According to the United States Census Bureau, the borough had a total area of 1.471 square miles (3.810 km2), including 1.452 square miles (3.761 km2) of land and 0.019 square miles (0.048 km2) of water (1.27%).
The 2010 United States Census counted 606 people, 241 households, and 163.9 families residing in the borough. The population density was 417.3 per square mile (161.1/km2). The borough contained 263 housing units at an average density of 181.1 per square mile (69.9/km2). The racial makeup of the borough was 91.75% (556) White, 1.16% (7) Black or African American, 0.33% (2) Native American, 2.15% (13) Asian, 0.00% (0) Pacific Islander, 2.64% (16) from other races, and 1.98% (12) from two or more races. Hispanics or Latinos of any race were 7.59% (46) of the population.
Out of a total of 241 households, 28.6% had children under the age of 18 living with them, 50.6% were married couples living together, 12.4% had a female householder with no husband present, and 32.0% were non-families. 22.8% of all households were made up of individuals, and 9.1% had someone living alone who was 65 years of age or older. The average household size was 2.51 and the average family size was 2.91.
In the borough, 21.1% of the population were under the age of 18, 7.6% from 18 to 24, 28.7% from 25 to 44, 30.5% from 45 to 64, and 12.0% who were 65 years of age or older. The median age was 40.4 years. For every 100 females the census counted 99.3 males, but for 100 females at least 18 years old, it was 100.8 males.
The Census Bureau's 2006-2010 American Community Survey showed that (in 2010 inflation-adjusted dollars) median household income was $67,000 (with a margin of error of +/- $20,882) and the median family income was $78,889 (+/- $19,386). Males had a median income of $54,583 (+/- $21,861) versus $41,667 (+/- $24,816) for females. The per capita income for the borough was $34,262 (+/- $7,656). About 6.7% of families and 12.7% of the population were below the poverty line, including 21.3% of those under age 18 and 0.0% of those age 65 or over.
As of the 2000 United States Census there were 658 people, 261 households, and 180 families residing in the borough. The population density was 451.9 people per square mile (174.0/km2). There were 273 housing units at an average density of 187.5 per square mile (72.2/km2). The racial makeup of the borough was 92.71% White, 2.28% African American, 0.76% Native American, 2.28% Asian, 0.15% Pacific Islander, 1.22% from other races, and 0.61% from two or more races. Hispanic or Latino of any race were 2.58% of the population.
There were 261 households out of which 29.1% had children under the age of 18 living with them, 50.6% were married couples living together, 14.2% had a female householder with no husband present, and 30.7% were non-families. 24.9% of all households were made up of individuals and 6.5% had someone living alone who was 65 years of age or older. The average household size was 2.52 and the average family size was 2.98.
In the borough the population was spread out with 21.7% under the age of 18, 7.6% from 18 to 24, 35.3% from 25 to 44, 25.5% from 45 to 64, and 9.9% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 103.7 males. For every 100 females age 18 and over, there were 98.8 males.
The median income for a household in the borough was $60,000, and the median income for a family was $69,688. Males had a median income of $38,056 versus $30,950 for females. The per capita income for the borough was $25,914. None of the families and 2.8% of the population were living below the poverty line, including no under eighteens and 9.1% of those over 64.
Andover is governed under the Borough form of New Jersey municipal government. The governing body consists of a Mayor and a Borough Council comprising six council members, with all positions elected at-large on a partisan basis as part of the November general election. A Mayor is elected directly by the voters to a four-year term of office. The Borough Council consists of six members elected to serve three-year terms on a staggered basis, with two seats coming up for election each year in a three-year cycle. The Borough form of government used by Andover, the most common system used in the state, is a "weak mayor / strong council" government in which council members act as the legislative body with the mayor presiding at meetings and voting only in the event of a tie. The mayor can veto ordinances subject to an override by a two-thirds majority vote of the council. The mayor makes committee and liaison assignments for council members, and most appointments are made by the mayor with the advice and consent of the council.
As of 2016, the Mayor of Andover Borough is Republican John A. Morgan, whose term of office ends December 31, 2019. Members of the Borough Council are Council President Michael Figueiredo (D, 2016; elected to serve an unexpired term), Lynn T. Delfing (R, 2017), Melvin Dennison (R, 2018), John Hoag (R, 2017; appointed to serve an unexpired term until November 2016 election), Peter Pearson (D, 2016) and Robert L. Smith (R, 2018).
In February 2016, the Borough Council chose John Hoag from three candidates proposed by the Republican municipal committee to fill the seat that had been held Eskil S. Danielson that will expire in December 2017; Hoag will serve on an interim basis until the November 2016 general election, when voters will choose someone to serve the balance of the term.
In February 2015, the Borogh Council selected Michael Figueiredo from a list of three candidates nominated by the Democratic municipal committee to fill the seat expiring in December 2016 that became vacant when Deborah McGowan resigned from office. Figueiredo served on an interim basis until the November 2015 general election, when he was elected to serve the one year remaining on the term of office.
Andover Borough is located in the 5th Congressional district and is part of New Jersey's 24th state legislative district.
New Jersey's Fifth Congressional District is represented by Josh Gottheimer (D, Wyckoff). New Jersey is represented in the United States Senate by Cory Booker (D, Newark, term ends 2021) and Bob Menendez (D, Paramus, 2019).
For the 2016–2017 session (Senate, General Assembly), the 24th Legislative District of the New Jersey Legislature is represented in the State Senate by Steve Oroho (R, Franklin) and in the General Assembly by Parker Space (R, Wantage Township) and Gail Phoebus (R, Andover Township). The Governor of New Jersey is Chris Christie (R, Mendham Township). The Lieutenant Governor of New Jersey is Kim Guadagno (R, Monmouth Beach).
