U.S. option symbols include most pertinent information about the contract inside the symbol itself, making it easy to read and understand what the symbol means. The best way to understand is with an example.
Deciphering The Option Symbol
Option Symbol Example: AAPL251219C00150000
| Place in the Option Symbol | Value | Explanation |
AAPL251219C00150000 |
AAPL | The underlying stock, ETF, or index symbol |
AAPL251219C00150000 |
25 | The two-digit expiration year |
AAPL251219C00150000 |
12 | The two-digit expiration month |
AAPL251219C00150000 |
19 | The two-digit expiration day |
AAPL251219C00150000 |
C | Option type, call or put |
AAPL251219C00150000 |
00 | Right-aligned padding with 0s to extend the strike price to exactly 8 digits |
AAPL251219C00150000 |
150 | The strike price in dollars |
AAPL251219C00150000 |
00 | The strike price in cents |
AAPL251219C00150000 |
0 | A final trailing 0 as padding, added after the cents |
Each Option Symbol Component Explained
Underlying Symbol – AAPL251219C00150000
This is the stock, ETF, or index symbol and it indicates what is the underlying ticker for this option. The underlying ticker’s price is what will determine whether the option will expire in the money or worthless.
Expiration Date In YYMMDD Format – AAPL251219C00150000
This date tells you the expiration of the option. For 99% of U.S.-traded options they will expire after market close on the date of expiration. For some index options, such as SPX options (but not SPXW options), they will expire at market open. The option’s closing price on this day will determine the option’s final value and whether it will be exercised or expire worthless.
Option Type, Call or Put – AAPL251219C00150000
In the middle of the option, after the date but before the strike price, there will be a letter C or letter P to indicate whether the option is a call or a put. Remember, calls are options that increase in value when the stock goes up and allow you to buy stock at the strike price and puts are options that increase in value when the stock goes down, allowing you to sell the stock at the strike price.
Right-Aligned 8 Digit Strike Price, Front-Padded With 0s And With 3 Digits For The Cents – AAPL251219C00150000
The number after the C or P letter is an 8 digit number that represents the strike price. This is where almost all beginner option traders get confused. The number has 3 different parts and is right aligned. That means when you’re writing this number, it helps to start from left and then work right. Its counterintuitive, but that’s how option symbols work.
Three Digits For The Strike Price’s Cents – AAPL251219C00150000
In a ticker like AAPL that’s worth $150 at the time of writing, there won’t be contracts that have cents. However, in lower-priced stocks, say INTC, which is trading around $30, you’ll have options with a strike price of $32.50 for example. Take a look at this Intel $32.50 call for Jan. 17, 2025: INTC250117C00032500. The last 3 digits are 500. Even though the U.S. dollar has just two digits for cents, options symbols use an extra trailing 0 after the cents. This is is the #1 error that trips up most traders who are not used to writing or reading option symbols. In fact, if you arrived at this blog post after being referred by our customer support, chances are you are here because of this issue.
Up to 5 Digits For the Strike Price in Dollars – AAPL251219C00150000
After the three digits for the cents, add the strike price of the option in dollars. In the case of this $150 AAPL call, that’s going to be 150. This can be as many or as few digits as needed. For sub-$10 strikes it’ll be a single digit. For $10-99 two digits, and so on up to a maximum of 5 digits.
Front-Padded 0s To Generate an 8 Digit Number – AAPL251219C00150000
Finally, the number needs to be front-padded with 0s until an 8-digit number has been generated. This is why we say the option strike price is right-aligned, since extra zeros are added to the front of the number in order to generate an 8-digit number. When the strike price of the option in dollars is 3 digits (in this example, $150), then there will be two leading 00s. When the strike price is 4 digits (say $4000 in the case of SPX), then there will be a single leading 0. On a sub-$10 strike price, there will be four leading 0000s.
