Tesla has reinstated free use of its Supercharger stations for some recent buyers of Model S and Model X vehicles, in a partial reversal of a decision to limit free charging to 400 kilowatt hours annually (about 1,000 miles worth of driving) for Tesla vehicles sold after Jan. 15 .
The shift impacts anyone who bought a Model S or Model X between January 15th, when free Supercharging officially ended, and Friday, May 19th. Those buyers will be upgraded to free Supercharging retroactively.
Free Supercharging will also be available to future Model S or Model X buyers if they have a referral code from an existing Tesla owner. Each Tesla buyer can pass on five referral codes, which also come with a $1,000 discount for the new buyer, and earn some perks for referrers when used. Pre-owned vehicles and Model 3 orders aren't eligible for the referral program.
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Finally, anyone who already owns a Model S or Model X will get free Supercharging when they buy a new Model S or Model X, without needing a referral code.
The free Supercharging perk is pretty generous. According to Tesla’s numbers, Supercharging beyond the recent 400kwh limit costs and average of nearly $0.15 per kwh. Therefore, a Tesla owner who drives as little as 15,000 miles using Supercharger stations to refuel would save about $840 annually.
This article has been updated with clarfying information from Tesla.