St. Louis, MO to San Antonio, TX Moving Truck Gas Cost

Fuel cost by truck size

Based on 903 miles, a gas price of $3.925 and a diesel price of $6.127 a gallon. Towing a car on a trailer or dolly lowers fuel economy by about 15%.

Truck	MPG	Gallons	Fuel cost	Towing a car
Cargo van	16	56	$222	$261
10 to 12 ft truck	11	82	$322	$379
15 to 17 ft truck	9	100	$394	$463
20 to 22 ft truck	8	113	$443	$521
26 ft truck	7	129	$506	$596
26 ft truck (diesel)	8	113	$692	$814

The gap between the smallest and largest trucks on this route is about $285 in fuel alone, so it pays to rent only as much truck as you need.

Fuel prices at each end of the move

Where	Gas	Diesel	Price basis
St. Louis, MO	$4.145	$6.352	Midwest average
San Antonio, TX	$3.704	$5.903	Texas average

Gas runs about $0.44 a gallon cheaper around San Antonio, TX. Most one-way rentals are returned near San Antonio, so that’s the cheaper place to top the tank back up to the level you picked it up at.

Weekly retail averages from the U.S. Energy Information Administration for the week of October 19, 2026. Prices along the way will vary. EIA source

Planning the drive

A loaded box truck is slower than a car on hills and safest at moderate speeds, and most drivers find 450 miles a comfortable day. That makes St. Louis, MO to San Antonio, TX a 3-day drive, so budget for hotel nights and meals on top of fuel. The rental itself and any per-mile fees are charged separately from fuel.

Other moves

Going the other way? See San Antonio, TX to St. Louis, MO.

Moving truck gas cost from St. Louis, MO to San Antonio, TX