Mifflin County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 46,143. Its county seat is Lewistown. The county was created on September 19, 1789, from parts of Cumberland County and Northumberland County. It was named for Thomas Mifflin, the first Governor of Pennsylvania. Mifflin County comprises the Lewistown, PA Micropolitan Statistical Area. The county is part of the Central Pennsylvania region of the state.

The county terrain is formed by the folded Appalachian Mountain ridges which run from southwest to northeast across the county. The terrain slopes to the northeast, with its highest point (Broad Mtn) 1.25 miles (2.01 km) East Northeast from the county's Northwest corner, just south of the county's border with Centre County. It measures 2,339 ft (713 m) Above sea level. The Juniata River flows northeast through the lower part of the county, exiting northeastward into Juniata County near Hawstone. The county has a total area of 415 square miles (1,070 km), of which 411 square miles (1,060 km) is land and 3.7 square miles (9.6 km) (0.9%) is water.

Mifflin County is located in, and has its boundaries defined by, the Ridge-and Valley Appalachian Mountains of Pennsylvania. The county is one of the 423 counties served by the Appalachian Regional Commission, and it is identified as part of the "Midlands" by Colin Woodard in his book American Nations: A History of the Eleven Rival Regional Cultures of North America.

US Route 322, a major divided highway, connects the county to the rest of the state on its route between Harrisburg and State College. US Route 522 also connects the county to the rest of the state on its route between Selinsgrove and Mount Union.

The county has a humid continental climate (Dfa/Dfb) and average temperatures in downtown Lewistown range from 27.8 °F in January to 72.7 °F in July.

Historical population

Census	Pop.	Note	%±
1790	7,562		—
1800	13,609		80.0%
1810	12,132		−10.9%
1820	16,618		37.0%
1830	21,690		30.5%
1840	13,092		−39.6%
1850	14,980		14.4%
1860	16,340		9.1%
1870	17,508		7.1%
1880	19,577		11.8%
1890	19,996		2.1%
1900	23,160		15.8%
1910	27,785		20.0%
1920	31,439		13.2%
1930	40,335		28.3%
1940	42,993		6.6%
1950	43,691		1.6%
1960	44,348		1.5%
1970	45,268		2.1%
1980	46,908		3.6%
1990	46,197		−1.5%
2000	46,486		0.6%
2010	46,682		0.4%
2020	46,143		−1.2%
2021 (est.)	46,136		0.0%
US Decennial Census 1790-1960 1900-1990 1990-2000 2010-2017

As of the 2010 U.S. census, there were 46,682 people and 18,743 households in the county. The population density was 113.6 people per square mile (43.9 people/km). There were 21,537 housing units at an average density of 52.4 units per square mile (20.2/km). The racial makeup of the county was 97.53% White, 0.64% Black or African American, 0.11% Native American, 0.36% Asian, 0.01% Pacific Islander, 0.31% from other races, and 1.03% from two or more races. 1.14% of the population were Hispanic or Latino of any race. 38.8% were of German, 19.2% American, 8.0% Irish and 7.5% English ancestry. 5.7% report speaking Pennsylvania Dutch, Dutch, or German at home.

There were 18,743 households, out of which 29.1% had children under the age of 18 living with them, 57.60% were married couples living together, 8.50% had a female householder with no husband present, and 29.90% were non-families. 26.00% of all households were made up of individuals, and 13.20% had someone living alone who was 65 years of age or older. The average household size was 2.49 and the average family size was 2.99.

The county population contained 23.1% under the age of 18, 2.2% from 18 to 19, 5.1% from 20 to 24, 10.4% from 25 to 34, 20.1% from 35 to 49, 20.6% from 50 to 64, and 18.5% who were 65 years of age or older. The median age was 39 years. The population was 48.93% male, and 51.07% female.

Mifflin County Racial Composition

Race	Num.	Perc.
White (NH)	43,343	94%
Black or African American (NH)	350	0.75%
Native American (NH)	51	0.11%
Asian (NH)	160	0.34%
Pacific Islander (NH)	0	0%
Other/Mixed (NH)	1,260	2.73%
Hispanic or Latino	979	2.12%

The Amish community in Mifflin County, established in 1791, had a total population of 3,905 people (in 30 congregations) in 2017, or 8.5% of the county's population.

The dominant form of speech in Mifflin County is the Central Pennsylvania accent. Almost everyone in Mifflin County speaks English. The Amish and some Mennonites speak Pennsylvania German, also known as Pennsylvania Dutch, a West Central German dialect, which is quite different from modern Standard German. The Amish and Mennonites also can speak English. Few non-Amish or Mennonites in Mifflin County today speak Pennsylvania German, but this was not true in the past.

The United States Office of Management and Budget has designated Mifflin County as the Lewistown, PA Micropolitan Statistical Area (μSA). As of the 2010 United States Census the micropolitan area ranked 10th most populous in the State of Pennsylvania and the 237th most populous in the United States with a population of 46,682.

