Louisiana needs to transition from per-gallon gas taxes to per-mile user fees
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Policy Study

Louisiana needs to transition from per-gallon gas taxes to per-mile user fees

With a mid-level shift to electric vehicles, Louisiana could anticipate annual fuel tax revenue would be reduced by $250 million by 2040 and over $325 million by 2050.


Roads in Louisiana and across the nation are primarily funded by per-gallon fuel taxes. Unlike many other states in the eastern half of the United States, Louisiana has no actual toll roads. Three tolled bridges are the Highway 1 Bridge, the Avery Island Toll Bridge, and the Lake Pontchartrain Causeway.

Two current trends threaten the long-term viability of per-gallon fuel taxes. One is ongoing revisions of federal miles per gallon (mpg) requirements for new vehicles (both personal vehicles and commercial trucks). The other is the trend toward replacing petroleum-fueled vehicles with electric vehicles.

Both of these trends are being driven by federal policy: federal Corporate Average Fuel Economy (CAFE) requirements and an array of mandates and subsidies for electric vehicles. Auto and truck producers have nearly all announced plans to phase out petroleum-fueled vehicles and replace them with electric vehicles in the coming decades.

This policy study estimates plausible declines in Louisiana’s gasoline and diesel tax revenue over the next several decades. It next explains the growing interest, nationwide, in shifting from per-gallon taxes to per-mile charges (referred to as mileage-based user fees, or MBUFs).

While three states have begun phasing in mileage-based user fees (also referred to in some states as road user charges—RUCs), a growing number of states have run pilot projects in which volunteer car and truck drivers test simulated MBUF systems, and important lessons have been learned from those pilot projects. Louisiana is planning a pilot project as this study is being written.

Switching from gas taxes to mileage-based user fees would be a major change for Louisiana, and the politics of making such a large change need to be considered. This study explores those challenges and suggests ways of addressing them in Louisiana.

Full Study: Replacing Louisiana’s Motor Fuel Taxes