Petersham, Massachusetts Demographics & Population 2026

A note before these figures: with a population of 312, Petersham'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

Petersham is a small community located in Massachusetts, within Worcester County. The total population is 312. It ranks as the 243rd most populous out of 248 Census-designated places in Massachusetts.

Age Demographics

The median age in Petersham is 56.8 years. This is 42% higher than the state median of 40.0 years. Only 3.9% 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 Petersham is $107,813. This is 4% higher than the state median of $103,960. It is also 34% higher than the national median of $80,734. The poverty rate stands at 6.1%. This is 39% lower than the state poverty rate of 10.0%. The unemployment rate is 0.7%. This is 86% lower than the state rate of 5.1%. The median home value is $389,100. Housing costs are 31% lower than the state median of $562,100. The home-value-to-income ratio is 3.6x. 92.0% of occupied housing units are owner-occupied. This homeownership rate is 47% higher than the state average of 62.5%.

Race & Ethnicity

Petersham has a predominantly White (non-Hispanic) population, comprising 94.5% of all residents. Hispanic or Latino residents account for 1.3%. The Hispanic or Latino population (1.3%) is well below the state average of 13.3%.

Education

48.6% of residents aged 25 and older hold a bachelor's degree or higher. This is 3% higher than the state rate of 47.3%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 97.2%. Notably, 30.9% of adults hold a graduate or professional degree, indicating a highly educated workforce.

Data Sources & Methodology

All demographic data for Petersham, 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.