看來不同的券商有不同的日期:
Fidelity 新年前有一個提示: for 2024,買、賣股票的最後一天是12/31, open or close a short-sale position and have the transaction reported for 2024 是 12/30;
For E*Trade,
Key dates:
Dec 27, 2024—Last day to buy or sell stocks, mutual funds, and ETFs for 2024.
Dec 27, 2024—Last day to open or close a short-sale position and have the transaction reported for 2024.