Mammoth, Pennsylvania Demographics & Population 2026

A note before these figures: with a population of 373, Mammoth'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

Mammoth is a small community located in Pennsylvania, within Westmoreland County. The total population is 373. It ranks as the 1495th most populous out of 1,991 Census-designated places in Pennsylvania.

Age Demographics

The median age in Mammoth is 66.4 years. This is 62% higher than the state median of 40.9 years. Only 9.7% of residents are under 18, indicating fewer families with children. 20.4% 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 Mammoth is $39,219. This is 50% lower than the state median of $77,971. It is also 51% lower than the national median of $80,734. The poverty rate stands at 18.2%. This is 56% higher than the state poverty rate of 11.7%. The survey records no unemployed residents in Mammoth, which reflects the size of the sample rather than a labor market without joblessness. The median home value is $155,500. Housing costs are 39% lower than the state median of $254,500. The home-value-to-income ratio is 4.0x. 82.1% of occupied housing units are owner-occupied. This homeownership rate is 18% higher than the state average of 69.3%.

Race & Ethnicity

Every resident counted in Mammoth 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

5.9% of residents aged 25 and older hold a bachelor's degree or higher. This is among the lowest rates in the state, which may correlate with employment and income patterns. This is 83% lower than the state rate of 35.2%. Nationally, 35.7% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 79.2%.

Data Sources & Methodology

All demographic data for Mammoth, Pennsylvania 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 Pennsylvania state averages and national averages calculated from the same dataset. Rankings reflect the city's position among all 1,991 Census-designated places in Pennsylvania. Read more about how these figures are produced on our methodology page, or visit data.census.gov for official data.