. There is an exception to this rule for worthless securities.

For information on how puts and calls (options) are handled, see: