INFORMATION CENTER:  1-800-639-3317
HOURS OF OPERATION: SUN–FRI 4:30 AM –10:00 PM, SAT 5:00 AM – 8:00 PM [email protected]
 
Recommended by a local, who has used them often and says that they have always been happy with the cleanliness and service (and price).
Concord Coach has a bus directly to and from Logan Airport that stops at each terminal outside baggage claim. No reservations necessary. First come, first serve.
Note no service to/from Manchester Airport. 
Round trip fare Logan/Plymouth is $57, one-way is $31.
The printable schedule is here: here

Two buses a day go from Logan to Plymouth:

  • 6:45 AM arrives in Plymouth 10:45 AM
  • 5:40 PM arrives in Plymouth 8:30 PM

Two buses a day go from Plymouth to Logan:

  • 8:00 AM arrives at Logan 10:35 AM
  • 2:00 PM arrives at Logan 4:35 PM

NOTE: There are also frequent buses between Logan and Concord NH from crack-o-dawn to late at night. Concord is 45min. to 1 hour away.

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Lake Region Airport Shuttle
1-888-386-8181
24 hour shuttle service for both Logan Airport in Boston, MA and Manchester/Boston Airport in Manchester, NH:
Fees can be shared if others take same shuttle with you, which they can possibly arrange if they see more people going to the same place around the same time. They have a 10% discount that applies if a lot of people are using their service for ASD Convention, and 10% discount on return.
Fees to/from Logan: 1st 2 people in the shuttle: $286 combined ($143/each).2nd 2 people: $25 extra (311 = $103 each  if 3 people, $78 each if 4 people)3rd 2 people: $25 extra (336 total = $67 if 5 people, $56 if 6)
Fees to/from Manchester: 

1st 2 people in the shuttle: $198 combined ($99/each).
2nd 2 people: $25 extra (223 = $75 each  if 3 people, $56 each if 4 people)
3rd 2 people: $25 extra (248 total = $50 if 5 people, $42 if 6)