Updated April 5, 2026 — Prices updated regularly from EIA data
Route • 6 states
About Interstate 20
Stretching 1,535 miles from Kent County, TX to Florence, SC, I-20 cuts through the heart of the Deep South. Gas prices along I-20 are among the most affordable in the country, reflecting the South's lower fuel taxes and proximity to Gulf Coast refineries.
For a trip along Interstate 20, a vehicle averaging 25 MPG would use approximately 1 gallon per 25 miles. At current average prices along the route, budget approximately {perMileCost} cents per mile for fuel. Plan fill-ups in lower-price states whenever possible.
Yes — consistently. Highway-exit gas stations charge 10-25 cents more per gallon than stations just 1-2 miles off the interstate. Whenever possible, exit the highway and drive to a commercial area for competitively priced fuel.
Gas prices along Interstate 20 vary significantly by state due to different fuel tax rates. States like Texas (20 cents/gallon), Missouri (17 cents), and Oklahoma (20 cents) consistently offer the most affordable fuel. Pennsylvania (59 cents) and California (67 cents) are among the most expensive.
Fill your tank before entering high-price states along your Interstate 20 route. Use the GasBuddy app to see upcoming prices and plan fill-up stops at the cheapest available locations. Always fill up when you have a quarter tank remaining — running low limits your options.
Interstate 20 passes through several states on its route. Oil-producing states like Texas, Oklahoma, Louisiana, North Dakota, and Wyoming typically offer the cheapest gas along any interstate that traverses them.