Dauphin County (/ˈdɔːfɪn/; Pennsylvania Dutch: Daffin Kaundi) is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 286,401. The county seat is Harrisburg, Pennsylvania's state capital and ninth-most populous city. The county was created on March 4, 1785, from part of Lancaster County and was named after Louis Joseph, Dauphin of France, the first son of King Louis XVI. The county is part of the South Central Pennsylvania region of the state.

Dauphin County is included in the Harrisburg–Carlisle Metropolitan Statistical Area.

Located within the county is Three Mile Island Nuclear Generating Station, site of the 1979 nuclear core meltdown. The nuclear power plant closed in 2019.

According to the U.S. Census Bureau, the county has a total area of 558 square miles (1,450 km), of which 525 square miles (1,360 km) is land and 33 square miles (85 km) (5.9%) is water. The county is bound to its western border by the Susquehanna River (with the exception of a small peninsula next to Duncannon). The area code is 717 with an overlay of 223.

• Northumberland County (north)
• Schuylkill County (northeast)
• Lebanon County (east)
• Lancaster County (south)
• York County (southwest)
• Cumberland County (west)
• Perry County (west)
• Juniata County (northwest)

Most of the county by area has a humid continental climate (Dfa except for some Dfb in highlands.) The inclusion of temperature numbers for the past decade shows some lower-lying areas, including Harrisburg, to have a humid subtropical climate (Cfa.) The hardiness zone is 7a except in some higher northern areas where it is 6b and a few very small areas along the river below the city including the airport where it is 7b. [1]

Historical population

Census	Pop.	Note	%±
1790	18,155		—
1800	22,270		22.7%
1810	31,883		43.2%
1820	21,653		−32.1%
1830	25,243		16.6%
1840	30,118		19.3%
1850	35,754		18.7%
1860	46,756		30.8%
1870	60,740		29.9%
1880	76,148		25.4%
1890	96,977		27.4%
1900	114,443		18.0%
1910	136,152		19.0%
1920	153,116		12.5%
1930	165,231		7.9%
1940	177,410		7.4%
1950	197,784		11.5%
1960	220,255		11.4%
1970	223,834		1.6%
1980	232,317		3.8%
1990	237,813		2.4%
2000	251,805		5.9%
2010	268,100		6.5%
2020	286,401		6.8%
2023 (est.)	289,234		1.0%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010,< 2020

This section needs to be updated. The reason given is: Newer information is available from the 2020 Census report. Please help update this article to reflect recent events or newly available information. (September 2021)

As of the 2010 census, the county was 72.7% White, 18.0% Black or African American, 0.2% Native American, 3.2% Asian, and 3.1% were two or more races. 7.0% of the population were of Hispanic or Latino ancestry.

As of the census of 2000, there were 251,798 people, 102,670 households, and 66,119 families residing in the county. The population density was 479 inhabitants per square mile (185/km). There were 111,133 housing units at an average density of 212 units per square mile (82/km). The racial makeup of the county was 77.11% White, 16.91% Black or African American, 0.16% Native American, 1.96% Asian, 0.03% Pacific Islander, 1.97% from other races, and 1.85% from two or more races. 4.13% of the population were Hispanic or Latino of any race. 29.2% were of German, 7.5% Irish, 7.3% American and 7.2% Italian ancestry. 91.8% spoke English and 3.9% Spanish as their first language.

According to 2005 estimates, 73.9% of the county's population was non-Hispanic whites. 17.8% of the population was African-Americans. 2.5% were Asians. Latinos now were 5.0% of the population.

In 2000 there were 102,670 households, out of which 29.70% had children under the age of 18 living with them, 47.60% were married couples living together, 12.90% had a female householder with no husband present, and 35.60% were non-families. 30.00% of all households were made up of individuals, and 10.30% had someone living alone who was 65 years of age or older. The average household size was 2.39 and the average family size was 2.98.

