RANKING · 2020 CENSUS · 67 SHOWN OF 67

Most population lost, Pennsylvania counties · 2020

Pennsylvania counties that lost the most residents from the 2010 census to 2020, 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

01Westmoreland County, PAPA349,324-10,506+3103%

02Cambria County, PAPA128,968-10,207−2%

03Erie County, PAPA265,832-9,690−284%

04Fayette County, PAPA123,021-7,802−337%

05Mercer County, PAPA107,860-5,986+743%

06Indiana County, PAPA82,878-5,634+1348%

07Schuylkill County, PAPA145,085-5,240+133%

08Lawrence County, PAPA83,911-5,038+214%

09Susquehanna County, PAPA38,237-4,922−365%

10Crawford County, PAPA81,792-4,827−215%

11Venango County, PAPA49,346-4,530+149%

12Blair County, PAPA119,541-4,267+205%

13Somerset County, PAPA72,004-3,613−300%

14Armstrong County, PAPA63,698-3,383+212%

15Warren County, PAPA37,038-3,228+172%

16McKean County, PAPA38,984-3,018+153%

17Northumberland County, PAPA89,920-2,881+30%

18Clarion County, PAPA36,680-2,747−4262%

19Greene County, PAPA33,885-2,732−343%

20Bradford County, PAPA59,600-2,655−248%

21Columbia County, PAPA66,193-2,568−371%

22Beaver County, PAPA166,032-2,324−50%

23Union County, PAPA42,313-2,266−142%

24Wyoming County, PAPA25,790-2,207−55275%

25Bedford County, PAPA47,480-2,185−206%

26Lycoming County, PAPA112,587-1,923−244%

27Huntingdon County, PAPA43,001-1,821−228%

28Clinton County, PAPA37,870-1,788−344%

29Wayne County, PAPA51,703-1,667−121%

30Monroe County, PAPA167,179-1,515−104%

31Juniata County, PAPA23,403-1,127−151%

32Clearfield County, PAPA78,100-1,080−120%

33Potter County, PAPA15,897-1,061−178%

34Elk County, PAPA29,926-956−509%

35Tioga County, PAPA40,502-936−479%

36Forest County, PAPA6,614-743−616%

37Jefferson County, PAPA43,255-708+369%

38Sullivan County, PAPA5,856-588−230%

39Mifflin County, PAPA46,127-539−287%

40Cameron County, PAPA4,211-538−982%

41Carbon County, PAPA65,868-500−126%

42Fulton County, PAPA14,483-289−168%

43Montour County, PAPA17,868-131−126%

44Perry County, PAPA46,806-127−105%

45Snyder County, PAPA39,655+34−96%

46Pike County, PAPA62,808+1,166−94%

47Lackawanna County, PAPA216,502+1,459−125%

48Washington County, PAPA210,802+1,529−191%

49Adams County, PAPA107,594+2,445−81%

50Centre County, PAPA157,393+4,182−65%

51Luzerne County, PAPA332,126+4,676−153%

52Franklin County, PAPA160,652+6,314−23%

53Lebanon County, PAPA146,380+9,689+47%

54Butler County, PAPA200,169+9,901−55%

55Northampton County, PAPA324,411+15,216−24%

56Berks County, PAPA440,072+17,407−53%

57Delaware County, PAPA580,937+17,851+456%

58Dauphin County, PAPA293,351+18,301+31%

59Bucks County, PAPA647,828+21,289−62%

60York County, PAPA473,197+21,466−49%

61Cumberland County, PAPA277,270+24,063+31%

62Lehigh County, PAPA384,383+25,060+20%

63Allegheny County, PAPA1,225,035+27,230−150%

64Lancaster County, PAPA563,159+33,539−30%

65Chester County, PAPA557,116+35,527−38%

66Montgomery County, PAPA877,643+56,679−21%

67Philadelphia County, PAPA1,574,281+77,791−214%

SHOWING 1–67 OF 67

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UPDATED 2026-07-15 · DATA: US CENSUS BUREAU DECENNIAL CENSUS