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Population Review

Census ACS 2023 · 500 counties

Largest US Counties by Population

The largest US counties contain some of the nation's biggest metropolitan areas and function as economic engines that rival mid-sized countries. Los Angeles County alone has more residents than 40 US states. The five largest counties (LA, Cook, Harris, Maricopa, and San Diego) together contain over 26 million residents, roughly 8% of the US population. These large counties provide essential services, from public health systems to court administration, and their demographic shifts often foreshadow national trends. Many were once rural farmland before rapid post-war suburbanization transformed them into sprawling metropolitan areas. Their size creates governance challenges, diverse county commissions balance urban, suburban, and rural interests.

Key Findings

  • 1Los Angeles County, CA leads with a population of 9,848,406, followed by Cook County, IL (5,185,812) and Harris County, TX (4,758,579).
  • 2Skagit County, WA ranks last at 130,407, while Los Angeles County, CA leads at 9,848,406.
  • 3The national median across all states is 285,597 (Merced County, CA at the midpoint).
  • 4The top 10 states are: Los Angeles County, CA, Cook County, IL, Harris County, TX, Maricopa County, AZ, San Diego County, CA, Orange County, CA, Miami-Dade County, FL, Kings County, NY, Dallas County, TX, Riverside County, CA.

Full Ranking: Largest US Counties by Population

Source: Census ACS 2023 5-Year Estimates

#CountyStatePopulationMedian Income
1Yuma County, AZAZ207,685$60,417
2York County, SCSC288,559$83,060
3York County, PAPA459,312$82,238
4York County, MEME214,731$82,904
5Yolo County, CACA217,782$88,818
6Yellowstone County, MTMT167,340$74,400
7Yavapai County, AZAZ241,656$66,106
8Yakima County, WAWA256,605$68,015
9Wyandotte County, KSKS167,277$60,582
10Wright County, MNMN145,270$106,666
11Worcester County, MAMA861,664$93,561
12Wood County, OHOH131,795$73,124
13Winnebago County, WIWI171,357$72,873
14Winnebago County, ILIL283,289$64,363
15Wilson County, TNTN153,587$94,048
16Williamson County, TXTX643,889$108,309
17Williamson County, TNTN254,609$131,202
18Will County, ILIL698,450$107,799
19Whatcom County, WAWA228,432$80,989
20Westmoreland County, PAPA353,345$72,468
21Western Connecticut Planning Region, CTCT621,232$124,553
22Westchester County, NYNY996,888$118,411
23Weld County, COCO340,711$93,287
24Weber County, UTUT266,183$87,083
25Webb County, TXTX267,731$62,506
26Wayne County, MIMI1,773,767$59,521
27Waukesha County, WIWI409,040$104,100
28Washtenaw County, MIMI368,394$87,156
29Washoe County, NVNV491,770$85,600
30Washington County, WIWI137,320$95,851
31Washington County, UTUT189,827$76,411
32Washington County, TNTN134,693$61,051
33Washington County, PAPA209,778$77,487
34Washington County, OROR600,266$104,434
35Washington County, MNMN272,298$114,457
36Washington County, MDMD155,033$74,157
37Washington County, ARAR251,863$66,426
38Warren County, OHOH246,364$107,843
39Warren County, KYKY137,549$64,801
40Wake County, NCNC1,151,009$101,763
41Volusia County, FLFL568,229$66,581
42Virginia Beach city, VAVA457,066$90,685
43Ventura County, CACA838,259$107,327
44Vanderburgh County, ININ179,908$60,938
45Utah County, UTUT683,622$96,877
46Union County, NJNJ572,549$100,117
47Union County, NCNC244,975$99,243
48Ulster County, NYNY182,109$81,804
49Tuscaloosa County, ALAL234,036$63,947
50Tulsa County, OKOK673,708$67,317
