Exercise & Assignment
Exercise is using your option to buy or sell the stock. Assignment is the seller being called on to fulfill it. Learn how the two sides connect and what triggers them.
Exercise is when an option buyer uses their right to buy or sell the stock at the strike. Assignment is the flip side: the seller of that option being called on to fulfill their obligation. They are two ends of the same event, one buyer exercising, one seller assigned.
These two words sound intimidating, but the idea is simple: someone cashes in their option, and someone on the other side has to deliver. Let me connect the two.
Cashing In the Coupon
Go back to the coupon idea. You hold a coupon for a discounted item. Exercising it means walking up to the counter and actually using it, claiming the discount. You had the right, and now you use it.
But every coupon the store honors costs the store something. When you exercise, the store is assigned: it must hand over the item at the discounted price it promised. Your action forces their obligation.
Options work the same way. When a buyer exercises, a seller somewhere is assigned and must complete the deal. One person's right becomes another person's duty.
What Happens on Each Side
Let us make it concrete with a call.
The buyer exercises a call. They use their right to buy 100 shares at the strike. If they hold a $200 call and the stock is at $220, exercising lets them buy at $200 and immediately own shares worth $220. They claimed the discount.
The call seller is assigned. They must deliver 100 shares at $200, even though the market is $220. If they own the shares (a covered call), they simply hand them over. If they do not (a naked call), they must buy at $220 to deliver at $200, a painful loss.
Puts work the same way in reverse. A put buyer exercising sells shares at the strike; the assigned put seller must buy them.
What You Actually Need to Know
Here is the reassuring part for a beginner. Most traders never exercise at all. They simply sell the option before expiration to collect its value, which is easier and avoids the paperwork of buying or selling 100 shares.
Exercise mostly matters at expiration: an in-the-money option is usually exercised automatically by your broker, and an out-of-the-money one just expires. And assignment is the risk to respect when you are a seller, because it can happen any time your sold option is in the money, occasionally even early. Know which side you are on: buyers control exercise, sellers absorb assignment.
- Exercise is the buyer using their right to buy or sell at the strike.
- Assignment is the seller being called on to fulfill it.
- They are two sides of one event: one buyer acts, one seller responds.
- Most traders sell to close instead of exercising; assignment is the seller's risk.
Pop Quiz
Three quick questions to see what stuck. Pick an answer and the explanation shows up right away.
What does it mean to exercise an option?
Exercising means actually using the option, buying or selling the stock at the strike, like cashing in a coupon.
Who gets assigned?
When a buyer exercises, a seller is assigned and must deliver the other side of the trade.
What do most traders do instead of exercising?
Selling to close is simpler than buying or selling 100 shares, so most traders take their value that way.
Bottom Line
Exercise and assignment are the two ends of one action: a buyer uses their option, and a seller has to deliver. Exercising a call buys shares at the strike; being assigned on it means delivering them. Puts run the same way in reverse.
In practice, most traders just sell their options to close. The word to respect as a seller is assignment, because it lands on you whenever your sold option is in the money.
Keep going: assignment before the deadline is early exercise, and it is the key risk in the covered call.