"For furloughed employees, unless you are contacted by your manager about a start date, you will remain on furlough until further notice, at least for another week," Valerie Capers Workman, the company's in-house counsel, said in the email sent to employees and seen by Reuters.
On 24 March Tesla suspended production at its plant in Fremont, California.
The extension comes days after San Francisco County health officials, along with five other counties in the Bay Area, have said they would review "shelter-in-place" orders which are set to expire on Sunday.
The new orders will keep and extend the restrictions through May, with limited easing for a small number of low-risk activities.
The firm was not immediately available to a request for comment from a Reuter.
Last month the electric carmaker furloughed all non-essential workers and implemented salary cuts due to the coronavirus outbreak during a shutdown of its U.S. production facilities.