51Tulare County, CACA475,774$69,489
52Trumbull County, OHOH201,367$55,088
53Travis County, TXTX1,307,625$97,169
54Tippecanoe County, ININ187,399$58,622
55Thurston County, WAWA296,640$93,985
56Tazewell County, ILIL130,555$76,704
57Taylor County, TXTX144,259$66,406
58Tarrant County, TXTX2,135,743$81,905
59Tangipahoa Parish, LALA135,218$57,256
60Sussex County, NJNJ145,117$114,316
61Sussex County, DEDE247,799$78,162
62Sumter County, FLFL137,536$73,297
63Sumner County, TNTN200,553$86,005
64Summit County, OHOH538,087$71,016
65Sullivan County, TNTN159,693$56,802
66Suffolk County, NYNY1,525,680$128,329
67Suffolk County, MAMA782,172$92,859
68Strafford County, NHNH131,743$86,564
69Stearns County, MNMN159,358$76,447
70Stark County, OHOH373,764$65,740
71Stanislaus County, CACA552,250$79,661
72Stafford County, VAVA160,520$133,792
73St. Tammany Parish, LALA269,331$79,277
74St. Lucie County, FLFL346,237$69,027
75St. Louis County, MOMO996,618$81,340
76St. Louis County, MNMN200,056$69,455
77St. Louis city, MOMO293,109$55,279
78St. Joseph County, ININ272,574$64,885
79St. Johns County, FLFL292,243$106,169
80St. Clair County, MIMI160,089$69,349
81St. Clair County, ILIL254,777$70,178
82St. Charles County, MOMO409,830$102,912
83Spotsylvania County, VAVA143,876$109,576
84Spokane County, WAWA544,323$73,513
85Spartanburg County, SCSC338,096$64,195
86Southeastern Connecticut Planning Region, CTCT279,025$84,185
87South Central Connecticut Planning Region, CTCT566,803$86,266
88Sonoma County, CACA485,642$102,840
89Somerset County, NJNJ346,203$135,960
90Solano County, CACA450,824$99,994
91Snohomish County, WAWA834,648$107,982
92Smith County, TXTX238,014$71,923
93Skagit County, WAWA130,407$85,474
94Shelby County, TNTN922,195$62,337
95Shelby County, ALAL226,955$93,543
96Shawnee County, KSKS178,315$66,043
97Shasta County, CACA181,554$71,931
98Seminole County, FLFL474,912$83,030
99Sedgwick County, KSKS524,810$67,675
100Scott County, MNMN152,957$120,247
101Scott County, IAIA174,302$76,363
102Schuylkill County, PAPA143,259$66,901
103Schenectady County, NYNY159,603$76,989
104Sarpy County, NENE194,051$101,402
105Saratoga County, NYNY237,075$99,653
106Sarasota County, FLFL449,011$80,633
107Santa Rosa County, FLFL193,719$88,968
108Santa Fe County, NMNM155,175$74,689
109Santa Cruz County, CACA266,021$109,266
110Santa Clara County, CACA1,903,297$159,674
111Santa Barbara County, CACA443,975$95,977
112Sangamon County, ILIL195,217$74,114
113Sandoval County, NMNM151,538$84,053
114San Mateo County, CACA745,100$156,000
115San Luis Obispo County, CACA281,486$93,398
116San Juan Municipio, 338,661$26,981
117San Joaquin County, CACA787,416$88,531
118San Francisco County, CACA836,321$141,446
119San Diego County, CACA3,282,782$102,285
120San Bernardino County, CACA2,187,816$82,184
121Salt Lake County, UTUT1,184,689$94,658
122Saginaw County, MIMI189,210$58,347
123Sacramento County, CACA1,584,047$88,724
124Rutherford County, TNTN351,591$82,588
125Rowan County, NCNC148,487$63,196
126Rockland County, NYNY338,936$110,631
127Rockingham County, NHNH317,163$113,927
128Rock Island County, ILIL142,995$66,768
129Rock County, WIWI163,944$74,390
130Riverside County, CACA2,449,909$89,672
131Richmond County, NYNY492,734$98,290
132Richmond County, GAGA206,040$53,197
133Richmond city, VAVA227,595$62,671
134Richland County, SCSC418,725$61,699
135Rensselaer County, NYNY160,341$86,663
136Rankin County, MSMS158,218$77,454
137Randolph County, NCNC145,322$59,047
138Randall County, TXTX143,791$80,905
