List of the most populous counties in the United States

This is a list of the 100 most populous counties in the United States based on the national decennial US census conducted on April 1, 2010 and subsequent mid-2010 and mid-2019 official estimates released by the United States Census Bureau (USCB).

A map of the counties and county equivalents of the United States. The 100 most populous counties are highlighted, with counties having more than one million residents in orange, and counties having fewer than one million residents in green, based on the results of the April 1, 2010 United States census.

Many of the counties on the list include major cities or metropolitan areas in all parts of the United States. Six of the listed counties have consolidated city and county government, namely the City and County of Honolulu, Metropolitan Government of Nashville and Davidson County, Tennessee, City and County of Philadelphia, City and County of San Francisco, City of Jacksonville and Duval County and City and County of Denver.[1][2][3] New York County, Bronx County, Kings County, Queens County, and Richmond County, are coterminous with the respective boroughs of New York City, and fall under the jurisdiction of the combined city government.

List

This list lists the most populous US counties and the District of Columbia sorted according to the mid-2018 official estimate by the United States Census Bureau (USCB).

Rank	County	State	Land area		April 1, 2010 census	July 1, 2019 official estimate	Mid-2010 to mid-2018 change		County seat
			km^2[4]	mi^2[5]			absolute	%
1	Los Angeles	California	10,509.87	4,057.88	9,818,605	10,039,107	220,502	2.25	Los Angeles
2	Cook	Illinois	2,448.38	945.33	5,194,675	5,150,233	-44,442	-0.86	Chicago
3	Harris	Texas	4,411.99	1,703.48	4,092,459	4,713,325	620,866	15.17	Houston
4	Maricopa	Arizona	23,828.26	9,200.14	3,817,117	4,485,514	668,397	17.51	Phoenix
5	San Diego	California	10,895.12	4,206.63	3,095,313	3,338,330	243,017	7.85	San Diego
6	Orange		2,047.56	790.57	3,010,232	3,175,692	165,460	5.50	Santa Ana
7	Miami-Dade	Florida	4,915.06	1,897.72	2,496,435	2,716,940	220,505	8.83	Miami
8	Dallas	Texas	2,256.60	871.28	2,368,139	2,635,516	267,377	11.29	Dallas
9	Kings	New York	183.41	70.82	2,504,700	2,559,903	55,203	2.20	Brooklyn, NYC
10	Riverside	California	18,664.70	7,206.48	2,189,641	2,470,546	280,905	12.83	Riverside
11	Clark	Nevada	20,438.71	7,891.43	1,951,269	2,266,715	315,446	16.17	Las Vegas
12	Queens	New York	281.10	108.53	2,230,722	2,253,858	23,136	1.04	Queens, NYC
13	King	Washington	5,479.29	2,115.57	1,931,249	2,252,782	321,533	16.65	Seattle
14	San Bernardino	California	51,947.23	20,056.94	2,035,210	2,180,085	144,875	7.12	San Bernardino
15	Tarrant	Texas	2,236.74	863.61	1,809,034	2,102,515	293,481	16.22	Fort Worth
16	Bexar		3,211.12	1,239.82	1,714,773	2,003,554	288,781	16.84	San Antonio
17	Broward	Florida	3,133.33	1,209.79	1,748,066	1,952,778	204,712	11.71	Fort Lauderdale
18	Santa Clara	California	3,341.34	1,290.10	1,781,642	1,927,852	146,210	8.21	San Jose
19	Wayne	Michigan	1,585.28	612.08	1,820,584	1,749,343	-71,241	-3.91	Detroit
20	Alameda	California	1,914.05	739.02	1,510,271	1,671,329	161,058	10.66	Oakland
21	New York	New York	59.13	22.83	1,585,873	1,628,706	42,833	2.70	Manhattan, NYC
22	Middlesex	Massachusetts	2,118.14	817.82	1,503,085	1,611,699	108,614	7.23	Lowell and Cambridge
23	Philadelphia	Pennsylvania	347.32	134.10	1,526,006	1,584,064	58,058	3.80	Philadelphia
24	Sacramento	California	2,498.42	964.64	1,418,788	1,552,058	133,270	9.39	Sacramento
25	Palm Beach	Florida	5,100.00	1,970.00	1,320,134	1,496,770	176,636	13.38	West Palm Beach
26	Suffolk	New York	2,362.20	912.05	1,493,350	1,476,601	-16,749	-1.12	Riverhead
27	Hillsborough	Florida	2,642.34	1,020.21	1,229,226	1,471,968	242,742	19.75	Tampa
28	Bronx	New York	109.03	42.10	1,385,108	1,418,207	33,099	2.39	Bronx, NYC
29	Orange	Florida	2,339.87	903.43	1,145,956	1,393,452	247,496	21.60	Orlando
30	Nassau	New York	737.41	284.72	1,339,532	1,356,924	17,392	1.30	Mineola
31	Franklin	Ohio	1,378.36	532.19	1,163,414	1,316,756	153,342	13.18	Columbus
32	Travis	Texas	2,564.61	990.20	1,024,266	1,273,954	249,688	24.38	Austin
33	Hennepin	Minnesota	1,433.79	553.59	1,152,425	1,265,843	113,418	9.84	Minneapolis
34	Oakland	Michigan	2,247.24	867.66	1,202,362	1,257,584	55,222	4.59	Pontiac
35	Cuyahoga	Ohio	1,184.12	457.19	1,280,122	1,235,072	-45,050	-3.52	Cleveland
36	Allegheny	Pennsylvania	1,890.88	730.07	1,223,348	1,216,045	-7,303	-0.60	Pittsburgh
37	Salt Lake	Utah	1,922.50	742.28	1,029,655	1,160,437	130,782	12.70	Salt Lake City
38	Contra Costa	California	1,854.27	715.94	1,049,025	1,153,526	104,501	9.96	Martinez