• Rob Postal (R)
• Noah Wise (R)
• Kevin Kodish (D)

• Helen Kirk (R)
• Barbara Clemmons (R)
• Kendra Dunmire (D)

• District Attorney: Christopher Torquato (R)
• Sheriff: James Drayer (R)
• Treasurer: Diane Griffith (R)
• Register & Recorder: Ellen Amspacker (R)
• Coroner: Andrea Alcalde (R)
• Prothonotary: Tammy Stuck (R)

• David H. Rowe, Republican, Pennsylvania's 85th Representative District
• Kerry A. Benninghoff, Republican, Pennsylvania's 171st Representative District

(as of January 2023)

• Judy Ward, Republican, Pennsylvania's 30th Senatorial District

(as of January 2023)

• John Joyce, Republican, Pennsylvania's 13th congressional district

• John Fetterman, Democrat
• Bob Casey, Jr., Democrat

Mifflin County voters have been reliably Republican. In only one national election since 1940 has the county selected the Democratic Party candidate.

United States presidential election results for Mifflin County, Pennsylvania

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	17,184	77.69%	4,735	21.41%	201	0.91%
2020	16,670	77.37%	4,603	21.36%	274	1.27%
2016	14,094	75.28%	3,877	20.71%	750	4.01%
2012	11,939	72.73%	4,273	26.03%	204	1.24%
2008	10,929	65.89%	5,375	32.40%	283	1.71%
2004	11,726	69.79%	4,889	29.10%	187	1.11%
2000	9,400	64.32%	4,835	33.08%	379	2.59%
1996	6,888	50.21%	5,327	38.83%	1,503	10.96%
1992	6,300	42.89%	4,946	33.67%	3,442	23.43%
1988	8,170	62.49%	4,790	36.63%	115	0.88%
1984	9,106	63.35%	5,178	36.03%	89	0.62%
1980	7,541	55.78%	5,226	38.65%	753	5.57%
1976	7,698	54.56%	6,210	44.01%	201	1.42%
1972	9,989	72.10%	3,667	26.47%	199	1.44%
1968	8,133	55.33%	5,681	38.65%	884	6.01%
1964	6,006	40.43%	8,811	59.31%	39	0.26%
1960	10,315	67.85%	4,816	31.68%	72	0.47%
1956	8,638	62.94%	5,078	37.00%	9	0.07%
1952	8,620	59.22%	5,889	40.46%	47	0.32%
1948	5,666	53.84%	4,762	45.25%	95	0.90%
1944	6,205	51.92%	5,693	47.63%	54	0.45%
1940	6,352	47.48%	6,993	52.27%	34	0.25%
1936	6,867	41.56%	9,581	57.98%	77	0.47%
1932	5,525	58.95%	3,654	38.99%	193	2.06%
1928	8,932	86.97%	1,270	12.37%	68	0.66%
1924	4,780	66.92%	1,999	27.99%	364	5.10%
1920	3,872	58.93%	2,400	36.52%	299	4.55%
1916	2,105	47.37%	1,965	44.22%	374	8.42%
1912	654	14.60%	1,400	31.25%	2,426	54.15%
1908	2,902	59.39%	1,799	36.82%	185	3.79%
1904	3,054	66.10%	1,378	29.83%	188	4.07%
1900	2,594	56.48%	1,842	40.10%	157	3.42%
1896	2,662	54.22%	2,052	41.79%	196	3.99%
1892	2,175	49.82%	2,029	46.47%	162	3.71%
1888	2,321	51.46%	2,084	46.21%	105	2.33%

Major employers in Mifflin County include:

Most of the county is served by the Mifflin County School District, with the exception of Wayne Township and the boroughs of Newton-Hamilton and Kistler, which are part of the Mount Union Area School District.

• Mifflin County School District
• Mount Union Area School District (also in Huntingdon County)

Head Start is a federally and state funded preschool program for low income children. The program serves 3- and 4-year-olds. In order to participate the family income must be below federal poverty guidelines.

• Coleman Head Start Center
• McVeytown Head Start Center

• Sacred Heart provides a private, Catholic education from kindergarten through fifth grade.
• Belleville Mennonite School, Beth-El Christian Day School, and Valley View Christian School provide Mennonite education through grade twelve.
• Mifflin County Christian Academy located in Decatur Township provides Christian education from kindergarten through grade twelve as well as day care.
• Several Old Order Amish schools provide education through grade eight.

Mifflin County Academy of Science and Technology located in Lewistown provides post high school degrees in nursing, auto mechanics and electrical services and other technology driven careers.

The Lewistown branch of the South Hills School of Business and Technology offers associate degrees and other certifications in various areas of business, technology, and some health care. (Closed 2019)

The Penn State Learning Center in Lewistown offers both two-year and four-year degrees. Recently, the Learning Center opened a state-of-the-art science lab to be used by students attending the Lewistown Hospital School of Nursing.