In the county, the population was spread out, with 24.30% under the age of 18, 7.60% from 18 to 24, 30.10% from 25 to 44, 23.80% from 45 to 64, and 14.20% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 92.30 males. For every 100 females age 18 and over, there were 88.80 males.

A study by Echelon Insights found Dauphin County to be the most typical county in America, with its 2016 presidential vote, median income, higher education rate, and religiosity all very close to the national averages.

Dauphin County Racial Composition

Race	Num.	Perc.
White (NH)	175,175	61.16%
Black or African American (NH)	48,404	17%
Native American (NH)	396	0.14%
Asian (NH)	17,183	6%
Pacific Islander (NH)	88	0.03%
Other/Mixed (NH)	13,904	4.85%
Hispanic or Latino	31,251	11%

Dauphin County is home to an Amish community that resides in the Lykens Valley in the northern part of the county, consisting of eight church districts. The community was settled by Amish from Lancaster County seeking cheaper land.

The United States Office of Management and Budget has designated Dauphin County as the Harrisburg-Carlisle, PA Metropolitan Statistical Area (MSA). As of the 2010 U.S. Census the metropolitan area ranked 5th most populous in the State of Pennsylvania and the 96th most populous in the United States with a population of 549,475. Dauphin County is also a part of the larger Harrisburg–York–Lebanon combined statistical area (CSA), which combines the populations of Dauphin County as well as Adams, Cumberland, Lebanon, Perry and York Counties in Pennsylvania. The combined statistical area ranked the 5th most populous in Pennsylvania and 43rd most populous in the nation with a population of 1,219,422.

United States presidential election results for Dauphin County, Pennsylvania

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2020	66,408	44.90%	78,983	53.40%	2,510	1.70%
2016	60,863	46.18%	64,706	49.10%	6,214	4.72%
2012	57,450	46.22%	64,965	52.26%	1,886	1.52%
2008	58,238	44.85%	69,975	53.89%	1,632	1.26%
2004	65,296	53.87%	55,299	45.62%	613	0.51%
2000	53,631	53.28%	44,390	44.10%	2,637	2.62%
1996	44,417	47.78%	40,936	44.03%	7,618	8.19%
1992	45,479	45.98%	36,990	37.40%	16,441	16.62%
1988	48,917	57.77%	35,079	41.43%	681	0.80%
1984	54,330	61.28%	33,576	37.87%	752	0.85%
1980	44,039	56.18%	27,252	34.77%	7,096	9.05%
1976	46,819	56.33%	34,342	41.32%	1,961	2.36%
1972	54,307	69.38%	22,587	28.86%	1,376	1.76%
1968	48,394	59.17%	25,480	31.15%	7,914	9.68%
1964	42,718	47.77%	46,119	51.57%	594	0.66%
1960	61,726	64.22%	33,962	35.33%	427	0.44%
1956	61,342	67.45%	29,226	32.14%	375	0.41%
1952	58,385	65.12%	30,985	34.56%	286	0.32%
1948	46,861	62.16%	27,729	36.78%	796	1.06%
1944	44,725	59.05%	30,684	40.51%	333	0.44%
1940	42,394	52.35%	38,305	47.30%	282	0.35%
1936	39,598	47.42%	43,256	51.80%	644	0.77%
1932	36,278	60.31%	22,412	37.26%	1,462	2.43%
1928	49,108	83.78%	9,115	15.55%	394	0.67%
1924	27,838	68.04%	9,004	22.01%	4,074	9.96%
1920	26,094	65.36%	11,990	30.03%	1,839	4.61%
1916	13,954	52.16%	11,483	42.92%	1,315	4.92%
1912	6,012	23.29%	7,470	28.93%	12,337	47.78%
1908	15,637	63.38%	7,546	30.59%	1,488	6.03%
1904	16,508	72.61%	5,040	22.17%	1,186	5.22%
1900	14,673	64.23%	7,390	32.35%	783	3.43%
1896	14,752	66.84%	6,584	29.83%	733	3.32%
1892	11,010	57.47%	7,520	39.25%	627	3.27%
1888	10,852	57.66%	7,684	40.82%	286	1.52%
1884	9,394	58.46%	6,378	39.69%	298	1.85%
1880	8,573	55.21%	6,619	42.62%	337	2.17%

