California does not charge a mileage tax. Drivers still pay a per-gallon gasoline excise tax, currently 61.2 cents, and electric vehicle owners pay a flat annual fee at registration.1California Department of Tax and Fee Administration. Fuel Taxes A voluntary state pilot is testing whether a per-mile road charge could eventually replace the gas tax, with a final report due to the legislature by December 31, 2026 and the authorizing law set to expire on January 1, 2027 unless lawmakers extend it.2LegiScan. CA SB 339 2021-2022 Regular Session Chaptered
Why the State Is Testing a Per-Mile Charge
Highway maintenance in California is funded mostly by the gas tax. The state collected roughly $7.9 billion in gasoline taxes in the 2024–25 fiscal year, but revenue tied to fuel sales keeps slipping as cars get more efficient and EVs skip the pump entirely.3California Department of Tax and Fee Administration. Gasoline Tax Data Road wear doesn’t drop just because fuel use does, and that gap is what the road charge concept is designed to close.
The logic of a mileage fee is simple: pay for what you use. A driver covering 15,000 miles in an electric sedan would owe the same road charge as a driver covering 15,000 miles in a gas-powered truck. Whether that approach actually works at scale is what the current pilot is trying to find out.
What a Mileage Fee Would Cost
No permanent rate has been set. The official California Road Charge site uses hypothetical rates of 2, 3, and 4 cents per mile for illustration, and any real rate would be set by the legislature.4California Road Charge. California Road Charge At 3 cents per mile, a driver covering 12,000 miles a year would owe $360 before any credits.
The pilot under SB 339 splits participants into two rate groups:2LegiScan. CA SB 339 2021-2022 Regular Session Chaptered
- A flat rate group, where every vehicle pays the same per-mile fee regardless of fuel type or efficiency.
- An individualized rate group, where each vehicle’s fee equals the state per-gallon fuel tax divided by that vehicle’s EPA fuel economy rating. At 61.2 cents per gallon, a car rated at 30 MPG would owe about 2.04 cents per mile; a car rated at 25 MPG would owe about 2.45 cents per mile.
Credits So You Don’t Pay Twice
The pilot is designed to be revenue-neutral for participants during testing. If you’re still buying gasoline, you’re already paying the state excise tax at the pump, and SB 339 requires participants to receive credits for state fuel taxes and EV registration fees already paid.2LegiScan. CA SB 339 2021-2022 Regular Session Chaptered
For a gas-powered car, the program estimates fuel used from your reported mileage and the EPA fuel economy rating, then credits the corresponding state tax. Drive 1,000 miles in a 25 MPG car and the system treats you as having burned 40 gallons, crediting about $24.48 in gas tax (40 × $0.612) against your road charge. You pay the net difference, if any.
For an EV, the $121 annual Road Improvement Fee gets prorated and credited the same way. The pilot is measuring how collection works, not shifting how much any individual owes.
What EV Owners Pay Right Now
California already charges a separate fee to electric vehicle owners to partly offset lost gas tax revenue. Under Vehicle Code Section 9250.6, the Road Improvement Fee applies to zero-emission vehicles of model year 2020 and later, currently set at $121 per year. It isn’t assessed on the initial registration of a new ZEV purchased from a licensed dealer, but it kicks in at renewal.5California DMV. Registration Fees
The fee is flat. An EV owner driving 5,000 miles a year pays the same $121 as one driving 25,000 miles. Replacing both this fee and the gas tax with a single per-mile charge is one of the outcomes the state is studying.
How Mileage Would Be Reported
Pilot participants can choose from several reporting methods, from low-tech to automated:4California Road Charge. California Road Charge
- An odometer photo submitted at set intervals. No hardware, no location data.
- A plug-in device without GPS that counts total miles but doesn’t track where you drove.
- A plug-in device with GPS that distinguishes miles on public roads from miles on private property, useful if you drive on agricultural land or private roads where a road charge wouldn’t apply.
- Connected vehicle technology that transmits mileage data through the car’s own systems, with no additional device needed.
Privacy
Vehicle Code Section 3090 requires the pilot’s advisory committee to consider protection of personally identifiable information, the risk of re-identifying location data even when personal details are stripped out, and the security of each reporting method.6California Legislative Information. California Vehicle Code VEH 3090 The non-GPS options exist for drivers who want to participate without the state seeing where they go.
Can the State Make You Pay One Today?
No. Participation in the road charge pilot is voluntary for non-government vehicles, and no statute currently authorizes California to assess a per-mile tax on the general driving public. What you owe today is the gas tax at the pump and, if you drive a qualifying EV, the $121 annual Road Improvement Fee at renewal.
What Happens After 2026
The California Transportation Agency’s final report on the SB 339 revenue collection pilot is due to the legislature by December 31, 2026, and the program’s statutory authority expires on January 1, 2027.2LegiScan. CA SB 339 2021-2022 Regular Session Chaptered For anything to continue past that date, lawmakers would need to pass new legislation, whether to extend testing, expand the program, or move toward a statewide rollout.
No permanent rate has been set and the legislature has not committed to implementing one. The pilot is measuring whether billing millions of individual accounts for mileage can be done without the administrative cost swallowing the revenue. That answer, due with the 2026 report, is what will determine whether California’s road funding eventually shifts from the pump to the odometer.