Castine, Maine Demographics & Population 2026

A note before these figures: with a population of 996, Castine's ACS estimates come from a small number of survey responses and carry wide margins of error. Individual percentages below — particularly rates that round to 0% or 100% — are approximations, not precise measurements. See data.census.gov for the published margins of error.

Population Overview

Castine is a small community located in Maine, within Hancock County. The total population is 996. It ranks as the 105th most populous out of 155 Census-designated places in Maine.

Age Demographics

The median age in Castine is 20.4 years. This is 54% lower than the state median of 44.8 years. Only 6.9% of residents are under 18, indicating fewer families with children. 10.6% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in Castine is $168,516. This is 125% higher than the state median of $74,733. It is also 109% higher than the national median of $80,734. The poverty rate stands at 0.7%. This is 93% lower than the state poverty rate of 10.8%. This exceptionally low poverty rate indicates strong economic prosperity across the community. The unemployment rate is 3.6%. This is 6% lower than the state rate of 3.8%. The median home value is $798,800. Housing costs are 169% higher than the state median of $296,600. The home-value-to-income ratio is 4.7x. 90.2% of occupied housing units are owner-occupied. This homeownership rate is 21% higher than the state average of 74.3%.

Race & Ethnicity

Castine has a predominantly White (non-Hispanic) population, comprising 85.4% of all residents. Hispanic or Latino residents account for 5.5%. The Black or African American population is significantly higher than the state average (4.0% vs 1.8%). The Hispanic or Latino population is significantly higher than the state average (5.5% vs 2.2%).

Education

88.1% of residents aged 25 and older hold a bachelor's degree or higher. This places Castine in the top 10% of all cities in the state for educational attainment. This is 143% higher than the state rate of 36.2%. Nationally, 35.7% of adults hold at least a bachelor's degree. No surveyed resident aged 25 or older reported leaving school before earning a high school diploma, though a rate of exactly 100% reflects the limits of a small sample. Notably, 57.7% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All demographic data for Castine, Maine is sourced from the U.S. Census Bureau's American Community Survey (ACS) 2020–2024 5-Year Estimates. The ACS collects data from approximately 3.5 million households annually and pools five years of responses so that even small communities can be measured, though the margin of error widens as the population falls. Comparisons are made against Maine state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 155 Census-designated places in Maine. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.