What are US Options trading rules?

1) The Order Type

There are two order types available for Options orders.

Opening a position: Limit order and Market order

Closing a position: Limit order and Market order

2) Time-in-Force (Order Duration)

You can only place an order with DAY enabled under “Time-in-Force”.

3) Trading Hours for Options

There are no extended hours trading for Options.

Before expiration:

On US trading days, you can trade Options during regular market hours.

On the day of expiration:

2 hours before the market closes, you cannot open a new position (buy to open). The system will also cancel any unmatched open orders.

However, you may still close off your current position before the market closes.

US trading hours https://www.webull.co.za/help/faq/1519-What-are-the-trading-hours-of-the-US-market