Little Sunapee Lake covers an area of 486 acres and has a maximum depth of 43 feet. The lake is part of the Lake Sunapee watershed. Water flows out of it through Goose Pond and Otter Pond before entering Lake Sunapee. The lake is also known as "Twin Lakes" because of a long, narrow peninsula called Colby Point that almost divides it into two parts. The lake is popular for boating, fishing, swimming, and scenic views. Bucklin Beach is a public recreation area at the east end of the lake.

Little Sunapee Lake is west of I-89 and west of Lake Sunapee. There is a boat launch on Little Sunapee Road on the east end of the lake and a canoe and kyack launch on the north side of the lake on NH-114.