RANKING · 2025 ESTIMATES · 67 SHOWN OF 67

Most population lost, Pennsylvania counties

Pennsylvania counties that lost the most residents from the 2020 census to 2025, by raw count of people rather than percentage. This list covers the 67 counties in Pennsylvania that qualify, ranked against each other statewide.

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SAME RANKING BYCities States Metros

YEAR2000 2010 2020 2025

RANKPLACESTATEPOPPOPULATION CHANGEVS 2000

01Philadelphia County, PAPA1,574,281-29,516−57%

02Allegheny County, PAPA1,225,035-25,543−53%

03Fayette County, PAPA123,021-5,783−276%

04Westmoreland County, PAPA349,324-5,339+1528%

05Erie County, PAPA265,832-5,044−196%

06Cambria County, PAPA128,968-4,504−57%

07Blair County, PAPA119,541-3,281+135%

08Mercer County, PAPA107,860-2,792+293%

09Clearfield County, PAPA78,100-2,462−147%

10Beaver County, PAPA166,032-2,183−53%

11Lawrence County, PAPA83,911-2,159+35%

12Crawford County, PAPA81,792-2,146−151%

13Somerset County, PAPA72,004-2,125−218%

14Greene County, PAPA33,885-2,069−284%

15Armstrong County, PAPA63,698-1,860+71%

16Northumberland County, PAPA89,920-1,727−22%

17Lycoming County, PAPA112,587-1,601−220%

18Warren County, PAPA37,038-1,549+30%

19McKean County, PAPA38,984-1,448+21%

20Jefferson County, PAPA43,255-1,237+719%

21Monroe County, PAPA167,179-1,148−103%

22Venango County, PAPA49,346-1,108−39%

23Huntingdon County, PAPA43,001-1,091−177%

24Elk County, PAPA29,926-1,064−555%

25Centre County, PAPA157,393-779−107%

26Clarion County, PAPA36,680-561−950%

27Tioga County, PAPA40,502-543−320%

28Potter County, PAPA15,897-499−137%

29Indiana County, PAPA82,878-368−5%

30Union County, PAPA42,313-368−107%

31Bradford County, PAPA59,600-367−120%

32Forest County, PAPA6,614-359−349%

33Cameron County, PAPA4,211-336−651%

34Wyoming County, PAPA25,790-279−7075%

35Montour County, PAPA17,868-268−153%

36Susquehanna County, PAPA38,237-197−111%

37Juniata County, PAPA23,403-106−105%

38Bedford County, PAPA47,480-97−105%

39Snyder County, PAPA39,655-81−109%

40Fulton County, PAPA14,483-73−117%

41Mifflin County, PAPA46,127-16−106%

42Sullivan County, PAPA5,856+16−96%

43Clinton County, PAPA37,870+420−43%

44Wayne County, PAPA51,703+548−93%

45Lackawanna County, PAPA216,502+606−111%

46Perry County, PAPA46,806+964−60%

47Carbon County, PAPA65,868+1,119−43%

48Bucks County, PAPA647,828+1,290−98%

49Washington County, PAPA210,802+1,453−186%

50Columbia County, PAPA66,193+1,466+54%

51Schuylkill County, PAPA145,085+2,036−191%

52Lebanon County, PAPA146,380+3,123−53%

53Adams County, PAPA107,594+3,742−71%

54Delaware County, PAPA580,937+4,107+28%

55Pike County, PAPA62,808+4,273−77%

56Franklin County, PAPA160,652+4,720−43%

57Butler County, PAPA200,169+6,406−71%

58Luzerne County, PAPA332,126+6,532−173%

59Dauphin County, PAPA293,351+6,950−50%

60Lehigh County, PAPA384,383+9,826−53%

61Lancaster County, PAPA563,159+10,175−79%

62Berks County, PAPA440,072+11,223−70%

63Northampton County, PAPA324,411+11,460−43%

64York County, PAPA473,197+16,759−60%

65Cumberland County, PAPA277,270+17,801−3%

66Montgomery County, PAPA877,643+21,090−71%

67Chester County, PAPA557,116+22,703−60%

SHOWING 1–67 OF 67

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU POPULATION ESTIMATES