The mayor added that people can still register ahead of time, but making an appointment will not be required.
"Just show up during normal operation Monday through Saturday 8 a.m. through 3 p.m. and you will get your test," Garcetti said. "Moving forward you can register your information while you're waiting in line, just bring your insurance information or your ID if you don't have insurance."
The announcement was delivered during a briefing on the city's response to the pandemic.
RELATED: More than 12,000 vaccine appointments in Los Angeles delayed because of weather
Garcetti says the city has conducted more COVID-19 tests than there are people in the city, with more than 4 million tests done so far.
He also announced that the city is launching a new initiative called Mobile Outreach for Vaccine Equity, or MOVE, to scale up mobile vaccinations across vulnerable areas of L.A. It will put 10 mobile vaccination teams in the field by the end of next month and deploy them to high-risk areas.
Garcetti earlier on Thursday announced more than 12,000 vaccination appointments in L.A. scheduled for Friday will be postponed because of weather-related shipment delays as winter storms hit other parts of the country.
The city said the delays only affect the super sites, while vaccinations for the city's mobile clinics will continue as scheduled.
City News Service contributed to this report.