139Ramsey County, MNMN544,438$81,004
140Racine County, WIWI196,888$75,331
141Queens County, NYNY2,330,124$84,961
142Pulaski County, ARAR398,949$60,385
143Pueblo County, COCO168,726$62,250
144Providence County, RIRI658,977$78,204
145Prince William County, VAVA484,625$128,873
146Prince George's County, MDMD955,584$100,708
147Porter County, ININ174,150$85,828
148Portage County, OHOH161,421$72,822
149Ponce Municipio, 134,676$18,827
150Polk County, IAIA497,441$81,621
151Polk County, FLFL760,961$63,644
152Plymouth County, MAMA531,889$109,698
153Placer County, CACA412,435$114,678
154Pitt County, NCNC172,279$58,851
155Pinellas County, FLFL960,565$70,293
156Pinal County, AZAZ449,219$77,588
157Pima County, AZAZ1,049,947$67,929
158Pierce County, WAWA924,106$96,632
159Pickens County, SCSC132,604$59,411
160Philadelphia County, PAPA1,582,432$60,698
161Peoria County, ILIL179,831$64,938
162Penobscot County, MEME153,571$63,248
163Paulding County, GAGA174,292$94,557
164Passaic County, NJNJ518,289$87,137
165Pasco County, FLFL588,758$67,384
166Parker County, TXTX158,079$102,099
167Palm Beach County, FLFL1,507,453$81,115
168Outagamie County, WIWI191,537$82,857
169Ouachita Parish, LALA158,916$51,241
170Ottawa County, MIMI298,614$87,144
171Osceola County, FLFL406,943$68,711
172Orleans Parish, LALA376,035$55,339
173Orange County, NYNY403,840$96,497
174Orange County, NCNC147,292$88,553
175Orange County, FLFL1,440,471$77,011
176Orange County, CACA3,164,063$113,702
177Onslow County, NCNC208,537$64,568
178Onondaga County, NYNY471,611$74,740
179Oneida County, NYNY229,645$68,819
180Olmsted County, MNMN163,425$93,494
181Oklahoma County, OKOK800,487$65,374
182Okaloosa County, FLFL214,281$79,097
183Ocean County, NJNJ646,434$86,411
184Oakland County, MIMI1,272,294$95,296
185Nueces County, TXTX352,829$66,021
186Northampton County, PAPA315,927$86,687
187Norfolk County, MAMA724,540$126,497
188Norfolk city, VAVA235,037$64,017
189Niagara County, NYNY211,341$67,809
190Newport News city, VAVA184,774$66,718
191New York County, NYNY1,627,788$104,553
192New Hanover County, NCNC231,214$72,892
193New Castle County, DEDE573,030$89,901
194Naugatuck Valley Planning Region, CTCT452,303$86,365
195Nassau County, NYNY1,388,138$143,408
196Napa County, CACA136,070$108,970
197Muskegon County, MIMI175,378$63,495
198Muscogee County, GAGA204,383$56,622
199Multnomah County, OROR803,863$86,247
200Morris County, NJNJ510,375$134,929
201Montgomery County, TXTX654,722$97,266
202Montgomery County, TNTN227,957$72,365
203Montgomery County, PAPA861,225$111,521
204Montgomery County, OHOH535,528$64,403
205Montgomery County, MDMD1,057,586$128,733
206Montgomery County, ALAL227,197$58,153
207Monterey County, CACA435,834$94,486
208Monroe County, PAPA167,784$82,374
209Monroe County, NYNY754,068$74,409
210Monroe County, MIMI155,001$75,272
211Monroe County, ININ139,822$63,372
212Monmouth County, NJNJ643,615$122,727
213Mohave County, AZAZ217,420$55,799
214Mobile County, ALAL413,162$58,119
215Minnehaha County, SDSD200,689$76,074
216Milwaukee County, WIWI927,656$62,118
217Midland County, TXTX171,496$93,984
218Middlesex County, NJNJ861,535$109,028
219Middlesex County, MAMA1,622,896$126,779
220Miami-Dade County, FLFL2,685,296$68,694
221Mesa County, COCO157,316$71,485
222Merrimack County, NHNH155,018$93,944
223Mercer County, NJNJ383,286$96,333
224Merced County, CACA285,597$65,044
225Medina County, OHOH183,049$92,660
226Mecklenburg County, NCNC1,130,906$83,765
227McLennan County, TXTX263,608$63,888
228McLean County, ILIL170,882$78,329
