A new benefit for Seattle commuters takes effect this month.

It requires businesses with 20 or more employees to offer them a chance to make a monthly, pre-tax payroll deduction for transit or vanpool expenses. The aim is to encourage employees to use transit options rather than single-occupancy vehicles.

To be in compliance, employers instead may provide transit passes that are fully or partially subsidized, according to Seattle’s Office of Labor Standards.

For more information, visit https://www.seattle.gov/laborstandards or call 206-256-5297. Final rules for how the ordinance will work are here. They cover how to calculate an employer subsidy for a transit pass and how the city will enforce the ordinance.