Iowa vs Missouri gas prices
Regular gas is $0.13 a gallon cheaper in Missouri — $1.99 on a 15-gallon fill-up. The two share a border, so that gap is worth knowing before you cross it.
Iowa
Missouri| Grade | IA | MO | Diff. | |
|---|---|---|---|---|
| Regular | $4.11 | $3.98 | $0.13MO | Missouri |
| Midgrade | $4.37 | $4.33 | $0.04MO | Missouri |
| Premium | $4.95 | $4.69 | $0.26MO | Missouri |
| Diesel | $6.12 | $5.97 | $0.16MO | Missouri |
Is cheaper gas worth the detour?
Use your tank and extra travel costs. Prices below are AAA state averages as of 2026-09-16; check the actual station prices before driving.
Extra distance and time include the return to your original route. Detour fuel uses the higher state price. Tire wear and maintenance are excluded. This estimates a price difference; it does not verify a station offer or route.
Where the $0.13 gap actually comes from
8% of it is tax. Iowa charges $0.01 more per gallon in federal and state taxes than Missouri. The remaining $0.12 is a real difference in what the fuel, refining and distribution cost — refinery proximity, pipeline access and state fuel-blend rules.
Fuel, refining, distribution and marginFederal and state taxes Pre-tax figures are estimates — see the note below.
What the gap is worth
Based on today’s $0.13 per-gallon difference, which moves week to week. Use the fuel cost calculator for your own mileage and vehicle.
Prices by metro area
State averages hide a lot. These are the cheapest metros AAA reports on each side.
Other comparisons
Frequently asked questions
Is gas cheaper in Iowa or Missouri?
Regular gas is cheaper in Missouri, at $3.98 a gallon against $4.11 in Iowa — a gap of $0.13, or 3.2%. On a 15-gallon fill-up that is $1.99. Figures are AAA daily state averages for 2026-09-16.
Why is gas more expensive in Iowa?
8% of the $0.13 gap is tax rather than the cost of the fuel. Iowa levies $0.01 more per gallon in federal and state taxes; the remaining $0.12 is a genuine difference in what the fuel, refining and distribution cost.
Is diesel cheaper in Iowa or Missouri?
Diesel is cheaper in Missouri at $5.97 a gallon, against $6.12 in Iowa — $0.16 a gallon apart.
Is it worth crossing from Iowa into Missouri to fill up?
If you are already near the line, yes: a 15-gallon fill saves about $1.99. Driving out of your way for it rarely pays — at $4.11 a gallon and 25 mpg, a 6-mile round trip would eat the whole saving in fuel alone, before your time.
Why this price is what it is
- Premium vs. Regular Gas: Is Premium Actually Worth It?Premium costs more per gallon — but does it help your car? Here's when premium is worth it, when it's wasted money, and what octane really does.
- Fuel Taxes Explained: What You Really Pay Per GallonA big slice of every gallon is tax — but how much, and where does it go? A clear guide to federal, state and European fuel taxes.
- The Best Day and Time to Buy Gas (Backed by Price Data)Studies of billions of transactions point to early in the week as the cheapest time to fill up. Here's the best day, the best time of day, and why it works.