State Street SPDR S&P 500 ETF Trust (SPY) Volume & Open Interest

Volume and open interest by strike show where trading activity and outstanding positions are concentrated. Clusters of OI often act as support and resistance levels.

Snapshot as of Apr 24, 2026.

Spot Price

$713.74

Total Volume

10.0M

Total OI

18.3M

Call OI

5.8M

Put OI

12.6M

Gamma Concentration

0.03

As of Apr 24, 2026, State Street SPDR S&P 500 ETF Trust (SPY) has 10.0M contracts traded today against 18.3M contracts outstanding. Open interest breaks down as 5.8M calls and 12.6M puts. Turnover ratio is 0.55 — high churn, indicating active repositioning. Gamma concentration is 0.03 — open interest is more distributed across strikes. Comparing today's volume to accumulated open interest reveals whether flow is opening new positions or closing existing ones, with heavy OI strikes often acting as support and resistance.