The phase-out will begin following completion of a four-month environmental review. Larger stores would then have six months to get rid of the plastic bags, while smaller stores will be allowed 12 months to phase them out.
Under the new law, shops will be able to offer customers paperbags for 10 cents each.
Environmental activists, including former Seinfeld actress Julia Louis-Dreyfus, had argued that the millions of plastic bags used in the city were a major blight in landfills, waterways and the ocean.
San Francisco was the first major US city to ban plastic bags in2007, and similar laws have since been enacted in dozens of smaller cities, including the US capital, Washington.//DPA