California air board adopts gasoline rule amendments supporting E15 fuel use

SACRAMENTO — The California Air Resources Board (CARB) on Thursday adopted amendments to the state's gasoline regulations to support the availability and use of E15 fuel, a move the board said supports expanding consumer fuel choices.

E15 is a vehicle fuel that blends up to 15% ethanol, which CARB described as a low-carbon alternative fuel. Previous California rules allowed up to 10% ethanol, the current standard at stations, according to the board.

CARB said E15 is legal in 50 states and available in 36 states.

The board said Thursday's vote gives more certainty to fuel producers and providers interested in selling E15 in California. It said the rulemaking was prioritized at Governor Newsom's direction.

According to CARB, a detailed scientific evaluation of E15 found its impacts to be comparable to E10, with a potential for slight improvement in air quality. The evaluation determined that the primary health and environmental concerns associated with the gasoline blend come from the petroleum portion of the fuel, the board said.

E15 will continue to be authorized for sale at California gas stations, CARB said. State law requires dispensers to be clearly labeled, and the board said consumers should consult their owner's manual to determine whether the fuel is compatible with their vehicle.

CARB said the availability of E15 could help reduce gas prices, adding that fuel providers set the price of gasoline and decide which fuels to sell.

In October 2025, Governor Newsom signed Assembly Bill 30, which allowed E15 to be sold in California while CARB finalized the rules. This week the governor signed Senate Bill 795 (Archuleta), which is intended to accelerate the approval process for E15 dispenser components while maintaining public health protections, according to CARB.