Day order vs good-till-canceled (GTC) order

A stock trades at $82. On Monday you place a buy limit for 10 shares at $78. As a day order, it ends at Monday's 4:00 PM close if the price never reaches $78, and you would need to place it again on Tuesday.

As a GTC order, it keeps waiting. If the stock dips to $78 on Thursday, the order fills and you pay $780. The risk is forgetting it: weeks later, a drop to $78 on bad news could fill an order you no longer want.

On JagSim the order ticket's Time in force has Day and Good til canceled. A Day order ends at the next close of the regular session, 4:00 PM New York time (1:00 PM on a half day), if it has not filled, even when it may fill before the open or after the close. A Good til canceled order has no end date: it waits under Open orders until it fills or you cancel it. Limit and stop orders for coins are always good til canceled, because coins trade at all hours. You can have up to 60 open orders at a time. How trading works on JagSim.

What does time in force mean?

The instruction that says how long an order stays open. Day and good-till-canceled are the most common; others include immediate-or-cancel and fill-or-kill.

Does a GTC order last forever?

At most brokers, no: many cancel a GTC order after a set number of days, which differs by broker. On JagSim a Good til canceled order has no end date, though it ends if the stock has no price or there is not enough cash or shares when it fills.

Which is better, a day order or a GTC order?

Neither. A day order suits a price that matters only today. A GTC order suits a level you would act on any day, as long as you check your open orders.

Does a day order work before the open or after the close?

It depends on the broker. On JagSim, a Day limit order with the extended-hours box ticked can fill before the open and after the close, and still ends at the next regular close.