SPX Options vs. SPY Options: Which Should I Trade?

Trading options on the S&P 500 is a popular way to make money on the index. There are several ways traders use this index, but two of the most popular are to trade options on SPX or SPY. One key difference between the two is that SPX options are based on the index, while SPY options are based on an exchange-traded fund (ETF) that tracks the index.

What's the Difference Between SPX and SPY Options?

Dividends

Dividends are not normally paid to options holders. However, SPY pays a dividend every quarter. This is vital because if you trade with in-the-money (ITM) call options, you can exercise them to collect the dividend. To do this, you need to exercise your options on SPY before the ex-dividend date or own shares and place a call (called a covered call option).

It is important to be alert when trading ITM calls because most calls are exercised for the dividend on expiration Friday. Therefore, if you own these options, you cannot afford to lose the dividend.

The ex-dividend day for SPY is the third Friday of March, June, September, and December. If that day doesn't fall on a business day, it is pushed to the next business day.

Trading Style

There are two different trading styles, European and American. European style options can only be exercised on the expiration date, while American options can be exercised any time before the expiry date.

SPY options are American-style and may be exercised at any time after the trader buys them (before they expire).

Expiration

SPX options that expire on the third Friday stop trading the day before the third Friday (the third Thursday). On the third Friday, the settlement price is determined by the opening prices of each of the index's stocks. This price is the closing price for the expiration cycle. SPY options cease trading at the close of business on expiration Friday.

Settlement

SPY options are settled in shares. When you exercise your options, you'll buy (or sell) shares of the ETF. Cash is used to settle SPX options, so if you exercise and are in the money, you'll receive cash in your brokerage account.

Value

An SPX option is also about 10 times the value of an SPY option. For example, on April 9, 2020, SPX closed at 2,789.82 points, and SPY closed at $278.20.

It's vital to grasp that one SPX option with the same strike price and expiration is approximately 10 times the value of one SPY option. Therefore, each SPX point was the same as $100.

For example, suppose SPX was at 2,660 points, and SPY traded near $266. One in-the-money SPX option gives its owner the right to buy $266,000 worth of the underlying asset ($100 x 2,660).

One SPY option gives its owner the right to buy $26,600 worth of ETF shares (10% of $266,000). 

Which Is Right For You?

The assets within SPX do not trade, so there are no shares available to buy or sell. The options are written so that traders can bet on the S&P 500's price movements. SPX functions as a theoretical index with a price calculated as if it were a true index.

This means it has exactly the number of shares of each of the 500 stocks. So, while the SPX itself may not trade, both futures contracts and options based on the index do. This is why SPX options are settled in cash.

The SPY options are settled in shares because shares are being traded on an exchange. Therefore, the options contracts are written so that you take possession of shares when you exercise your option.

Which options are best for you depends upon your strategy and goals. If you want to take possession of shares to hold or trade again, SPY might work best. If you'd rather trade for value and receive cash in your account, SPX is an excellent choice.

Trading SPY options does bring some additional risk. For example, on the Monday following expiration, you end up owning shares. You'll owe the price of those shares at the expiry time, not the price on Monday. So if the price for the shares moves lower on Monday, you're paying more than they are worth on that day. However, if the price moves higher, you pay less than the current market price.

The Bottom Line

The two key differences between SPY vs. SPX options are that they are either American or European style, and SPY options are on an ETF while SPX options are on the prices of the index itself. You should understand the difference this makes for exercising your options. Additionally, the difference in value (and settlement) makes how much capital you have to buy the options important.

If you have more capital to spare and don't require dividends, SPX might be a good choice. On the other hand, SPY might be a better choice if you're a bit short on funds and can use the dividends.

Frequently Asked Questions (FAQs)

The Balance does not provide tax, investment, or financial services or advice. The information is being presented without consideration of the investment objectives, risk tolerance, or financial circumstances of any specific investor and might not be suitable for all investors. Past performance is not indicative of future results. Investing involves risk, including the possible loss of principal.