☆ Op-ed: the real cost of California’s mileage-tax “study”
AB 1421 is not a harmless technical exercise. It is an early-stage blueprint for a per-mile tax regime that could materially raise costs for California drivers, without any guarantee of better roads, or improved mobility. So says Los Altos Institution’s policy prodigy Athan Joshi in an Opportunity Now exclusive op-ed.
Last week, the California State Assembly advanced AB 1421, a bill marketed as a “study” of road-user charges. In reality, the measure directs state agencies to compile research and recommendations for a mileage-based fee: a per-mile charge that would tax Californians based on how far they drive, regardless of income, commute distance, or whether they have practical alternatives to driving. The bill also sets a clear timetable: a report to the Legislature is due no later than January 1, 2027.
Calling it “research” doesn’t change what it sets in motion. It’s just warming up the machinery to add a mileage-based tax on top of the existing gas tax. California has already been testing this concept. The California Department of Transportation (Caltrans) ran a Road Charge Collection Pilot from August 2024 through January 2025 to evaluate how a per-mile charge could function.
What this could mean for households?
Even modest per-mile rates add up quickly because driving mileage is not discretionary for many workers and families. Depending on the assumed annual mileage, a per-mile fee in the 6-9 cents range would translate into:
15,000 miles/year → $900–$1,350 per driver
For a two-car household, that becomes $1,800–$2,700 annually before factoring in the rest of the cost of vehicle ownership.
And those costs would land on top of an already heavy baseline. California’s state gasoline excise tax is among the highest in the nation (70.9 cents/gallon in 2025), which is exactly why there is a worry that a mileage fee would be additive rather than a true replacement in practice.
Core issue of excess spending remains unaddressed
It’s true that fuel excise revenues face long-term pressure as the vehicle fleet electrifies and at some point the state needs to think about a new funding model. But California’s central transportation challenge isn’t a shortage of tax mechanisms. It is the spending discipline and project delivery. Creating a new statewide charging system risks becoming the next “solution” that expands revenue while leaving performance unchanged.
AB 1421 is not a harmless technical exercise. It is an early-stage blueprint for a per-mile tax regime that could materially raise costs for California drivers, without any guarantee of better roads, or improved mobility.
Follow Opportunity Now on Twitter @svopportunity
We prize letters from our thoughtful readers. Typed on a Smith Corona. Written in longhand on fine stationery. Scribbled on a napkin. Hey, even composed on email. Feel free to send your comments to us at opportunitynowsv@gmail.com or (snail mail) 1590 Calaveras Ave., SJ, CA 95126. Remember to be thoughtful and polite. We will post letters on an irregular basis on the main Opp Now site.