Trades are not placed on the days that markets are closed. You can still place orders in your Stockpile account and they will show as "Pending" until they can be processed the next day the market is open.
Money movement, like deposits or withdrawals to your bank account, could be delayed an extra day due to the holidays.
Stockpile is closed on the following stock market holidays:
2021 Holidays
Friday, Jan. 1 — New Year's Day
Monday, Jan. 18 — Martin Luther King Jr. Day
Monday, Feb. 15 — Presidents' Day
Monday, May 31 — Memorial Day
Monday, July 5 — Observance of July 4, Independence Day, which occurs on a Sunday
Monday, Sept. 6 — Labor Day
Thursday, Nov. 25 — Thanksgiving Day
Friday, Dec. 24 — Observance of Christmas Day, which occurs on a Saturday