Dauphin County was historically a Republican stronghold, like most of south-central Pennsylvania. It was long one of the more conservative urban counties in the nation, having only supported a Democrat for president twice from 1880 to 2004. The only breaks in this trend were in 1936 and 1964, which were national 400-electoral vote Democratic landslides.

However, there has been a decided shift toward the Democrats in national and statewide elections in recent years. This culminated when the Democrats overtook the Republicans in countywide registration during the summer of 2008.

Bob Casey Jr. carried the county in the 2006 Senate election when he unseated Rick Santorum. According to the Dauphin County Board of Elections, in 2008 Barack Obama became the first Democratic presidential candidate to carry Dauphin County since 1964, receiving 9.0% more of the vote than John McCain. It was also only the third time Dauphin County had supported a Democrat for president since 1936. Obama won Dauphin with a slightly reduced majority in 2012, while Hillary Clinton won it with a narrow plurality in 2016. It is now the only blue county in the traditionally powerfully Republican Susquehanna Valley.

In 2023, with the election of newcomer Justin Douglas to join George Hartwick, III, the Democrats took a majority on the Board of County Commissioners for the first time in nearly 100 years. That same year, Democrat Bridget Whitley was elected Clerk of Courts as the first Democratic row officer, while the remaining row offices remained Republican. Three of the state house seats are held by Democrats. Republicans control two state house seats as well as both of the state senate seats and the congressional seat. Most local elected officials are also Republican, by a margin of 3 to 1. This is because most of the Democratic gains have been in already heavily Democratic Harrisburg, which has had a Democratic mayor since 1982 and has been represented in the state house by a Democrat since 1975. In contrast, the suburbs and rural areas are among the most Republican areas of Pennsylvania.

As of July 29, 2024, 44.0% of registered voters in the county were Democrats, 38.6% Republicans, 13.3% non-affiliated, and 4.1% other party.

Party registration stats according to the Secretary of State's office:

Voter Registration and Party Enrollment
Party		Number of Voters	Percentage
	Democratic	86,237	43.98%
	Republican	75,704	38.61%
	Independent	26,129	13.33%
	Third parties	7,986	4.07%
Total		196,056	100%

• George P. Hartwick III, Chairman, Democrat
• Justin Douglas, Vice Chairman, Democrat
• Mike Pries, Secretary, Republican

• John DiSanto, Republican, 15th district
• Greg Rothman, Republican, 34th district

• Scott Perry, Republican, 10th district

Senator	Party
Bob Casey	Democrat
John Fetterman	Democrat

School districts include:

Several public charter schools are established in Dauphin County

• Infinity Charter School
• Sylvan Heights Science Charter School
• Capital Area School for the Arts
• Premier Arts and Science Charter School

The Capital Area Intermediate Unit 15 is a state approved education agency that offers: school districts, charter schools, private schools, and home school students, a variety of services including: a completely developed K–12 curriculum that is mapped and aligned with the Pennsylvania Academic Standards (available online), shared services, a group purchasing program and a wide variety of special education and special needs services.

The Dauphin County Library System provides library service to the residents of the county through a main central library in the state capital and county seat of Harrisburg, Pennsylvania and eight branch libraries. DCLS is a private, non-profit corporation. It is governed by a 17-member Board of Trustees, five appointed annually by the Dauphin County Commissioners, and twelve elected for three-year terms. The Library is a member of the Pennsylvania library system.

