|— Town —|
|• Type||Selectman-town meeting|
|• First selectman||Paul J. DeStefano|
|• Total||46.4 sq mi (120.2 km2)|
|• Land||44.0 sq mi (114.0 km2)|
|• Water||2.3 sq mi (6.0 km2)|
|Elevation||322 ft (98 m)|
|• Density||174/sq mi (67/km2)|
|Time zone||Eastern (UTC-5)|
|• Summer (DST)||Eastern (UTC-4)|
|ZIP code||06424, 06438, 06441|
|GNIS feature ID||0213439|
According to the United States Census Bureau, the town has a total area of 46.3 square miles (120 km2), of which, 44.0 square miles (114 km2) of it is land and 2.3 square miles (6.0 km2) of it (5.01%) is water. It is located in the Connecticut River Valley with a majority of the town's eastern border along the Connecticut River. However, part of the border is the Salmon River on the east side, which causes the Connecticut river to divide the community of Haddam Neck from the rest of the town. Haddam is the only town in Connecticut with residents on both sides of the river, however there is no modern bridge or ferry within the town limits.
Villages and neighborhoods 
In addition to the town center, Haddam Center, the town also includes five villages, including Haddam Neck, Hidden Lake, Higganum, Shailerville, and Tylerville. The neighborhood of Ponset is also within the town's borders.
As of the census of 2000, there are 7,157 people, 2,701 households, and 2,101 families residing in the town. The population density is 162.5 inhabitants per square mile (62.8/km²). There are 2,822 housing units at an average density of 24.7 persons/km² (64.1 persons/mi²). The racial makeup of the town is 96.86% White, 1.03% African American, 0.11% Native American, 0.82% Asian, 0.03% Pacific Islander, 0.17% from other races, and 0.98% from two or more races. 1.06% of the population are Hispanic or Latino of any race.
There are 2,701 households out of which 34.5% have children under the age of 18 living with them, 68.1% are married couples living together, 6.9% have a woman whose husband does not live with her, and 22.2% are non-families. 18.1% of all households are made up of individuals and 7.0% have someone living alone who is 65 years of age or older. The average household size is 2.64 and the average family size is 3.00.
In the town the population is spread out with 24.7% under the age of 18, 5.0% from 18 to 24, 30.2% from 25 to 44, 30.4% from 45 to 64, and 9.7% who are 65 years of age or older. The median age is 40 years. For every 100 females there are 102.0 males. For every 100 females age 18 and over, there are 97.8 males.
The median income for a household in the town is $78,571, and the median income for a family is $87,026. Males have a median income of $50,500 versus $37,447 for females. The per capita income for the town is $30,519. 3.5% of the population and 1.5% of families are below the poverty line. Out of the total people living in poverty, 4.6% are under the age of 18 and 7.2% are 65 or older.
|Voter Registration and Party Enrollment as of October 25, 2005|
|Party||Active Voters||Inactive Voters||Total Voters||Percentage|
Haddam has many educational facilities consisting of all elementary, junior, and senior high schools. The town is a part of a Regional District 17 which comprises Haddam, Higganum, neighboring town Killingworth and also Haddam Neck, a part of Haddam that is separated by the Connecticut River and East Haddam. It is the only town in the United States without a bridge to connect the separated parts and also the only town in Connecticut to be separated by a river.
The three elementary schools in the district are:
Haddam Elementary School - located in Haddam, CT
Burr District Elementary School - located in Higganum, CT
Killingworth Elementary School - located in Killingworth, CT
The district high school,Haddam-Killingworth High School, is located in Higganum, CT and houses all students from 9th grade and above. The high school is part of a complex and shares facilities with the old attached district middle school. The Intermediate School, Haddam-Killingworth Middle School, is located in the town of Killingworth and houses 5th grade - 8th grade. Initially, the plan was to have the old Middle School complex become a part of the Haddam Killingworth HS. The old Middle School part of the complex was converted into a district-run daycare facility, the main offices of the district administration, and also houses the local trooper station.
The high school houses between 580 and 720 students depending on the year. Some students from the district middle school end up transferring to area religious, private, or magnet schools. One nearby option for students is Xavier (boys)or Mercy (girls), both are Catholic High Schools in neighboring Middletown, CT. The Haddam Killingworth's mascot is the Cougar with school colors of blue and gold.
In recent years it has been praised for its field hockey, soccer, baseball and cross country teams. The school also has many art & music offerings and has students annually in regional and national competitions.
Notable residents past and present 
- Samuel Arnold (Connecticut) (1806–1869), US Congressman was born and died in Haddam.
- David Brainerd (1718–1747), missionary, was born in Haddam.
- Illeana Douglas (1965-), actress, director, screenwriter, and producer grew up in Haddam.
- David Dudley Field I (1781–1867), Congregational minister and author lived in Haddam for 22 years.
- David Dudley Field II (1805–1894), lawyer and law reformer and US Congressman was born in Haddam. Brother to Stephen Johnson Field.
- Stephen Johnson Field (1816–1899), Associate Justice of the Supreme Court of the United States was born in Haddam.
- Asahel W. Hubbard (1819–1879), judge and US Congressman for Iowa was born in Haddam.
- David McDowell (1963-), psychiatrist
- Alexander Shaler (1827–1911), General for the Union Army also the founder of the National Rifle Association was born in Haddam.
- Venture Smith (1729–1805), Author of one of the earliest American slave narratives.
Literary references 
- The "thin men of Haddam" are apostrophized in stanza seven of "Thirteen Ways of Looking at a Blackbird" by Wallace Stevens:
- O thin men of Haddam,
- Why do you imagine golden birds?
- Do you not see how the blackbird
- Walks around the feet
- Of the women about you?
Notable locations and historic sites 
- Connecticut Yankee Nuclear Power Plant
- Camp Bethel - a historic religious camp at 124 Camp Bethel Road, built in 1877 and added to the National Register of Historic Places (NRHP) in 2007
- The town center village, listed as the Haddam Center Historic District on the NRHP
- James Hazelton House, NRHP-listed
- U.S. Census Bureau Population Estimates
- "Registration and Party Enrollment Statistics as of October 25, 2005" (PDF). Connecticut Secretary of State. Archived from the original on 2006-09-23. Retrieved 2006-10-02.
- "National Register Information System". National Register of Historic Places. National Park Service. 2009-03-13.