City parking meters began operating on Sundays between noon and 6 p.m. on Jan. 6, but until now parking enforcement officers have only issued warnings.
Full enforcement will begin this Sunday, Jan. 27th, however, according to the San Francisco Municipal Transportation Agency.
Drivers have the option of pre-paying before noon, and the payment will not be credited to the meter until noon when meters are in effect.
Customers can also pay by phone by dialing (866) 490-7275 or downloading the app at www.paybyphone.com.
Meters that have been paid by phone will still show expired but enforcement officers can tell payments were made by scanning with a handheld device.
All city parking meters will also now have at least four-hour time limits on Sundays, according to the SFMTA.
Parking meters in the Fisherman's Wharf area will continue to operate from 7 a.m. to 7 p.m. on Sundays, and in the Port of San Francisco's jurisdiction from 7 a.m. to 11 p.m.