Tesla has announced plans for non-Tesla owners to use the Supercharger network in the U.S. One involves a pay per use option and the other one is a paid membership that gives you a reduced rate at Supercharger stations.
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Tesla Supercharger Membership for non-Teslas might be an absolute steal
Tesla's Supercharger membership for non-Tesla vehicles is amazingly worth it for its price at just $0.99 a month in the United States.