The Time In Force setting regulates how long your order will remain active until it is executed or expires. You can specify that your order be good until market close ( DAY ) or good until cancelled ( GTC ). You can also specify that your order carry over into pre- and post-market trading using one of the plus options (DAY+ or GTC+).
If you specify the GTC setting, the order will carry over into the next "day's" session. GTC orders placed during the regular trading session Monday will be suspended at 4 p.m. ET and resumed on Tuesday at 9:30 a.m. ET. Only orders with a "Time In Force+" option will carry over from the regular session to the pre- and post-market session.

Note: Options cannot be traded in the pre- and post-market sessions.
In the following table, all actions are good until the order either executes or is cancelled.
DAY |
A buy or sell order which automatically expires if it is not executed during that day's regular market session. |
DAY+ |
A buy or sell order which remains in effect for that day's regular market session and post-market session only. |
GTC |
A buy or sell order which remains in effect until it is either executed or canceled. Good only during regular market sessions. |
GTC+ |
A buy or sell order which remains in effect until it is either executed or canceled. Good for regular markets sessions and pre- and post-market sessions. |