As of the census of 2000, there were 2,415 people, 900 households, and 682 families residing in the CDP. The population density was . There were 939 housing units at an average density of . The racial makeup of the CDP was 97.1% White, 0.8% African American, 1.0% Asian, 0.3% from other races, and 0.9% from two or more races. Hispanic or Latino of any race were 0.8% of the population.
There were 900 households, out of which 38.3% had children under the age of 18 living with them, 64.4% were married couples living together, 8.6% had a female householder with no husband present, and 24.2% were non-families. 21.2% of all households were made up of individuals, and 7.7% had someone living alone who was 65 years of age or older. The average household size was 2.61 and the average family size was 3.05.
In the CDP, the population was spread out, with 27.0% under the age of 18, 5.1% from 18 to 24, 33.0% from 25 to 44, 22.3% from 45 to 64, and 12.6% who were 65 years of age or older. The median age was 37 years. For every 100 females, there were 92.6 males. For every 100 females age 18 and over, there were 86.3 males.
The median income for a household in the CDP was $55,625, and the median income for a family was $66,452. Males had a median income of $45,306 versus $29,659 for females. The per capita income for the CDP was $22,827. None of the families and 0.9% of the population were living below the poverty line, including no under eighteens and none of those over 64.
Campbelltown tornadoes
On July 14, 2004, around 3 pm, a tornado warning was issued by the National Weather Service for Lebanon County. A few moments later, an F3 tornado with winds over struck the extreme southeast part of the village. No deaths occurred, but several minor to moderate injuries were treated. It is the largest and most expensive tornado to have struck Lebanon County.
On June 22, 2010, an EF0 tornado touched down in Campbelltown. This weak tornado did not cause as much damage as the one in 2004.
Village Square Project
On October 23, 2023, Ethos Residential made public their plans to create a proposed village square project in the village of Campbelltown. Three properties along U.S. 322, formerly known as the Alger Farm, are envisioned for the new 15.15-acre mixed-use development.
The proposed architecture is loosely based on that used throughout historic Campbelltown and will be designed to function as a traditional town square.
HMS Campbeltown
was a World War II Royal Navy destroyer used in the St Nazaire Raid whose bell was donated to the municipality after the war.
thumb|British Commander Robert Boddy, Campbelltown representative Abner Spangler, British consul-general H. C. McClelland, and Lebanon Mayor William Focht at the bell’s gifting ceremony in 1950.
In 1940, the Lend-Lease agreement between the United States and the United Kingdom was signed that gave 50 of the United States Navy destroyer in exchange for leases on British bases in the Western Hemisphere. One of these ships, USS Buchanan, launched in 1919, became HMS Campbeltown. Its namesake was Campbeltown of Argyll County, Scotland, and its American counterpart, was Campbelltown of Lebanon County, Pennsylvania.
After the war, the bell resided in the Scottish Campbeltown until 1950, when British consul-general H. C. McClelland wrote a letter to the mayor of Lebanon announcing that the ship's bell was being bequeathed to the city in recognition of a special bond between the town and the United Kingdom. The bell sits in the South Londonderry Township municipal building as a symbol of Campbelltown. The bell was returned to the town on June 21, 2011 when HMS Campbeltown was decommissioned. A new Type 31 HMS Campbeltown was announced as part of the new Inspiration class of frigates for the Royal Navy on May 19, 2021.