Check Illinois gas prices today for regular, mid-grade, premium, and diesel fuel. The price tool below shows AAA-sourced daily averages, recent price movement, and a fill-up cost estimate for drivers across the Prairie State.
What Affects Illinois Gas Prices?
- High commuter and commercial demand in the Chicago metro area
- Heavy freight and trucking traffic along major interstate corridors like I-55, I-80, and I-90
- Illinois state motor fuel tax, which is among the highest in the nation
- Strict environmental boutique fuel blend requirements in the Chicago and East St. Louis regions
- Proximity to Midwest refineries and regional pipeline supply networks
- Delivery distances to rural farming communities in central and southern Illinois
Illinois Gas Prices by Fuel Type
- Regular: Most common fuel for everyday cars and daily commuters.
- Mid-grade: Used by vehicles that recommend slightly higher octane or for towing campers.
- Premium: Required by some performance, luxury, or turbocharged engines.
- Diesel: Important for trucks, RVs, commercial vehicles, and heavy-duty pickups moving freight across the state.
Illinois Gas Prices vs Nearby States
Regional borders in the Midwest create noticeable price shifts. When planning cross-state trips, keep these comparisons in mind:
- Indiana gas prices and Wisconsin gas prices often differ due to varying state taxes and local supply chain dynamics.
- Iowa gas prices and Missouri gas prices fluctuate based on their respective pipeline access, refinery conditions, and regional demand.
- Kentucky gas prices may be lower or higher depending on local market conditions and daily supply routes.
Tips for Getting Better Gas Prices in Illinois
- Compare station prices in Chicago or Springfield before heading onto rural stretches of I-55 or I-72.
- Fill up your tank before driving through remote agricultural areas in central or southern Illinois.
- Check your tire pressure regularly, especially during extreme Midwest winter cold and summer heat.
- Stick to regular unleaded unless your vehicle’s manufacturer explicitly requires premium.
- Plan your diesel and fuel stops along major freight corridors before long commercial hauls.
- Avoid unnecessary idling in heavy Chicagoland traffic or at busy tollway plazas.
Illinois Gas Price FAQs
What is the average gas price in Illinois today?
The current daily averages for regular, mid-grade, premium, and diesel are displayed in the dynamic tool at the top of this page.
Why do Chicago and downstate Illinois gas prices differ?
Chicago faces higher real estate costs, massive commuter demand, and strict boutique fuel mandates. Downstate areas like Springfield or Peoria have lower operating costs but may pay more for fuel delivery over longer distances.
Does Illinois use special gasoline blends?
Yes, the Chicago metro area and the East St. Louis region require specific reformulated gasoline (RFG) blends during the summer to reduce smog and meet federal air quality standards.
Is diesel included in Illinois gas price data?
Yes, the tool tracks Illinois diesel prices alongside unleaded options, which is essential for commercial truckers, agricultural transport, and RV travelers navigating the state’s major freight corridors.
Why are Illinois gas prices often higher than neighboring states?
Illinois has one of the highest state motor fuel taxes in the country, combined with specific environmental fuel mandates in major metro areas, which pushes retail prices above the national and regional averages.