New Castle supports its own police force and elementary school. The town has a volunteer fire department, is affiliated with an EMT squad, and is a member of the area mutual aid pact. Policies New Castle's Comprehensive Plan does not provide for new industry or commercial activity. Residential and Commercial both require a minimum 20,000 square-foot lot size with 100 feet minimum frontage. Oceanside Beach requires one acre.
Future development permits a variety of uses on land largely undeveloped or in resort use.
Housing Shaded colonials, capes and contemporary-style homes dominate the area, enhanced by velvet lawns that carpet beautiful front and back yards. The center of this tiny community is filled with close neighbors residing in perfect examples of classical architecture, with approximately 90 houses showing evidence of construction dating back 250 years and more. Both approaches to the island feature newer homes, primarily contemporary structures of natural beauty secluded by tall pines and birches. Carefully controlled growth reflects New Castle's serious commitment to maintaining its special New England ambiance. Education New Castle residents are educated in the town's elementary school through the sixth grade.