The initiative lets drivers give their friends a referral code to get six months of free charging via Tesla's Supercharger network.
Musk said the move was aimed at reducing costs incurred by the scheme. "It's adding too much cost to the cars, especially Model 3," he said.
The premium electric auto manufacturer has made a number of cost-cutting moves of late, as it looks to boost margins and expand profitability. Late last month, the firm cut prices on its Model 3 car in China, while this week it discontinued the lowest-priced versions of the Model S sedan and Model X SUV.