39	Fairfax	Virginia	1,012.60	390.97	1,081,726	1,147,532	65,806	6.08	Fairfax
40	Wake	North Carolina	2,163.21	835.22	900,993	1,111,761	210,768	23.39	Raleigh
41	Mecklenburg		1,356.75	523.84	919,628	1,110,356	190,728	20.74	Charlotte
42	Fulton	Georgia	1,363.98	526.63	920,581	1,063,937	143,356	15.57	Atlanta
43	Montgomery	Maryland	1,272.34	491.25	971,777	1,050,688	78,911	8.12	Rockville
44	Pima	Arizona	23,794.31	9,187.04	980,263	1,047,279	67,016	6.84	Tucson
45	Collin	Texas	2,178.76	841.22	782,341	1,034,730	252,389	32.26	McKinney
46	Fresno	California	15,431.13	5,957.99	930,450	999,101	68,651	7.38	Fresno
47	St. Louis	Missouri	1,315.20	507.80	998,954	994,205	-4,749	-0.48	Clayton
48	Pinellas	Florida	709.14	273.80	916,542	974,996	58,454	6.38	Clearwater
49	Honolulu	Hawaii	1,555.92	600.74	953,207	974,563	21,356	2.24	Honolulu
50	Westchester	New York	1,114.98	430.50	949,113	967,506	18,393	1.94	White Plains
51	Marion	Indiana	1,026.41	396.30	903,393	964,582	61,189	6.77	Indianapolis
52	Duval	Florida	1,974.07	762.19	864,263	957,755	93,492	10.82	Jacksonville
53	Milwaukee	Wisconsin	625.23	241.40	947,735	945,726	-2,009	-0.21	Milwaukee
54	Fairfield	Connecticut	1,618.46	624.89	916,829	943,331	26,502	2.89	Bridgeport
55	Shelby	Tennessee	1,976.61	763.17	927,644	937,166	9,522	1.03	Memphis
56	Gwinnett	Georgia	1,114.69	430.38	805,321	936,250	130,929	16.26	Lawrenceville
57	Bergen	New Jersey	603.49	233.01	905,116	932,202	27,086	2.99	Hackensack
58	DuPage	Illinois	848.22	327.50	916,924	922,921	5,997	0.65	Wheaton
59	Erie	New York	2,700.56	1,042.69	919,040	918,702	-338	-0.04	Buffalo
60	Prince George's	Maryland	1,250.16	482.69	863,420	909,327	45,907	5.32	Upper Marlboro
61	Pierce	Washington	4,324.01	1,669.51	795,225	904,980	109,755	13.80	Tacoma
62	Kern	California	21,061.57	8,131.92	839,631	900,202	60,571	7.21	Bakersfield
63	Hartford	Connecticut	1,903.89	735.10	894,014	891,720	-2,294	-0.26	Hartford
64	Denton	Texas	2,275.13	878.43	662,614	887,207	224,593	33.89	Denton
65	San Francisco	California	121.40	46.87	805,235	881,549	76,314	9.48	San Francisco
66	Macomb	Michigan	1,241.18	479.22	840,978	873,972	32,994	3.92	Mount Clemens
67	Hidalgo	Texas	4,068.52	1,570.87	774,769	868,707	93,938	12.12	Edinburg
68	New Haven	Connecticut	1,565.66	604.51	862,477	854,757	-7,720	-0.90	New Haven
69	Ventura	California	4,773.69	1,843.13	823,318	846,006	22,688	2.76	Ventura
70	El Paso	Texas	2,622.86	1,012.69	800,647	839,238	38,591	4.82	El Paso
71	Montgomery	Pennsylvania	1,251.07	483.04	799,874	830,915	31,041	3.88	Norristown
72	Worcester	Massachusetts	3,912.88	1,510.77	798,552	830,622	32,070	4.02	Worcester
73	Baltimore	Maryland	1,549.59	598.30	805,029	827,370	22,341	2.78	Towson
74	Middlesex	New Jersey	800.08	308.91	809,858	825,062	15,204	1.88	New Brunswick
75	Snohomish	Washington	5,406.01	2,087.27	713,335	822,083	108,748	15.25	Everett
76	Hamilton	Ohio	1,051.30	405.91	802,374	817,473	15,099	1.88	Cincinnati
77	Multnomah	Oregon	1,117.05	431.30	735,334	812,855	77,521	10.54	Portland
78	Fort Bend	Texas	2,292	885	585,375	811,688	226,313	38.66	Richmond
79	Suffolk	Massachusetts	150.62	58.15	722,023	803,907	81,884	11.34	Boston
80	Essex	New Jersey	326.89	126.21	783,969	798,975	15,006	1.91	Newark
81	Oklahoma	Oklahoma	1,835.83	708.82	718,633	797,434	78,801	10.97	Oklahoma City
82	Essex	Massachusetts	1,275.73	492.56	743,159	789,034	45,875	6.17	Salem and Lawrence
83	Lee	Florida	2,031.88	784.51	618,754	770,577	151,823	24.54	Fort Myers
84	Jefferson	Kentucky	985.27	380.42	741,096	776,757	35,661	4.81	Louisville
85	San Mateo	California	1,161.37	448.41	718,451	766,573	48,122	6.70	Redwood City
86	San Joaquin	California	3,603.51	1,391.32	685,306	762,148	76,842	11.21	Stockton
87	Cobb	Georgia	879.43	339.55	688,078	760,141	72,063	10.47	Marietta
88	DeKalb		693.03	267.58	691,893	759,257	67,364	9.74	Decatur
89	Monroe	New York	1,702.15	657.21	744,344	741,770	-2,574	-0.35	Rochester
90	Denver	Colorado	401.36	154.97	600,158	727,211	127,053	21.17	Denver
91	Polk	Florida	4,660	1,798	602,095	724,777	122,682	20.38	Bartow
92	El Paso	Colorado	5,508.39	2,126.80	622,263	720,403	98,140	15.77	Colorado Springs
93	Norfolk	Massachusetts	1,025.91	396.11	670,850	706,775	35,925	5.36	Dedham
94	District of Columbia		177.0	68.34	601,723	705,749	104,026	17.29	N/A
95	Jackson	Missouri	1,565.55	604.46	674,158	703,011	28,853	4.28	Independence and Kansas City
96	Lake	Illinois	1,149.10	443.67	703,462	696,535	-6,927	-0.98	Waukegan
97	Davidson	Tennessee	1,305.44	504.03	626,681	694,144	67,463	10.77	Nashville
98	Will	Illinois	2,167.58	836.91	677,560	690,743	13,183	1.95	Joliet
99	Bernalillo	New Mexico	3,006.53	1,160.83	662,564	679,121	16,557	2.50	Albuquerque
100	Hudson	New Jersey	119.63	46.19	634,266	672,391	38,125	6.01	Jersey City

