A Market-on-Close (MOC) order does not need to specify a price and is submitted to execute as close to the closing price as possible.
The trading hours for MOC orders are 09:30 - 16:00 (ET).
2.1 If an MOC order is placed before the pre-market trading hours begin, the order will be queued for submission until the market opens.
If an MOC order is placed during regular trading hours, the order will be directly submitted to the exchange.
If an MOC order is placed after the market closes, the order will be queued for submission until the market opens and will then be executed as close as possible to the closing price on the next trading day.
2.2 The execution of MOC orders depends on the exchange. Operations to place, edit, or cancel an MOC order may fail between 15:45 - 16:00 (ET) during the regular trading hours. To place, edit, or cancel an MOC order on the current trading day, we suggest that you submit the request before 15:45 (ET).
2.3 MOC orders do not specify a price and may fill at an unexpected price when market conditions change rapidly.
2.4 MOC orders are priced using the Current Price multiplied by the market order multiplier*, which we may adjust from time to time based on market conditions. Placing a MOC order will reduce your buying power, but once the order is filled or cancelled, the amount of buying power will be adjusted accordingly.
Market Order Multiplier: In cases where a market order is submitted, taking into account the fluctuation of stock prices, a certain percentage will be added on top of the current market price to avoid the risk of overbuying. This adjusted market price will then be used to determine the order amount, and the percentage added may be subject to change.