229McHenry County, ILIL311,366$102,836
230Maui County, HIHI164,632$95,076
231Martin County, FLFL160,464$80,701
232Marion County, OROR346,532$74,624
233Marion County, ININ971,822$63,450
234Marion County, FLFL387,697$58,535
235Marin County, CACA258,765$142,785
236Maricopa County, AZAZ4,491,987$85,518
237Marathon County, WIWI138,067$76,185
238Manatee County, FLFL416,020$75,792
239Mahoning County, OHOH227,063$55,576
240Madison County, ININ130,949$62,632
241Madison County, ILIL264,631$74,800
242Madison County, ALAL397,135$83,528
243Madera County, CACA158,790$75,496
244Macomb County, MIMI877,624$76,399
245Luzerne County, PAPA325,978$62,321
246Lucas County, OHOH428,748$60,095
247Lubbock County, TXTX314,633$63,367
248Lower Connecticut River Valley Planning Region, CTCT174,983$101,117
249Loudoun County, VAVA427,082$178,707
250Los Angeles County, CACA9,848,406$87,760
251Lorain County, OHOH314,588$70,693
252Livingston Parish, LALA145,583$78,617
253Livingston County, MIMI195,143$101,315
254Linn County, IAIA229,463$76,421
255Licking County, OHOH180,311$81,033
256Lexington County, SCSC300,370$75,014
257Leon County, FLFL295,335$65,074
258Lehigh County, PAPA375,408$77,493
259Lee County, FLFL792,692$73,099
260Lee County, ALAL177,663$61,123
261Lebanon County, PAPA143,592$76,350
262Larimer County, COCO363,561$91,364
263Lane County, OROR382,628$69,311
264Lancaster County, PAPA555,151$83,703
265Lancaster County, NENE323,673$72,625
266Lake County, OHOH232,101$77,952
267Lake County, ININ498,990$68,985
268Lake County, ILIL711,885$108,917
269Lake County, FLFL398,696$69,956
270Lafayette Parish, LALA245,075$67,660
271Lackawanna County, PAPA215,834$64,691
272Kootenai County, IDID177,736$77,034
273Knox County, TNTN487,401$71,662
274Kitsap County, WAWA276,581$98,546
275Kings County, NYNY2,646,306$78,548
276Kings County, CACA152,830$68,750
277King County, WAWA2,262,713$122,148
278Kern County, CACA910,433$67,660
279Kenton County, KYKY169,817$79,421
280Kent County, RIRI170,658$91,278
281Kent County, MIMI658,844$80,390
282Kent County, DEDE185,043$72,872
283Kenosha County, WIWI168,413$79,412
284Kendall County, ILIL135,053$110,474
285Kaufman County, TXTX160,718$88,606
286Kane County, ILIL516,097$100,678
287Kanawha County, WVWV178,198$58,887
288Kalamazoo County, MIMI261,437$70,525
289Johnston County, NCNC226,623$79,838
290Johnson County, TXTX188,820$81,826
291Johnson County, KSKS614,764$107,261
292Johnson County, ININ163,983$87,227
293Johnson County, IAIA154,881$74,721
294Jefferson Parish, LALA432,484$65,246
295Jefferson County, TXTX253,939$59,934
296Jefferson County, MOMO228,227$80,522
297Jefferson County, KYKY777,392$67,849
298Jefferson County, COCO579,715$107,800
299Jefferson County, ALAL669,744$64,589
300Jackson County, OROR222,563$71,443
301Jackson County, MSMS144,437$64,756
302Jackson County, MOMO717,021$67,178
303Jackson County, MIMI160,187$65,004
304Iredell County, NCNC191,800$78,678
305Ingham County, MIMI282,015$64,354
306Indian River County, FLFL163,856$71,049
307Imperial County, CACA179,319$56,393
308Humboldt County, CACA135,418$61,135
309Hudson County, NJNJ710,478$90,032
310Howard County, MDMD333,916$146,982
311Houston County, GAGA166,902$80,743
312Horry County, SCSC368,937$64,623
313Honolulu County, HIHI1,003,666$104,264
314Hinds County, MSMS222,494$49,966
315Hillsborough County, NHNH424,732$100,436
316Hillsborough County, FLFL1,489,634$75,011
317Hidalgo County, TXTX880,921$52,281
318Hernando County, FLFL201,512$63,193
319Henry County, GAGA245,417$81,612
