Monomoscoy Island, Massachusetts Demographics & Population 2026

A note before these figures: with a population of 141, Monomoscoy Island'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

Monomoscoy Island is a small community located in Massachusetts, within Barnstable County. The total population is 141. It ranks as the 246th most populous out of 248 Census-designated places in Massachusetts.

Age Demographics

The median age in Monomoscoy Island is 49.1 years. This is 23% higher than the state median of 40.0 years.

Economy, Income & Housing

The median household income in Monomoscoy Island is $155,341. This is 49% higher than the state median of $103,960. It is also 92% higher than the national median of $80,734. The ACS records no residents below the poverty line in Monomoscoy Island. In a community this small the estimate rests on very few survey responses, so it should be read as an absence of measurement rather than a measured absence of poverty. The survey records no unemployed residents in Monomoscoy Island, which reflects the size of the sample rather than a labor market without joblessness. The median home value is $1,125,000. Housing costs are 100% higher than the state median of $562,100. The home-value-to-income ratio of 7.2x suggests that housing affordability is a significant concern for many residents. 89.5% of occupied housing units are owner-occupied. This homeownership rate is 43% higher than the state average of 62.5%.

Race & Ethnicity

Every resident counted in Monomoscoy Island was recorded as White (non-Hispanic). A figure of exactly 100.0% reflects a survey sample too small to capture the community's full composition rather than a precise measurement.

Education

72.0% of residents aged 25 and older hold a bachelor's degree or higher. This places Monomoscoy Island in the top 10% of all cities in the state for educational attainment. This is 52% higher than the state rate of 47.3%. 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, 47.7% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All demographic data for Monomoscoy Island, Massachusetts 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 Massachusetts state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 248 Census-designated places in Massachusetts. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.