In plain English
What Good till cancelled means
A GTC order does not expire at the end of the trading day in the way a day order does. It stays live across sessions until the trader cancels it, the order fills, or the venue’s rules force it to end. Different markets may define persistence slightly differently.
Why it matters
GTC is useful when a trader wants an order to remain available without resubmitting it every session. That convenience can also create stale orders if the trader forgets about them, so users need to know how a venue handles duration, session rollovers, and product expirations.
Example
A trader places a limit buy order for 10 lots at a chosen price and sets it GTC. If the market never trades there that day, the order can remain active the next session until it is either matched, canceled, or expired by exchange rule.
Quick answers
Common questions
Is GTC the same everywhere?+
No. The basic idea is consistent, but the details can differ by market and platform. Some venues impose maximum durations or automatic expiry tied to contract life or administrative rules.
Does GTC mean the order can never be canceled automatically?+
No. It can still be canceled by the trader, filled, or ended by venue-specific expiry rules.
Sources