California Senate Bill 63 (SB 63), titled the Connect Bay Area Act, is a 2025 California bill signed into law that authorizes a five-county sales tax measure to be placed on the November 2026 ballot. If approved by voters, the measure would enact a 14-year tax projected to raise $980 million per year to fund the day-to-day operations of various San Francisco Bay Area transit agencies.
The act authorizes a 14-year sales tax, levying a half-cent tax in Alameda, Contra Costa, San Mateo, and Santa Clara counties, and a one-cent tax in San Francisco. In addition to funding, the bill requires operators receiving funds to adhere to the Metropolitan Transportation Commission (MTC)'s Regional Network Management policies. These policies are designed to improve coordination through measures such as free or discounted transfers, schedule alignment, unified wayfinding, and transit priority on streets. The bill also mandates that agencies undergo third-party financial efficiency reviews to identify potential cost savings and submit implementation plans to the MTC.
SB 63 was developed in response to structural deficits for Bay Area transit agencies facing depleted pandemic-era federal relief funds, including San Francisco, which is also considering a new parcel tax to fund Muni. The bill is a smaller successor to the 2024 Senate Bill 1031, a more ambitious nine-county plan to raise $1.5 billion annually that failed due to disputes over the tax type and how revenue would be allocated. It also follows a 2023 proposal by Senator Wiener to increase tolls on the region's bridges to fund transit.
Senator Scott Wiener introduced the bill in March 2025, along with co-author Senator Jesse Arreguin. It initially included only Contra Costa, Alameda and San Francisco counties.
The tax won't go to the ballot until either the transit agencies send it to voters (requiring a two-thirds approval) or a voter initiative path (requiring a simple majority).
The bill garnered support from transit advocates and local officials. The urbanist think-tank SPUR backed the bill on the grounds that "the need for new funding is dire" and the bill is "practical and politically realistic". MTC Chair and Pleasant Hill Mayor Sue Noack testified in Sacramento in support of the measure to prevent major service cuts. In July, San Francisco's 11 city supervisors voted to reaffirm their support. Caltrain said without the funding the impacts could include closing 1/3 of stations, no weekend service, only running once an hour, stopping at 9pm, and cutting service area.
In June, before the bill was signed, Bay Area Forward, an advocacy group of transit operators and unions, argued for switching to a gross receipts tax to shift the financial burden from individuals to businesses, a change that was opposed by the business association Bay Area Council.
San Mateo estimated that by 2031 the tax would bring in $135 million annually, $32.5 million of which would be used for Caltrain. Santa Clara expects to receive $264 million annually. The MTC expects the tax to generate $980 million annually across the five counties.
The law sets detailed fixed percentage allocations. The table below shows a summary of these percentages and estimated dollar amounts (assuming $980 million in annual revenue).