Adjacent counties

• Somerset County – north
• Waldo County – east
• Sagadahoc County – south
• Lincoln County – south
• Androscoggin County – southwest
• Franklin County – northwest

2000 census

As of the census^[12] of 2000, there were 117,114 people, 47,683 households, and 31,327 families living in the county. The population density was 135 people per square mile (52 people/km²). There were 56,364 housing units at an average density of 65 per square mile (25/km²). The racial makeup of the county was 97.45% White, 0.34% Black or African American, 0.40% Native American, 0.59% Asian, 0.02% Pacific Islander, 0.18% from other races, and 1.02% from two or more races. 0.73% of the population were Hispanic or Latino of any race. 20.6% were of English, 17.4% French, 13.4% French Canadian, 10.9% United States or American and 9.9% Irish ancestry. 92.5% spoke only English at home, while 5.48% spoke French.^[13]

There were 47,683 households, out of which 31.20% had children under the age of 18 living with them, 51.60% were married couples living together, 10.00% had a female householder with no husband present, and 34.30% were non-families. 27.60% of all households were made up of individuals, and 10.60% had someone living alone who was 65 years of age or older. The average household size was 2.38 and the average family size was 2.89.^[14]

In the county, the population was spread out, with 23.80% under the age of 18, 8.50% from 18 to 24, 28.60% from 25 to 44, 24.90% from 45 to 64, and 14.20% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 94.00 males. For every 100 females age 18 and over, there were 90.80 males.

The median income for a household in the county was $36,498, and the median income for a family was $43,814. Males had a median income of $32,279 versus $24,032 for females. The per capita income for the county was $18,520. About 8.50% of families and 11.10% of the population were below the poverty line, including 13.20% of those under age 18 and 10.20% of those age 65 or over.

2010 census

As of the 2010 United States Census, there were 122,151 people, 51,128 households, and 32,368 families living in the county.^[14] The population density was 140.8 inhabitants per square mile (54.4/km²). There were 60,972 housing units at an average density of 70.3 units per square mile (27.1 units/km²).^[15] The racial makeup of the county was % from other races, and % from two or more races. Those of Hispanic or Latino origin made up % of the population.^[14] In terms of ancestry, 24.2% were English, 17.0% were Irish, 8.3% were German, 7.7% were French Canadian, 5.7% were American, and 5.4% were Scottish.^[16]

The median income for a household in the county was $45,973 and the median income for a family was $56,853. Males had a median income of $42,176 versus $32,471 for females. The per capita income for the county was $24,656. About 7.8% of families and 12.5% of the population were below the poverty line, including 16.9% of those under age 18 and 9.6% of those age 65 or over.^[17]

Voter registration

Cities

• Augusta (county seat)
• Gardiner
• Hallowell
• Waterville

Towns

Unorganized territory

• Unity

Census-designated places

• Clinton
• Farmingdale
• Oakland
• Winthrop

Other unincorporated villages

• China Village
• East Vassalboro
• East Winthrop
• Libby Hill
• North Monmouth
• North Vassalboro
• South China