320Henrico County, VAVA334,434$86,397
321Hennepin County, MNMN1,268,903$96,339
322Hendricks County, ININ179,379$99,988
323Hays County, TXTX256,429$85,827
324Hawaii County, HIHI203,684$77,215
325Harrison County, MSMS209,443$57,233
326Harris County, TXTX4,758,579$73,104
327Harnett County, NCNC136,503$69,012
328Harford County, MDMD262,509$111,317
329Hampton city, VAVA137,334$67,758
330Hampshire County, MAMA156,595$86,391
331Hampden County, MAMA462,853$70,535
332Hamilton County, TNTN370,913$72,568
333Hamilton County, OHOH827,878$70,816
334Hamilton County, ININ357,176$117,957
335Hall County, GAGA208,395$77,430
336Gwinnett County, GAGA966,972$84,823
337Guilford County, NCNC542,987$66,027
338Guadalupe County, TXTX178,368$93,776
339Greenville County, SCSC537,575$74,624
340Greene County, OHOH168,531$85,218
341Greene County, MOMO301,121$57,488
342Greater Bridgeport Planning Region, CTCT326,296$87,135
343Grayson County, TXTX139,988$70,455
344Gloucester County, NJNJ304,504$102,807
345Genesee County, MIMI404,087$60,673
346Gaston County, NCNC231,485$65,472
347Galveston County, TXTX354,721$85,348
348Fulton County, GAGA1,068,507$91,490
349Fresno County, CACA1,012,152$71,434
350Frederick County, MDMD280,341$120,458
351Franklin County, PAPA156,626$74,946
352Franklin County, OHOH1,321,635$73,795
353Fort Bend County, TXTX859,721$113,409
354Forsyth County, NCNC386,740$65,541
355Forsyth County, GAGA260,062$138,000
356Florence County, SCSC136,921$56,650
357Fayette County, KYKY321,122$67,631
358Fairfield County, OHOH161,289$87,069
359Fairfax County, VAVA1,144,474$150,113
360Essex County, NJNJ854,130$76,712
361Essex County, MAMA807,258$99,431
362Escambia County, FLFL323,275$65,715
363Erie County, PAPA269,544$61,476
364Erie County, NYNY950,044$71,175
365Ellis County, TXTX203,927$95,898
366Elkhart County, ININ206,868$65,617
367El Paso County, TXTX866,275$58,859
368El Paso County, COCO736,008$87,470
369El Dorado County, CACA192,299$106,190
370Ector County, TXTX163,206$71,031
371East Baton Rouge Parish, LALA452,821$63,075
372Duval County, FLFL1,007,189$68,447
373Dutchess County, NYNY297,144$97,273
374Durham County, NCNC329,405$79,501
375DuPage County, ILIL927,263$110,502
376Douglas County, NENE585,461$79,081
377Douglas County, GAGA146,141$80,764
378Douglas County, COCO368,283$145,737
379Dorchester County, SCSC164,322$76,896
380Doña Ana County, NMNM221,665$55,663
381District of Columbia, DCDC672,079$106,287
382DeSoto County, MSMS188,598$82,980
383Deschutes County, OROR203,026$87,640
384Denver County, COCO713,734$91,681
385Denton County, TXTX945,644$108,185
386Delaware County, PAPA576,195$88,576
387Delaware County, OHOH221,160$130,088
388DeKalb County, GAGA762,105$77,683
389Davis County, UTUT366,742$108,058
390Davidson County, TNTN709,846$75,664
391Davidson County, NCNC171,063$62,426
392Dauphin County, PAPA287,484$74,159
393Dane County, WIWI564,777$88,108
394Dallas County, TXTX2,603,816$74,149
395Dakota County, MNMN442,204$105,212
396Cuyahoga County, OHOH1,249,418$62,823
397Cumberland County, PAPA264,422$85,634
398Cumberland County, NJNJ152,915$64,499
399Cumberland County, NCNC336,749$58,780
400Cumberland County, MEME305,940$92,983
401Coweta County, GAGA150,071$94,142
402Cook County, ILIL5,185,812$81,797
403Contra Costa County, CACA1,161,458$125,727
404Comal County, TXTX174,552$99,015
405Columbia County, GAGA159,638$96,122
406Collin County, TXTX1,116,601$117,588
407Collier County, FLFL387,681$86,173
408Coconino County, AZAZ144,643$69,748
409Cobb County, GAGA769,152$98,712
