Tanking Tesla sales in California are slowing the state’s transition to all zero-emission vehicles.

The Texas-based electric-vehicle maker’s sales in the state fell 15% in the first quarter, according to the California New Car Dealers Association, which cited Experian data.

The sales decline for the U.S. EV market leader capped a year and a half of Tesla decreases in California, a leader in EV adoption. The carmaker’s market share stood at about 12% at the end of the quarter. Tesla nevertheless had the state’s best-selling passenger car in its Model 3.

The direct-sales automaker’s loss of favor in California is putting a drag on the state’s EV adoption efforts. Zero-emission vehicle sales there have fallen for two straight quarters to about 21% market share.

The state, which leads the country in EV registrations, according to Experian, has a mandate that all new-vehicle sales be zero-emission models by 2035. The CNCDA is trying to convince the California Air Resources Board to slow that timeline, saying automakers aren’t equipped to meet it.

"Dealers sell what customers want to buy,” said association Chairman Robb Hernandez, president of Camino Real Chevrolet. “No mandate can force consumers to choose otherwise. Although the manufacturers we represent are increasing EV sales in California, with the substantial decline in Tesla sales, EV market penetration is largely flat." 

Overall California new-vehicle sales rose in the quarter as consumers mirrored auto buying trends across the country spurred in large part by a rush to beat expected price inflation from U.S. trade tariffs. Year-over-year registrations increased 8% in the quarter, said CNCDA, which nevertheless forecasts a 2% annual sales slump due to the tariffs.

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