SAN FRANCISCO--As expected, the San Francisco Board of Supervisors today approved a payroll tax cap for some businesses willing to move to the city's Mid-Market neighborhood.

The legislation and subsequent amendments passed by a vote of 8 to 3.

The Board in a preliminary vote agreed to grant the tax breaks last week by the same margin, 8 to 3. Mayor Ed Lee has said he will sign the measure.

The legislation's passing should come as good news to growing businesses in the city, but the poster child for this effort has been Twitter. The company currently resides in a building in the South of Market neighborhood and has been considering a move out of the city due to San Francisco's high payroll taxes and rents. Other tech firms like social-gaming company Zynga and Yelp, all born in San Francisco, have also threatened to leave the city for similar reasons.

The legislation that officially passed today will cap payroll taxes for companies with a payroll of at least $1 million for the next seven years. That cap would remain even if the companies add to their ranks. Additionally, employee income from exercising stock options will not be taxed.

Critics have said the legislation will drive away residents from one of the few neighborhoods in San Francisco with affordable rents and will deprive the city of a valuable source of revenue.

But those in favor say it will revitalize an economically depressed neighborhood and encourage successful businesses to remain in a city whose tax structure has been increasingly unfriendly to businesses.

CNET's Kent German contributed to this report.