Gallery

• 
  Downtown Los Angeles, county seat of Los Angeles County, California, the most populous county in the United States. County buildings and the civic center, pictured at the bottom right.
• 
  Downtown Chicago, in Cook County, Illinois, the second-most populous county in the United States.
• 
  Downtown Houston, located in Harris County, Texas, the third-most populous county in the United States.
• 
  Downtown Phoenix, Arizona, county seat of the fourth-most populous county in the United States, Maricopa.
• 
  Downtown San Diego, California. San Diego County is the fifth-most populous county in the United States.
• 
  Aerial view of Orange County, California, the sixth-most populous county in the United States.
• 
  Downtown Miami in Miami-Dade County, the largest county in Florida, and the county seat of the seventh-most populous county in the United States.
• 
  Row houses in Brooklyn, Kings County, New York, the ninth-most populous county in the United States.

References

1. "This Is Your City and County of Honolulu Government". City and County of Honolulu. Archived from the original on January 20, 2008. Retrieved January 23, 2008.
2. "City and County Organizational Chart". City and County of San Francisco. Archived from the original on February 3, 2008. Retrieved January 23, 2008.
3. "Active Colorado Municipalities as of January 26, 2010". Colorado Department of Local Affairs. Archived from the original on December 12, 2009. Retrieved January 26, 2010.
4. GeoHive - the United States of America - US States and Counties Archived April 30, 2012, at the Wayback Machine (attached Excel spreadsheet)
5. The area in square kilometers of the column to the left divided by 2.589988110336 (1.609344²).