410Cleveland County, OKOK297,545$74,446
411Clermont County, OHOH209,862$83,178
412Clayton County, GAGA298,771$58,507
413Clay County, MOMO255,566$86,150
414Clay County, FLFL223,436$86,094
415Clark County, WAWA510,516$94,948
416Clark County, OHOH135,445$60,846
417Clark County, NVNV2,293,764$73,845
418Clackamas County, OROR422,308$100,360
419Citrus County, FLFL158,693$55,355
420Chittenden County, VTVT168,831$94,310
421Chesterfield County, VAVA371,610$98,910
422Chester County, PAPA540,896$123,041
423Chesapeake city, VAVA251,153$94,189
424Cherokee County, GAGA274,539$105,442
425Chatham County, GAGA298,143$69,575
426Charlotte County, FLFL195,083$66,154
427Charleston County, SCSC414,711$84,320
428Charles County, MDMD168,710$120,592
429Champaign County, ILIL206,098$63,091
430Centre County, PAPA158,041$72,748
431Catawba County, NCNC162,051$64,544
432Cass County, NDND189,286$75,023
433Carroll County, MDMD174,318$115,876
434Carolina Municipio, 153,226$35,126
435Capitol Planning Region, CTCT969,029$91,541
436Canyon County, IDID242,405$72,355
437Canadian County, OKOK162,621$85,427
438Cameron County, TXTX423,192$51,334
439Camden County, NJNJ524,042$86,384
440Cambria County, PAPA132,355$56,292
441Calhoun County, MIMI133,846$60,385
442Calcasieu Parish, LALA208,668$67,849
443Caddo Parish, LALA232,973$50,067
444Cache County, UTUT137,031$78,292
445Cabarrus County, NCNC231,262$86,084
446Butte County, CACA209,470$68,574
447Butler County, PAPA195,870$86,775
448Butler County, OHOH389,910$81,194
449Burlington County, NJNJ464,226$105,271
450Buncombe County, NCNC271,790$70,578
451Bucks County, PAPA645,993$111,951
452Brunswick County, NCNC145,889$74,034
453Brown County, WIWI269,425$77,490
454Broward County, FLFL1,946,127$74,534
455Broome County, NYNY197,738$61,059
456Bronx County, NYNY1,419,250$49,036
457Bristol County, MAMA578,436$84,198
458Brevard County, FLFL620,533$75,817
459Brazos County, TXTX237,980$58,388
460Brazoria County, TXTX381,650$95,155
461Boulder County, COCO328,317$102,772
462Boone County, MOMO185,874$69,913
463Boone County, KYKY137,676$94,752
464Blount County, TNTN137,747$74,607
465Black Hawk County, IAIA130,693$64,581
466Bibb County, GAGA156,543$50,747
467Bexar County, TXTX2,037,344$70,571
468Berrien County, MIMI153,411$63,152
469Bernalillo County, NMNM674,357$66,514
470Berks County, PAPA429,989$77,684
471Berkeley County, SCSC238,723$82,327
472Bergen County, NJNJ954,717$123,715
473Benton County, WAWA210,224$87,316
474Benton County, ARAR294,541$89,879
475Bell County, TXTX379,811$66,051
476Beaver County, PAPA166,993$70,156
477Beaufort County, SCSC192,123$84,819
478Bayamón Municipio, 183,456$30,729
479Bay County, FLFL181,368$70,188
480Barnstable County, MAMA230,073$94,452
481Baltimore County, MDMD849,586$90,904
482Baltimore city, MDMD577,193$59,623
483Baldwin County, ALAL239,945$75,019
484Atlantic County, NJNJ274,704$76,819
485Arlington County, VAVA235,463$140,160
486Arapahoe County, COCO655,709$97,215
487Anoka County, MNMN367,095$98,764
488Anne Arundel County, MDMD590,936$120,324
489Anderson County, SCSC207,218$64,683
490Anchorage Municipality, AKAK289,069$98,152
491Allen County, ININ388,791$68,839
492Allegheny County, PAPA1,240,476$76,393
493Alexandria city, VAVA156,788$113,638
494Albany County, NYNY315,374$83,149
495Alameda County, CACA1,651,949$126,240
496Alamance County, NCNC174,286$64,445
497Alachua County, FLFL281,751$59,659
498Aiken County, SCSC171,949$67,940
499Adams County, COCO524,408$91,387
500Ada County, IDID508,052$88,907

