Bustins Island is an island in eastern Casco Bay, Maine, United States. It is part of the town of Freeport, in Cumberland County. The island has approximately 117 summer cottages. It operates its own ferry, the Lilly B, which debarks from the South Freeport town wharf. Typically, the ferry operates from Memorial Day weekend through Columbus Day weekend.
Although physically located within Freeport, the Bustins Island Village Corporation is a self-governing entity.
The island is named for John Bustion.