The Missouri gas tax is 29.5 cents per gallon on gasoline and diesel, the rate that took effect July 1, 2025, at the end of a five-year phase-in under Senate Bill 262.1Missouri Senate. Senate Bill 262 Everyday drivers can get part of that back. Missouri lets you claim a refund of the 12.5-cent portion added by SB 262 on fuel used for on-road driving, but only if you kept your receipts and file Form 4923-H during a narrow window each summer.2Missouri Department of Revenue. Motor Fuel Senate Bill 262
What You Actually Pay Per Gallon
Missouri’s 29.5-cent rate is the permanent cap and applies equally to gasoline and diesel.3Missouri Department of Revenue. Rate Increase Motor Fuel Bulletin On top of that, the federal government charges an excise tax on every gallon sold anywhere in the country: 18.4 cents per gallon on gasoline and 24.4 cents on diesel.4Office of the Law Revision Counsel. 26 USC 4081 Imposition of Tax
Add them together and a Missouri driver pays about 47.9 cents per gallon in combined fuel tax on gasoline, or 53.9 cents on diesel, before any local sales tax. The federal share hasn’t changed since 1993.
Where the Money Goes
The Missouri Constitution locks fuel tax revenue into transportation. It can’t be moved into the general fund or spent on anything other than roads and bridges.5Missouri Revisor of Statutes. Missouri Constitution Article IV Section 30(a) – Apportionment of Motor Vehicle Fuel Tax After collection costs, roughly 70 percent goes to the State Road Fund for state highway work, 15 percent goes to counties, and 15 percent goes to cities, towns, and villages for local road and bridge needs.6Missouri Constitution. Missouri Constitution Article IV Section 30(b) – Source and Application of State Road Fund
Getting the SB 262 Increase Refunded
Missouri offers a refund of the 12.5-cent increase for on-road fuel purchases, but the state does not send it automatically. You have to file for it. The refund covers only the amount added by SB 262, not the original 17-cent base rate.
Who Qualifies
Your vehicle must have a gross weight of 26,000 pounds or less, and the fuel must have been used on public roads.2Missouri Department of Revenue. Motor Fuel Senate Bill 262 That covers most passenger cars, pickups, and light trucks. Fuel burned off-road goes through a different refund, described further down.
The Form and the Math
Use Form 4923-H, the Highway Use Motor Fuel Refund Claim for Rate Increases. Do not confuse it with Form 4923, which is for non-highway fuel. Each vehicle needs its own worksheet listing the VIN, the date of each fuel purchase, the seller’s name and address, and the exact gallons bought.7Missouri Department of Revenue. Form 4923-H – Highway Use Motor Fuel Refund Claim for Rate Increases
The math is simple: multiply total gallons purchased during the fiscal year by $0.125. Buy 800 gallons in a year, get $100 back. Keep the original invoices. You’re certifying the numbers under penalty.
When to File
The window is short. Claims must be postmarked on or after July 1 and no later than September 30 following the fiscal year you’re claiming. For fuel bought between July 1, 2025, and June 30, 2026, the claim has to be postmarked between July 1, 2026, and September 30, 2026. Miss the window and the claim is denied, with no carryover to a future year.7Missouri Department of Revenue. Form 4923-H – Highway Use Motor Fuel Refund Claim for Rate Increases
Mail the form and worksheets to the Missouri Department of Revenue’s Taxation Division at P.O. Box 800, Jefferson City. If you’re claiming for more than 10 vehicles, the department encourages using its electronic portal. A new application is required every fiscal year.
Refund for Off-Road Fuel Use
A separate refund exists for fuel used entirely off public roads, and it’s more generous: it returns the full 29.5-cent rate, not just the 12.5-cent increase. It applies to fuel used in farm equipment, lawn mowers, off-road construction machinery, generators, aircraft engines, heating, marine use, and similar purposes.8Missouri Department of Revenue. Form 4923 – Non-Highway Use Motor Fuel Refund Claim
This program uses Form 4923 (no “H”) and has a longer deadline: within one year of the purchase date, or by April 15 following the year of purchase, whichever comes later. Before your claim can be processed, you also need Form 4924, the Non-Highway Motor Fuel Tax Refund Application, on file with the department.
If You Drive an EV or Alternative Fuel Vehicle
Drivers who don’t buy taxed motor fuel, or buy much less of it, pay through a separate annual decal instead. Missouri requires owners of electric vehicles, plug-in hybrids, and vehicles running on propane or natural gas to purchase an alternative fuel decal each year. The fee climbed 20 percent of its 2021 base annually for five years and reached its full amount in 2026.9Missouri Revisor of Statutes. Missouri Revised Statutes 142.869 – Alternative Fuel Decal
For 2026, on passenger vehicles and vehicles weighing 18,000 pounds or less:
- Fully electric, propane, or natural gas: $150, plus a $9 processing fee
- Plug-in hybrid electric: $75, plus a $9 processing fee
Heavier vehicles pay more. A non-farm commercial vehicle over 36,000 pounds on alternative fuel owes $1,500 a year; the plug-in hybrid version pays $750. Vehicles with historic plates are exempt from both the motor fuel tax and the decal requirement.10Missouri Department of Revenue. Special Fuel Decals