S&P 500 ETF (SPY) Bitcoin Correlation

S&P 500 ETF (SPY) closed at $779 with a correlation to bitcoin of 0.37, which is weak positive correlation. That figure is measured on 90 days of daily returns as of Oct 10, 2026, and it moves as the window rolls forward. Its beta to bitcoin over the same window is 0.13, which is how far it moved per unit of bitcoin's move.

The S&P 500 ETF is the benchmark in this set rather than a bitcoin company. It is here as the control: whatever correlation it shows to bitcoin is the share attributable to the broad market rather than to anything crypto-specific.

Correlation measures whether two prices moved together, not whether one caused the other and not by how much. A company can hold bitcoin and still track it loosely, and a company that holds none can track it closely because both respond to the same conditions.

Beta is the other half of that question. It measures how far this asset moved per unit of bitcoin's move over the same window, so a beta above 1 describes an asset that has swung wider than bitcoin and one below 1 describes an asset that has swung less. It is an average over the window, not a rate the next move has to follow.