Monhegan Post Office » Non-Profit Return to Monhegan:Guide LodgingShoppingArtsNon-ProfitsBoatsFood & DrinkServices Go back to directory. Add to Address Book. Monhegan Post Office Monhegan Post Office Work Phone: 207-594-0609work Website: https://tools.usps.com/locations/home.htm?location=1373504 Categories: Non-Profit Updated 9 hours ago.