Time-in-Force & Order Conditions

Introduction

Besides price, orders have conditions that control how long they stay active and how they fill — known as time-in-force and flags. This lesson covers the common ones.

Time-in-Force

Time-in-force tells the exchange how long an order remains live:

• Day — valid only for the current trading session
• GTC (Good-Til-Cancelled) — stays active until filled or you cancel it
• IOC (Immediate-or-Cancel) — fills as much as possible now, cancels the rest
• FOK (Fill-or-Kill) — must fill entirely now or is cancelled

Day vs GTC

• A Day order expires at that day's close if unfilled
• A GTC order can persist for weeks until filled or cancelled (watch for stale prices)

IOC vs FOK

Both are for immediacy:

IOC: fill as much immediately, cancel the remainder
FOK: fill the whole order now, or cancel it entirely

Why Conditions Matter

Conditions give you control:

• Avoid accidentally buying at a stale price (Day/GTC limits)
• Cap risk by ensuring immediate or full fills (IOC/FOK)
• Manage orders you may forget about (GTC)

Practical Advice

• Default to Day or short time-in-force for active trading
• Use GTC only when you intentionally want a persistent limit
• Review open GTC orders regularly
• Use limit orders so conditions never expose you to surprise prices

Real-World Example

You set a GTC limit order to buy a stock at $40. Two weeks later the price dips to $40 and your order fills — even though you stopped watching. Understanding GTC helps you remember it's still live.

Summary

• Time-in-force controls how long an order stays active
• Day = current session; GTC = until filled/cancelled
• IOC fills what it can now; FOK requires a full immediate fill
• Conditions give control over fill timing and risk
• Review persistent orders and use limit prices

Next Lesson

How market data and news shape prices — and how to react sensibly.