SAN FRANCISCO—The San Francisco Board of Supervisors on Tuesday, April 5 approved a measure that requires businesses with at least 20 employees to provide six weeks of fully paid family leave. The law will go into effect in 2017 and the businesses will share the family leave costs with the state.

This makes San Francisco the first city in the nation to require fully paid family leave. Advocates of the law noted that it was needed, because too many families can’t afford to take time off when a newborn enters their lives or they adopt a child.

Supervisor Scott Weiner agreed when he told NBC Bay Area news, “We’re trying to balance the needs of businesses and of many families who are struggling to get by. Especially low-income and working class families right now literally having to choose, ‘Do I spend time bonding with my child or put food on the table?’ And that is a choice no one should have to make.”

Small business owners say that this will be added to the long list of city mandates, like paid sick leave and healthcare, that unfairly target small businesses and it will cut into their competitive edge.

Mark Dwight, President of San Francisco’s Small Business Commission opposed the measure saying that these increased costs, higher rents and higher taxes could deter small businesses from opening in the city. “We are in the most expensive place to do business, and that’s all we’ve got. The economies of scale are just not there,” said Dwight.

Federal law grants up to 12 weeks unpaid family leave, and California state law grants six weeks of partial paid leave, although there is a bill waiting to be signed by the governor that would increase the paid leave to 70 percent. Certain businesses are generous in their family leave to help retain their employees, like Microsoft, Facebook and Yahoo. In the U.S., though, only California, Rhode Island and New Jersey provide partial pay now, and New York approved a law that grants up to 12 weeks partial pay last month.