The ride-sharing company had been threatened with legal action from regulators who said it did not have permission for the tests.
Initially, Uber said it would continue regardless but then decided to stop the trials a week after they had begun.
If granted, the $150 (Â£120) permit would allow the firm to restart tests.
"We are taking steps to complete our application to apply for a DMV [Department of Motor Vehicles] testing permit," an Uber spokeswoman said in a statement.
"Uber remains 100% committed to California."
The permit application has yet to be filed but two manually driven modified cars are already on the road, according to the Reuters news agency.
While the self-driving vehicles were briefly available in San Francisco last year, they were occasionally offered to Uber passengers via the company's ride-hailing app.
A driver was present in the vehicles and able to intervene as a safety precaution, the company said at the time.
An engineer was also present in the passenger seat.
However, criticism was levelled at the company after a video emerged of one of its modified Volvos apparently going through a red light during the December tests.
At the time, regulators pointed out that more than 20 other companies, including Google and Ford, tested their self-driving vehicles with a permit.
Uber has also performed self-driving car tests in Pittsburgh, Pennsylvania - where no permit is required.
Uber is applying for a permit to test its self-driving vehicles in California, after it was forced to suspend such trials in December.