Retail diesel prices in Michigan reached $6.27 per gallon on September 15, leading a surge of all time highs across the US Midwest. Refining margins for the fuel rose above $111 per barrel, the highest level on record, while the product traded at roughly $220 per barrel, more than double the price of prompt crude futures. Retail pump prices exceeded $6 per gallon in 35 states, and 42 states have now set all time records for diesel prices in 2026.

Ukrainian drone strikes on Russian refineries drove a spot price rebound of 11 to 13 cents per gallon. Gross margins for refiners reached $115.80 per barrel above crude in New York and $124 per barrel in California, though these figures include renewable fuel costs of about $14 per barrel. National retail diesel prices may reach $6.40 per gallon if current market constraints persist.