The S&P 1500, or S&P Composite 1500 Index, is a stock market index of US stocks published by S&P Global. It combines stocks in the S&P 500, S&P MidCap 400, and S&P SmallCap 600. This index covers approximately 90% of the market capitalization of U.S. stocks and is a broad measure of the U.S. equity market.

The index was launched on May 18, 1995, with a first value date of December 30, 1994.^{[citation needed]}

Standard & Poor's also provides the S&P 900 index (a combination of the S&P 500 index plus the S&P MidCap 400) and the S&P 1000 (the S&P MidCap 400 plus the S&P SmallCap 600 index).

Like many indexes, the headline quote for the "S&P 1500" is a price return index; however, there is also "total return" version of the index, which includes dividends, interest and distributions (when applicable). These versions differ in how dividends are accounted for. The price return version does not account for dividends; it only captures the changes in the prices of the index components.

The following criteria are used by S&P Dow Jones Indices to determine eligibility for inclusion. The company publishes its full methodology details on its website.

The index rebalances quarterly in March, June, September, and December.^{[citation needed]}