St. Mary's County Demographics

A map of St. Mary's County's Population by Race

St. Mary's County, Maryland had a population of 113,777 in 2020. It was 70.5% White, 14.1% Black, 2.9% Asian, 5.8% Hispanic, 0.8% Native American/Other, and 5.9% Multiracial. This map presents the population of St. Mary's County, with one dot drawn for each person counted in the 2020 Census, color-coded by race.

St. Mary's County is the 12th most populous county of the 24 counties in Maryland.

St. Mary's County's White Population

80,233 residents of St. Mary's County identify as White, or 70.5%. This makes the White share of the population of St. Mary's County considerably larger than the White share of the population of Maryland (47.2% White). Of the 24 counties in Maryland, St. Mary's County is ranked #13 in terms of White residents as a share of the population.

St. Mary's County is more White than neighboring Westmoreland County (63.6% White), Richmond County (62.4% White), Northumberland County (70.2% White), and Dorchester County (61.1% White). St. Mary's County is less White than neighboring Calvert County (74.1% White).

St. Mary's County's Black Population

15,994 residents of St. Mary's County identify as Black, or 14.1%. This makes the Black share of the population of St. Mary's County less than the Black share of the population of Maryland (29.1% Black). Of the 24 counties in Maryland, St. Mary's County is ranked #13 in terms of Black residents as a share of the population.

St. Mary's County is more Black than neighboring Calvert County (12.8% Black). St. Mary's County is less Black than neighboring Westmoreland County (24.2% Black), Richmond County (27.1% Black), Northumberland County (22.6% Black), and Dorchester County (27.7% Black).

St. Mary's County's Asian Population

3,301 residents of St. Mary's County identify as Asian, or 2.9%. This makes the Asian share of the population of St. Mary's County roughly similar to the Asian share of the population of Maryland (6.8% Asian). Of the 24 counties in Maryland, St. Mary's County is ranked #11 in terms of Asian residents as a share of the population.

St. Mary's County is more Asian than neighboring Westmoreland County (0.8% Asian), Calvert County (1.7% Asian), Richmond County (0.5% Asian), Northumberland County (0.6% Asian), and Dorchester County (1.1% Asian).

St. Mary's County's Hispanic Population

6,545 residents of St. Mary's County identify as Hispanic, or 5.8%. This makes the Hispanic share of the population of St. Mary's County slightly less than the Hispanic share of the population of Maryland (11.8% Hispanic). Of the 24 counties in Maryland, St. Mary's County is ranked #13 in terms of Hispanic residents as a share of the population.

St. Mary's County is more Hispanic than neighboring Westmoreland County (5.7% Hispanic), Calvert County (4.5% Hispanic), Northumberland County (3% Hispanic), and Dorchester County (5.5% Hispanic). St. Mary's County is less Hispanic than neighboring Richmond County (6.7% Hispanic).

St. Mary's County's Native American/Other Population

937 residents of St. Mary's County identify as American Indian/Alaska Native/Native Hawaiian/Pacific Islander/Other, or 0.8%. This makes the Native American/Other share of the population of St. Mary's County roughly similar to the Native American/Other share of the population of Maryland (0.8% Native American/Other). Of the 24 counties in Maryland, St. Mary's County is ranked #5 in terms of Native American/Other residents as a share of the population.

St. Mary's County is more Native American/Other than neighboring Calvert County (0.7% Native American/Other), Richmond County (0.2% Native American/Other), Northumberland County (0.6% Native American/Other), and Dorchester County (0.7% Native American/Other).

St. Mary's County's Multiracial Population

6,767 residents of St. Mary's County identify as Multiracial, or 5.9%. This makes the Multiracial share of the population of St. Mary's County roughly similar to the Multiracial share of the population of Maryland (4.4% Multiracial). Of the 24 counties in Maryland, St. Mary's County is ranked #2 in terms of Multiracial residents as a share of the population.

St. Mary's County is more Multiracial than neighboring Westmoreland County (4.9% Multiracial), Richmond County (3.1% Multiracial), Northumberland County (3.1% Multiracial), and Dorchester County (3.9% Multiracial). St. Mary's County is less Multiracial than neighboring Calvert County (6.1% Multiracial).

Source: 2020 Census State Redistricting Data and Census TIGER/Line Shapefiles.