What is the average cost of public transportation in Seattle?

Standard adult fare for buses and Link light rail trains are $2.50 during peak hours and $2.25 during off hours. On buses you get free transfers within a couple hours of boarding. That will get you anywhere within the King Co Metro system so it does not vary by route. You cannot transfer free between buses and trains, however. Also, Sounder trains are more expensive but travel further north and south.