Is there bus service from Paine field that connects to Whidbey Island?

Bus from Mukileo to Paine Field?

Yes

There is according to Google. There isn't any info posted at Paine Field, but when I googled "Is there bus service from Paine Field to Whidbey Island?" I got a few options back, but it would also depend on the time of day your flight comes in because any busses will take you to the Clinton/Mukilteo ferry and you'll ride as a walk on passenger, then pickup a bus on the other side. Look up https://www.wsdot.wa.gov/ferries/, and I would also contact Community Transit 800-562-1375 and Island Transit 360-678-7771 for bus schedule, ticket info, and assistance with trip planning:)