As reported by the National Center for Educational Statistics

The largest employers in Dauphin County in 2019 were:

• Commonwealth Government
• Milton S. Hershey Medical Center
• The Hershey Company
• Hershey Entertainment & Resorts Co.
• UPMC Pinnacle Hospitals
• Federal Government
• Pennsylvania State University
• PHEAA – Pennsylvania Higher Education Assistance Agency
• United Parcel Service Inc
• TYCO Electronics Corp.

There are two Pennsylvania state parks in Dauphin County.

• Boyd Big Tree Preserve Conservation Area
• Joseph E. Ibberson Conservation Area

Under Pennsylvania law, there are four types of incorporated municipalities: cities, boroughs, townships, and, in at most two cases, towns. The following cities, boroughs and townships are located in Dauphin County:

• Harrisburg (county seat)

• Berrysburg
• Dauphin
• Elizabethville
• Gratz
• Halifax
• Highspire
• Hummelstown
• Lykens
• Middletown
• Millersburg
• Paxtang
• Penbrook
• Pillow
• Royalton
• Steelton
• Williamstown

Census-designated places are geographical areas designated by the U.S. Census Bureau for the purposes of compiling demographic data. They are not actual jurisdictions under Pennsylvania law. Other unincorporated communities, such as villages, may be listed here as well.

The population ranking of the following table is based on the 2010 census of Dauphin County.

† county seat

Rank	City/Town/etc.	Municipal type	Population (2010 Census)
1	† Harrisburg (State Capital)	City	49,528
2	Hershey	CDP	14,257
3	Colonial Park	CDP	13,229
4	Progress	CDP	9,765
5	Middletown	Borough	8,901
6	Linglestown	CDP	6,334
7	Steelton	Borough	5,990
8	Paxtonia	CDP	5,412
9	Hummelstown	Borough	4,538
10	Rutherford	CDP	4,303
11	Skyline View	CDP	4,003
12	Lawnton	CDP	3,813
13	Penbrook	Borough	3,008
14	Millersburg	Borough	2,557
15	Highspire	Borough	2,399
16	Lykens	Borough	1,799
17	Paxtang	Borough	1,561
18	Elizabethville	Borough	1,510
19	Bressler	CDP	1,437
20	Williamstown	Borough	1,387
21	Palmdale	CDP	1,308
22	Enhaut	CDP	1,007
23	Wiconsico	CDP	921
24	Royalton	Borough	907
25	Halifax	Borough	841
26	Dauphin	Borough	791
27	Gratz	Borough	765
28	Oberlin	CDP	588
29	Lenkerville	CDP	550
30	Union Deposit	CDP	407
31	Berrysburg	Borough	368
32	Pillow	Borough	298

• Milton S. Hershey (1857–1945), founder of The Hershey Company and the town of Hershey
• H.B. Reese (1879–1956), inventor of Reese's Peanut Butter Cups
• Samuel B. Garver (1839–1911), an Illinois state representative, businessman, and farmer, was born in Dauphin County.
• Nicholas H. Heck (1882–1953), a geophysicist, seismologist, oceanographer, hydrographic surveyor, and United States Coast and Geodetic Survey officer, was born in Dauphin County in Heckton Mills, near Heckton.
• Newt Gingrich (1943–), former speaker of the United States House of Representatives, was born in Harrisburg and lived in Hummelstown.
• Michelle Wolf (1985–), comedian, was born and lived in Dauphin County.
• Christian Pulisic (1998–), soccer player who plays for Chelsea F.C. of England's Premier League and the United States men's national team was born in Hershey.
• Micah Parsons (1999–), football linebacker.
• Richard L. Schlegel (1927–2006), LGBT rights activist; born in Berrysburg and lived in Harrisburg.

• Hummelstown brownstone
• National Register of Historic Places listings in Dauphin County, Pennsylvania

• Dauphin County official website

40°25′N 76°47′W / 40.41°N 76.79°W / 40.41; -76.79