Loading...
The final day an option can be bought or sold before it expires. For PM-settled options: expiration day itself. For AM-settled options (SPX monthly): the day before expiration (Thursday).
⚡
Key takeawayKnow when your last chance to close is. For AM-settled SPX: you must close by Thursday's close. For everything else: you have until Friday's close. Missing the last trading day means auto-exercise or expiration.
💡 Why It Matters
Missing the last trading day means you can't exit — your option auto-exercises or expires. For AM-settled index options, the last trading day is the day BEFORE expiration, which catches many traders off guard.
⚙ How It Works
PM-settled (most options): last trading day = expiration day (Friday, typically 4:00 PM close). AM-settled (SPX monthly): last trading day = Thursday before expiration. After the last trading day, the option settles automatically.
📋 Example
SPX monthly expiring Friday. Your last chance to trade is Thursday at 4:00 PM. If you hold through Thursday close, your fate depends on Friday's opening rotation — you can't adjust.
⚠ Common Mistakes
Holding AM-settled positions past Thursday close, thinking you can still exit Friday. You can't. Friday is settlement day, not trading day, for AM-settled products.
❓ FAQ
What is Last Trading Day?
The final day an option can be bought or sold before it expires. For PM-settled options: expiration day itself. For AM-settled options (SPX monthly): the day before expiration (Thursday).
Why does Last Trading Day matter for premium sellers?
Know when your last chance to close is. For AM-settled SPX: you must close by Thursday's close. For everything else: you have until Friday's close. Missing the last trading day means auto-exercise or expiration.
How does Last Trading Day work?
PM-settled (most options): last trading day = expiration day (Friday, typically 4:00 PM close). AM-settled (SPX monthly): last trading day = Thursday before expiration. After the last trading day, the option settles automatically.
What are common mistakes with Last Trading Day?
Holding AM-settled positions past Thursday close, thinking you can still exit Friday. You can't. Friday is settlement day, not trading day, for AM-settled products.
Related Terms
60/40 Tax Treatment
The favorable tax split for Section 1256 contracts: 60% of gains are taxed at the long-term capital gains rate and 40% at the short-term rate, regardless of ...
Adjusted Option
An option whose terms have been modified due to a corporate action — stock split, special dividend, merger, or spinoff.
All-or-None Order
An order that must fill completely or not at all, but unlike FOK, it can wait in the book for a complete fill rather than canceling immediately.
American-Style Option
An option that can be exercised by its holder at any time from listing until expiration.
This is not financial advice. Read our full investment disclaimer.