Methodology

Rankings are based on American Community Survey (ACS) 2023 5-Year estimates from the US Census Bureau. All 50 states and the District of Columbia are included. The ACS surveys approximately 3.5 million households annually and provides detailed demographic, social, economic, and housing data. 5-Year estimates offer the most reliable data for state-level comparisons by averaging responses over a 60-month period. Percentages may not sum to 100% due to rounding.

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Frequently Asked Questions

Los Angeles County, CA has the highest population at 9,848,406, according to Census ACS 2023 data. Cook County, IL and Harris County, TX round out the top three.

Skagit County, WA has the lowest population at 130,407. Tazewell County, IL is second-lowest at 130,555.

The median across all 500 states is 285,597. Note that the national median and the state-level median are calculated differently, the state median represents the midpoint when all states are ranked.

This data comes from the American Community Survey (ACS) 2023 5-Year estimates published by the US Census Bureau. The ACS surveys approximately 3.5 million households annually and provides the most comprehensive demographic data available between decennial censuses.

Rankings are based on the latest available Census ACS data (currently 2023 5-Year estimates). The Census Bureau releases new ACS data annually, typically in September. Our data was last updated on April 12, 2026.

Rankings are based on American Community Survey (ACS) 2023 5-Year estimates from the US Census Bureau. All 50 states and the District of Columbia are included. The ACS surveys approximately 3.5 million households annually and provides detailed demographic, social, economic, and housing data. 5-Year estimates offer the most reliable data for state-level comparisons by averaging responses over a 60-month period. Percentages may not sum to 100% due to rounding.