Tesla drivers may enjoy a vast network of Supercharger stations across the US, but it’s coming at a cost: the price of charging. The automaker has quietly raised prices per kilowatt hour for using the fast-charging stations.

The average increase for pay-per-use customers ranges from roughly 20 to 40 percent, according to Electrek. In California, for example, the price went from 20 cents per kWh to 26 cents. In Oregon, the price doubled from 12 cents to 24 cents, and New York’s went up five cents to 24 cents per kWh. Owners of new Model S and Model X vehicles continue to have 400kWh of credit per year, while Model 3 drivers have no credits.

“Tesla is committed to ensuring that Supercharger will never be a profit center,” the company says on its Supercharger site, despite efforts to make them more city-friendly or even larger for anticipated demand. Yet with more than 1,100 Supercharging stations currently in North America, the expected delivery of vastly more Teslas in 2018 — if the Model 3 starts hitting production goals — will clearly weigh on the network.

For now, though, one of the perks of driving a Tesla is having access to what is still a large fast-charging network. It’s just getting more expensive now.