The posted price for Illinois Basin crude oil climbed to $99.88 per barrel Thursday, a sharp increase from $60.02 per barrel recorded the day after the conflict involving Iran began.
Local crude pricing is set by CountryMark Refining and Logistics, based in Mount Vernon. The Illinois Basin price is calculated by subtracting $7 from the benchmark price of West Texas Intermediate crude oil.
At the pump, prices are also rising. Unleaded regular gasoline in the Fairfield area has reached approximately $4.79 per gallon.
Experts point to the ongoing conflict as a major factor driving the increase, citing disruptions in global oil markets—particularly instability in the Strait of Hormuz, a critical passage that carries roughly 20 percent of the world’s oil supply.
Since the conflict began in late February, gas prices nationwide have jumped by more than $1 per gallon, marking one of the most significant energy price shocks in recent years.
The spike is also being fueled by seasonal demand as travel increases ahead of summer, combined with ongoing supply pressures.