Cheapest 100LL Avgas in Illinois
19 FBOs with 100LL pricing · Updated daily
The average 100LL price in Illinois is $8.06/gal. Below are all FBOs ranked from cheapest to most expensive.
Prices updated daily · Last updated July 29, 2026
| # | FBO | Airport | Jet-A | 100LL |
|---|---|---|---|---|
| 1 | Quincy AviationBest Price | KUIN | $6.95 | $6.75 |
| 2 | Midwest Aviation | KMWA | $6.76 | $6.95 |
| 3 | Flightline | KMDH | $5.53 | $6.97 |
| 4 | Kankakee Valley Airport Authority | KIKK | $7.16 | $7.13 |
| 5 | Flightstar | KCMI | $7.28 | $7.33 |
| 6 | Emery Air | KRFD | $7.63 | $7.55 |
| 7 | Synergy Flight Center | KBMI | $7.57 | $7.68 |
| 8 | Gaitros Aviation | KDEC | $6.79 | $7.79 |
| 9 | West Star Aviation, Inc. | KALN | $7.53 | $7.87 |
| 10 | Stellar Aviation of Springfield | KSPI | $7.99 | $8.18 |
| 11 | DuPage Flight Center | KDPA | $7.69 | $8.36 |
| 12 | Byerly Aviation | KPIA | $7.74 | $8.37 |
| 13 | Ascension FBO Network | KPWK | $9.19 | $8.39 |
| 14 | Atlantic Aviation | KMDW | $10.42 | $8.47 |
| 15 | Elliott Aviation | KMLI | $7.28 | $8.77 |
| 16 | Atlantic Aviation | KPWK | $9.82 | $8.94 |
| 17 | Signature Aviation | KMDW | $9.75 | $8.99 |
| 18 | Signature Aviation | KPWK | $9.33 | $9.05 |
| 19 | Signature Aviation | KORD | $9.98 | $9.58 |
100LL Avgas Market Analysis in Illinois
We track 100LL avgas at 19 FBOs across 16 airports in Illinois. The cheapest 100LL is $6.75/gal at Quincy Aviation (KUIN), and the highest is $9.58/gal — a $2.83/gal difference depending on where you stop. 9 FBOs are below the $8.06/gal state average. For a typical 50-gallon piston top-off, the cheapest stop saves roughly $65 versus the average.
100LL is the standard fuel for most piston-engine aircraft. Because avgas volumes are smaller than Jet-A, prices are especially sensitive to local supplier logistics and airport traffic. Self-serve pumps usually undercut full-service by a wide margin and are often available 24/7. Figures update daily from AirNav reports.