Orr's Island is connected to Great Island by the Orr's Island/Great Island Bridge, and is connected to the town of Brunswick on the mainland by Route 24 north over the Gurnet Bridge. Bowdoin College operates a 118-acre (48 ha) coastal studies center on Orr's Island.
As of 2000, Orr's Island had an estimated population of 752 people. 49.2% of the population were male, and 50.8% of the population was female. 98.1% of the population were white, 1.1% were Asian, 0.5% were two or more races, and 0.3% were some other race. Additionally, 83.9% of the population was 18 years or older, 23% were 65 years or older, and 4.3% were under 5 years of age.