Option Greeks measure how an option's price responds to changes in the stock price (delta and gamma), time (theta), implied volatility (vega), and interest rates (rho).

Gamma, theta, and vega are largest for strikes near the Spire stock price and shrink for strikes far above or below it. Theta grows as expiration gets closer, while vega is larger for expirations further out. Call delta runs from 0 to 1 and put delta from -1 to 0, near 0.50 and -0.50 at the money, and roughly estimates the chance that an option finishes in the money.

Spire IV rank is 8, so implied volatility is near the bottom of its one-year range. Higher implied volatility raises option premiums and daily time decay (theta), and spreads delta and gamma across a wider range of strikes. Over the past year, 30-day implied volatility ranged from 13.9% to 168.9%. See the SR implied volatility history for a longer view.

Across all open Spire options on Nov 4, 2026, net gamma exposure was $477.99K and net delta exposure was $2.71M per 1% move in the stock. The SR gamma exposure chart shows where that gamma sits by strike.

Spire Inc. is the holding company for Spire Missouri, Spire Alabama, other gas utilities, and gas-related businesses, focused on growing organically, investing in infrastructure, and advancing through innovation.