The Magalloway River is a river in northwestern Maine and northern New Hampshire in the United States. It is a tributary of the Androscoggin River, which flows to the Kennebec River at Merrymeeting Bay in Maine, near the Atlantic Ocean. The total length of the river is 30 miles (48 km), or 48 miles (77 km) if the distances across intervening lakes are included.

The Androscoggin River is a river in the U.S. states of Maine and New Hampshire, in northern New England. It is 178 miles (286 km) long and joins the Kennebec River at Merrymeeting Bay in Maine before its water empties into the Gulf of Maine on the Atlantic Ocean. Its drainage basin is 3,530 square miles (9,100 km2) in area. The name "Androscoggin" comes from the Eastern Abenaki term Ammoscocongon, which referred to the entire portion of the river north of the Great Falls in Lewiston, Maine. The Anglicization of the Abenaki term is likely an analogical contamination with the colonial governor Edmund Andros.