San Francisco is 3 hours behind Boston. When it's 12:00 PM in Boston, it's 9:00 AM in San Francisco. Both cities observe DST, maintaining the 3-hour difference year-round.
Boston uses ET (Eastern Time) while San Francisco uses PT (Pacific Time).
Optimal window: 11:00 AM - 6:00 PM Boston time (8:00 AM - 3:00 PM San Francisco). Late morning calls from Boston catch business hours in SF.
Boston and San Francisco are both major biotech and tech hubs with extensive business partnerships.