Demographics is the study of populations, and from a demographic perspective, Westchester County’s population is growing, aging and becoming more diverse – racially, ethnically and linguistically (languages spoken).

From 2010 to 2024, the county’s population increased by 6%, reaching more than 1 million residents. This growth outpaced New York State overall (3%) but remained slower than national growth (10%).

The largest locality in Westchester County is the City of Yonkers, with a population of approximately 211,000 in 2024. Other population centers include Mount Vernon (157,500), Greenburgh (94,000) and New Rochelle (85,500). The fastest-growing localities since 2010 were Sleepy Hollow (16%), Harrison (14%), and Ardsley (14%).

Westchester County has grown more diverse since 2010-14. The Hispanic population grew fastest, increasing by 25% from 2010-14 to 2020-24, followed by the Asian population (16%), while the White population declined by 11%. The African American population decreased slightly (1%) over the same period.

Among age groups, between 2010–14 and 2020–24, the number of residents age 60 to 84 increased by 26%, and the population age 85 and older increased by 12%. By comparison, growth among younger adults ages 20 to 39 was modest (5%), while populations ages 40 to 59 and under 20 declined by 4% and 5%, respectively.

Of those 65 and older in the county, 37% lived alone in 2020-24 representing more than 48,300 people in Westchester County.

In 2020-24, 11% of the population in Westchester County, or about 105,500 people, had a disability, slightly below both the state and national rates (13%).

More than a third of Westchester residents spoke a language other than English at home – 35% in 2020-24, up from 33% in 2010-14. This rate exceeds both the state and national rates.

In 2020-24, 26% of the Westchester County population was foreign-born, a one percentage point increase since 2010-14, This is higher than the state rate (23%) and far above the national rate (14%).