Adjacent counties

• Chittenden County - north
• Washington County - northeast
• Orange County - east
• Windsor County - southeast
• Rutland County - south
• Washington County, New York - southwest
• Essex County, New York - west

National protected area

• Green Mountain National Forest (part)

2000 census

According to the 2000 census,^[11] there were 35,974 people, 13,068 households and 9,108 families living in the county. The population density was 47 people per square mile (18 people/km²). There were 15,312 housing units at an average density of 20 units per square mile (7.7 units/km²). The racial makeup of the county was 96.86% White, 0.54% Black or African American, 0.26% Native American, 0.73% Asian, 0.03% Pacific Islander, 0.29% from other races, and 1.29% from two or more races. 1.10% of the population were Hispanic or Latino of any race. 15.5% were of English, 12.7% American, 12.0% French, 10.8% French Canadian, 10.8% Irish and 6.7% German ancestry. 96.0% spoke English, 1.8% French and 1.2% Spanish as their first language.

There were 13,068 households, of which 34.40% had children under the age of 18 living with them, 57.40% were married couples living together, 8.30% had a female householder with no husband present, and 30.30% were non-families. 23.40% of all households were made up of individuals, and 8.90% had someone living alone who was 65 years of age or older. The average household size was 2.55 and the average family size was 3.02.

Age distribution was 24.90% under the age of 18, 12.50% from 18 to 24, 26.90% from 25 to 44, 24.30% from 45 to 64, and 11.30% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 97.70 males. For every 100 females age 18 and over, there were 95.40 males.

The median household income was $43,142, and the median family income was $49,351. Males had a median income of $31,836 versus $24,416 for females. The per capita income for the county was $19,539. About 5.10% of families and 8.60% of the population were below the poverty line, including 9.10% of those under age 18 and 8.00% of those age 65 or over.

For historical populations since 1900, see Historical U.S. Census totals for Addison County, Vermont

2010 census

As of the 2010 United States Census, there were 36,821 people, 14,084 households, and 9,340 families living in the county.^[12] The population density was 48.0 inhabitants per square mile (18.5/km²). There were 16,760 housing units at an average density of 21.9 per square mile (8.5/km²).^[13] The racial makeup of the county was 95.3% white, 1.4% Asian, 0.8% black or African American, 0.2% American Indian, 0.5% from other races, and 1.7% from two or more races. Those of Hispanic or Latino origin made up 1.9% of the population.^[12] In terms of ancestry, 18.1% were English, 17.2% were Irish, 12.0% were German, 7.5% were American, 7.2% were French Canadian, 5.9% were Italian, and 5.3% were Scottish.^[14]

Of the 14,084 households, 29.5% had children under the age of 18 living with them, 53.3% were married couples living together, 8.6% had a female householder with no husband present, 33.7% were non-families, and 25.5% of all households were made up of individuals. The average household size was 2.41 and the average family size was 2.88. The median age was 41.3 years.^[12]

The median income for a household in the county was $55,800 and the median income for a family was $67,721. Males had a median income of $43,643 versus $34,486 for females. The per capita income for the county was $26,599. About 5.7% of families and 11.3% of the population were below the poverty line, including 11.4% of those under age 18 and 5.8% of those age 65 or over.^[15]

Air

The Middlebury State Airport serves private aviation for Addison County. Commercial airlines are available to the north at Burlington International Airport in Chittenden County, and to the south at Rutland Southern Vermont Regional Airport in Rutland County.

Public transportation

Public bus service in Addison County is operated by Tri-Valley Transit (formerly ACTR). There is extensive bus service around Middlebury with connections to Vergennes, New Haven and Bristol, seasonal service to Middlebury Snow Bowl, as well as commuter buses to Burlington and Rutland operated in conjunction with Green Mountain Transit and the Marble Valley Regional Transit District, respectively.^[18]

Although the majority of rides are provided through the Shuttle Bus System, ACTR also operates a Dial-A-Ride System. This system enhances ACTR's ability to provide comprehensive transportation alternatives for all Addison County residents.^[19]

The Dial-A-Ride System includes programs that focus on specialized populations including elders, persons with disabilities, low-income families and individuals, as well as the visually impaired. Those eligible for Medicaid, Reach Up, are aged 60+ or with a disability may be eligible for free transportation. Nearly 40 Volunteer Drivers work with ACTR to provide these rides. Additional information about ACTR's transportation services are available at www.actr-vt.org.^[20]

Amtrak's daily Ethan Allen Express train serves two stations in Addison County: Middlebury and Ferrisburgh–Vergennes. The train makes major stops in Burlington, Rutland, Albany, and New York City. Begun in July 2022, this is the first regular passenger rail route in the county since the Rutland Railroad discontinued service in 1953.^[21]

Vermont Translines, an intercity bus carrier and interline partner with Greyhound and Amtrak, serves Addison County from Middlebury and Vergennes as well.

Major highways

City

• Vergennes

Towns

Census-designated places

• Bristol
• East Middlebury
• Lincoln
• Middlebury
• New Haven
• South Lincoln

Other unincorporated communities

• Bread Loaf
• Chimney Point
• Satans Kingdom