Sussex County is governed by a Board of Chosen Freeholders whose five members are elected at-large in partisan elections on a staggered basis, with either one or two seats coming up for election each year. At an annual reorganization meeting held in the beginning of January, the board selects a Freeholder Director and Deputy Director from among its members, with day-to-day supervision of the operation of the county delegated to a County Administrator. As of 2014, Sussex County's Freeholders are Freeholder Director Richard Vohden (R, Green Township, 2016), Deputy Director Dennis J. Mudrick (R, Sparta Township, 2015), Phillip R. Crabb (R, Franklin, 2014), George Graham (R, Stanhope, 2016) and Gail Phoebus (R, Andover Township, 2015). Graham was chosen in April 2013 to fill the seat vacated by Parker Space, who had been chosen to fill a vacancy in the New Jersey General Assembly. Constitutional officers elected on a countywide basis are County Clerk Jeff Parrott (R, 2016), Sheriff Michael F. Strada (R, 2016) and Surrogate Gary R. Chiusano (R, filling the vacancy after the resignation of Nancy Fitzgibbons). The County Administrator is John Eskilson.
As of March 23, 2011, there were a total of 403 registered voters in Andover, of which 109 (27.0% vs. 16.5% countywide) were registered as Democrats, 152 (37.7% vs. 39.3%) were registered as Republicans and 142 (35.2% vs. 44.1%) were registered as Unaffiliated. There were no voters registered to other parties. Among the borough's 2010 Census population, 66.5% (vs. 65.8% in Sussex County) were registered to vote, including 84.3% of those ages 18 and over (vs. 86.5% countywide).
In the 2012 presidential election, Republican Mitt Romney received 143 votes (50.9% vs. 59.4% countywide), ahead of Democrat Barack Obama with 129 votes (45.9% vs. 38.2%) and other candidates with 8 votes (2.8% vs. 2.1%), among the 281 ballots cast by the borough's 400 registered voters, for a turnout of 70.3% (vs. 68.3% in Sussex County). In the 2008 presidential election, Republican John McCain received 139 votes (49.5% vs. 59.2% countywide) tied with Democrat Barack Obama with 139 votes (49.5% vs. 38.7%) and other candidates with 2 votes (0.7% vs. 1.5%), among the 281 ballots cast by the borough's 404 registered voters, for a turnout of 69.6% (vs. 76.9% in Sussex County). In the 2004 presidential election, Republican George W. Bush received 171 votes (55.5% vs. 63.9% countywide), ahead of Democrat John Kerry with 134 votes (43.5% vs. 34.4%) and other candidates with one vote (0.3% vs. 1.3%), among the 308 ballots cast by the borough's 421 registered voters, for a turnout of 73.2% (vs. 77.7% in the whole county).
In the 2013 gubernatorial election, Republican Chris Christie received 61.6% of the vote (106 cast), ahead of Democrat Barbara Buono with 32.6% (56 votes), and other candidates with 5.8% (10 votes), among the 173 ballots cast by the borough's 396 registered voters (1 ballot was spoiled), for a turnout of 43.7%. In the 2009 gubernatorial election, Republican Chris Christie received 117 votes (58.8% vs. 63.3% countywide), ahead of Democrat Jon Corzine with 61 votes (30.7% vs. 25.7%), Independent Chris Daggett with 18 votes (9.0% vs. 9.1%) and other candidates with 2 votes (1.0% vs. 1.3%), among the 199 ballots cast by the borough's 386 registered voters, yielding a 51.6% turnout (vs. 52.3% in the county).
Public school students in pre-kindergarten through eighth grade attend the Andover Regional School District, together with students from Andover Township. As of the 2014-15 school year, the district and its two schools had an enrollment of 852 students and 55.3 classroom teachers (on an FTE basis), for a student–teacher ratio of 15.4:1. Schools in the district (with 2014-15 enrollment data from the National Center for Education Statistics) are Florence M. Burd Elementary School (Grades PreK-4, 279 students) and Long Pond Middle School (Grades 5-8, 280 students).
Public school students in ninth through twelfth grades attend Newton High School in Newton, together with students from Andover Township and Green Township, as part of a sending/receiving relationship with the Newton Public School District. As of the 2014-15 school year, the high school had an enrollment of 773 students and 66.5 classroom teachers (on an FTE basis), for a student–teacher ratio of 11.6:1.
Since 1972, Lakeland Andover School has been operating as a therapeutic, nonprofit, private day school whose primary purpose is the education of emotionally and behaviorally challenged 7th - 12th grade students.
Formed in 1974, Andover has a municipal police department, currently under the leadership of Chief Eric Danielson.
As of May 2010, the borough had a total of 7.41 miles (11.93 km) of roadways, of which 1.92 miles (3.09 km) were maintained by the municipality, 3.18 miles (5.12 km) by Sussex County and 2.31 miles (3.72 km) by the New Jersey Department of Transportation.
U.S. Route 206 and County Route 517 pass through the borough.
Lakeland Bus Lines provides service operating along Interstate 80 between Newton, New Jersey and the Port Authority Bus Terminal in Midtown Manhattan.
As part of restoring train service via the Lackawanna Cut-Off, funding has been secured to rebuild a 7.3 miles (11.7 km) stretch of the railroad to a new station in Andover, which is projected to open in the fall of 2018.
Aeroflex-Andover Airport is located 2 miles (3.2 km) north of the central business district and Trinca Airport, 3 miles (4.8 km) southwest.
People who were born in, residents of, or otherwise closely associated with Andover include:Kenneth Burke (1897–1993), cultural and literary critic and philosopher; Harry and Tom Chapin's grandfather.
Newman E. Drake (1860–1930), founder of the Drake's baking company.
Rob Freeman (born 1981), member of Hidden in Plain View.