• WLUI 670 AM- Lewistown (simulcast on W225CK, 92.9 FM)
• WKVA 920 AM- Lewistown (simulcast on W262DO, 100.3 FM)

• WRYV 88.7- Milroy
• WJRC 90.9- Lewistown
• WMRF 95.7- Lewistown
• WVNW 96.7- Burnham
• WCHX 105.5- Burnham

Mifflin County does not have a local television station but it is provided with local coverage from the following stations outside of the county from both the Harrisburg and Johnstown/Altoona markets:

• WHTM 27 Harrisburg (27.1 ABC, 27.2 ION, 27.3 GetTV, 27.4 Laff)
• WPMT 43 York (43.1 FOX, 43.2 AntennaTV)
• WHP 21 Harrisburg (21.1 CBS, 21.2 MyNetworkTV, 21.3 CW)
• WGAL 8 Lancaster (8.1 NBC, 8.2 MeTV)
• WTAJ 10 Altoona (10.1 CBS, 10.2 Escape, 10.3 Laff, 10.4 Grit)
• WJAC 6 Johnstown (6.1 NBC, 6.2 MeTV, 6.3 Comet, 6.4 CW)
• WATM 23 Altoona (23.1 ABC, 23.2 FOX, 23.3 ThisTV, 23.4 AntennaTV)
• WWCP 8 Johnstown (8.1 FOX, 8.2 ABC)
• WHVL 29 State College (29.1 MyNetworkTV, 29.2 Buzzr)

• Lewistown Sentinel
• County Observer
• The Valley Newspaper

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

Census-designated places are geographical areas designated by the US Census Bureau for the purpose of compiling demographic data. They are not actual jurisdictions under Pennsylvania law. Other unincorporated communities are listed here as well.

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

† county seat

Rank	City/Town/etc.	Municipal type	Population (2010 Census)
1	† Lewistown	Borough	8,338
2	Burnham	Borough	2,054
3	Belleville	CDP	1,827
4	Church Hill	CDP	1,627
5	Milroy	CDP	1,498
6	Highland Park	CDP	1,380
7	Yeagertown	CDP	1,050
8	Strodes Mills	CDP	757
9	Reedsville	CDP	641
10	Juniata Terrace	Borough	542
11	Allensville	CDP	503
12	Granville	CDP	440
13	Maitland	CDP	357
14	McVeytown	Borough	342
15	Kistler	Borough	320
16	Mattawana	CDP	276
17	Lumber City	CDP	255
18	Longfellow	CDP	215
19	Newton Hamilton	Borough	205
20	Cedar Crest	CDP	195
21	Atkinson Mills	CDP	174
22	Potlicker Flats	CDP	172
23	Barrville	CDP	160
24	Alfarata	CDP	149
25	Wagner	CDP	128
26	Siglerville	CDP	106

• National Register of Historic Places listings in Mifflin County, Pennsylvania

• Raymond Martin Bell, Mifflin County, Pennsylvania: Families and Records before 1800. Washington PA (1987)
• Raymond Martin Bell, Mifflin County, Pennsylvania, in the Revolution, 1775-1783. Washington PA (1993)
• Raymond Martin Bell, The Houses of Mifflin County, Pennsylvania. Washington PA (1970)
• Forest K Fisher, Mifflin County. Charleston SC: Arcadia Publishing (2008)
• I. Daniel Rupp, History of Mifflin County, Pennsylvania. Laughlintown PA: Southwest Pennsylvania Genealogical Services, n.d. [1983].
• John Martin Stroup, The Amish of the Kishacoquillas Valley, Mifflin County, Pennsylvania: When Did They Come, and Why? What of the Future? Lewistown PA: Mifflin County Historical Society (1965)
• John Martin Stroup and Raymond Martin Bell, The Genesis of Mifflin County Pennsylvania: Its Aborigines, Explorers, Early Settlement and Development, Indian Wars and The Revolution, and Formation as a County. Lewistown PA: Mifflin County Historical Society (1957)
• John Martin Stroup and Raymond Martin Bell, The People of Mifflin County, Pennsylvania, 1755-1798: Pioneer Settlers and Defenders of the Frontier During the Revolution. Lewistown, PA: Mifflin County Historical Society (1973)
• John Martin Stroup and Raymond Martin Bell, The Pioneers of Mifflin County, Pennsylvania: Who's Who in the Early Records with an Account of the Growth of the County before 1790. Lewistown PA: Mifflin County Historical Society (1942)
• The Cemeteries of Mifflin County, Pennsylvania. Lewistown PA: Mifflin County Historical Society (1977)
• Two Hundred Years: A Chronological List of Events in the History of Mifflin County, Pennsylvania. Lewistown PA: Mifflin County Historical Society (1957)

• Pennsylvania Department of Transportation, Bureau of Planning and Research, Geographic Information Division, "2005 General Highway Map of Juniata and Mifflin Counties". Note: shows boroughs, townships, roads, villages, some streams. URL accessed on April 5, 2006.
• JuniataRiverValley.org Visitor Bureau

40°37′N 77°37′W / 40.61°N 77.62°W / 40.61; -77.62