There is no shuttle to the Portland Jetport. The city of Portland took it away. You can either grab a taxi outside (there is a taxi stand, no need to call for one) or walk 5 minutes out to Congress St to take the #5 bus outbound to the Jetport.
Is there a shuttle from the airport to the bus station in Portland?
No
Yes. There's an express line to Boston Logan from Portland. Multiple runs per day.
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