The U.S. State of Iowa currently has 31 statistical areas that have been delineated by the Office of Management and Budget (OMB). On July 21, 2023, the OMB delineated seven combined statistical areas , nine metropolitan statistical areas , and 15 micropolitan statistical areas in Iowa.[ 1] As of 2023, the largest of these is the Des Moines-West Des Moines-Ames, IA CSA , comprising the area around Iowa's capital and largest city, Des Moines .
The Office of Management and Budget (OMB) has designated more than 1,000 statistical areas for the United States and Puerto Rico .[ 2] These statistical areas are important geographic delineations of population clusters used by the OMB, the United States Census Bureau , planning organizations, and federal, state, and local government entities.
The OMB defines a core-based statistical area (commonly referred to as a CBSA ) as the county or counties (or county-equivalents ) surrounding at least one densely-settled core of at least 10,000 population,[ 2] "plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core".[ 2] The OMB further divides core-based statistical areas based on population into metropolitan statistical areas (MSAs) for those with at least 50,000 and micropolitan statistical areas (μSAs) for those with 10,000 to 49,999 people.[ 2]
The OMB defines a combined statistical area (CSA) as two or more adjacent core-based statistical areas where the employment interchange rate (% commuting from A to B plus % commuting from B to A) is at least 15%.[ 2] The primary statistical areas (PSAs) include all combined statistical areas and any core-based statistical area that is not a constituent of a combined statistical area.
The 31 United States statistical areas and 99 counties of the State of Iowa [ a]
Combined statistical area[ 1]
2023 population (est.)[ 3]
Core-based statistical area[ 1]
2023 population (est.)[ 3]
County
2023 population (est.)[ 3]
Des Moines-West Des Moines-Ames, IA CSA
917,964
Des Moines-West Des Moines, IA MSA
737,164
Polk County, Iowa
505,255
Dallas County, Iowa
111,092
Warren County, Iowa
55,205
Jasper County, Iowa
37,919
Madison County, Iowa
16,971
Guthrie County, Iowa
10,722
Ames, IA MSA
125,156
Story County, Iowa
98,566
Boone County, Iowa
26,590
Pella, IA μSA
33,770
Marion County, Iowa
33,770
Oskaloosa, IA μSA
21,874
Mahaska County, Iowa
21,874
Cedar Rapids-Iowa City, IA CSA
455,756
Cedar Rapids, IA MSA
275,668
Linn County, Iowa
228,972
Benton County, Iowa
25,796
Jones County, Iowa
20,900
Iowa City, IA MSA
180,088
Johnson County, Iowa
157,528
Washington County, Iowa
22,560
Davenport-Moline, IA-IL CSA
467,817 262,646 (IA )
Davenport-Moline-Rock Island, IA-IL MSA
379,441 174,270 (IA)
Scott County, Iowa
174,270
Rock Island County, Illinois
141,236
Henry County, Illinois
48,448
Mercer County, Illinois
15,487
Clinton, IA μSA
46,158
Clinton County, Iowa
46,158
Muscatine, IA μSA
42,218
Muscatine County, Iowa
42,218
none
Waterloo-Cedar Falls, IA MSA
168,162
Black Hawk County, Iowa
130,471
Bremer County, Iowa
25,307
Grundy County, Iowa
12,384
Sioux City-Le Mars, IA-NE-SD CSA
170,124 131,673 (IA)
Sioux City, IA-NE-SD MSA
144,402 105,951 (IA)
Woodbury County, Iowa
105,951
Dakota County, Nebraska
21,268
Union County, South Dakota
17,183
Le Mars, IA μSA
25,722
Plymouth County, Iowa
25,722
Omaha-Fremont, NE-IA CSA
1,021,156 122,482 (IA)
Omaha, NE-IA MSA
983,969 122,482 (IA)
Douglas County, Nebraska
589,540
Sarpy County, Nebraska
199,886
Pottawattamie County, Iowa
93,179
Cass County, Nebraska
27,446
Saunders County, Nebraska
23,463
Washington County, Nebraska
21,152
Harrison County, Iowa
14,670
Mills County, Iowa
14,633
Fremont, NE μSA
37,187
Dodge County, Nebraska
37,187
none
Dubuque, IA MSA
98,887
Dubuque County, Iowa
98,887
Burlington-Fort Madison, IA-IL CSA
76,906 70,818 (IA)
Burlington, IA-IL μSA
44,341 38,253 (IA)
Des Moines County, Iowa
38,253
Henderson County, Illinois
6,088
Fort Madison, IA μSA
32,565
Lee County, Iowa
32,565
none
Mason City, IA μSA
49,703
Cerro Gordo County, Iowa
42,406
Worth County, Iowa
7,297
Marshalltown, IA μSA
40,014
Marshall County, Iowa
40,014
Fort Dodge, IA μSA
36,485
Webster County, Iowa
36,485
Ottumwa, IA μSA
35,166
Wapello County, Iowa
35,166
Spencer-Spirit Lake, IA CSA
34,567
Spirit Lake, IA μSA
18,056
Dickinson County, Iowa
18,056
Spencer, IA μSA
16,511
Clay County, Iowa
16,511
none
Storm Lake, IA μSA
20,567
Buena Vista County, Iowa
20,567
Carroll, IA μSA
20,522
Carroll County, Iowa
20,522
none
Sioux County, Iowa
36,246
Buchanan County, Iowa
20,691
Winneshiek County, Iowa
19,815
Henry County, Iowa
19,547
Jackson County, Iowa
19,342
Fayette County, Iowa
19,210
Poweshiek County, Iowa
18,453
Cedar County, Iowa
18,302
Delaware County, Iowa
17,600
Clayton County, Iowa
16,969
Tama County, Iowa
16,833
Hardin County, Iowa
16,463
Iowa County, Iowa
16,381
Crawford County, Iowa
16,013
Jefferson County, Iowa
15,440
Floyd County, Iowa
15,326
Page County, Iowa
15,014
Hamilton County, Iowa
14,729
Kossuth County, Iowa
14,396
Butler County, Iowa
14,172
Allamakee County, Iowa
14,074
O'Brien County, Iowa
14,012
Cass County, Iowa
13,130
Wright County, Iowa
12,656
Lyon County, Iowa
12,324
Appanoose County, Iowa
12,119
Union County, Iowa
11,906
Shelby County, Iowa
11,806
Chickasaw County, Iowa
11,658
Cherokee County, Iowa
11,605
Hancock County, Iowa
10,615
Winnebago County, Iowa
10,571
Mitchell County, Iowa
10,518
Louisa County, Iowa
10,513
Montgomery County, Iowa
10,139
Keokuk County, Iowa
9,914
Franklin County, Iowa
9,875
Calhoun County, Iowa
9,763
Sac County, Iowa
9,686
Clarke County, Iowa
9,588
Humboldt County, Iowa
9,500
Howard County, Iowa
9,376
Emmet County, Iowa
9,229
Davis County, Iowa
9,169
Palo Alto County, Iowa
8,810
Lucas County, Iowa
8,747
Greene County, Iowa
8,584
Monona County, Iowa
8,493
Decatur County, Iowa
7,665
Monroe County, Iowa
7,504
Adair County, Iowa
7,389
Van Buren County, Iowa
7,266
Pocahontas County, Iowa
6,976
Ida County, Iowa
6,833
Wayne County, Iowa
6,557
Fremont County, Iowa
6,458
Osceola County, Iowa
5,978
Taylor County, Iowa
5,924
Audubon County, Iowa
5,534
Ringgold County, Iowa
4,642
Adams County, Iowa
3,544
State of Iowa
3,207,004
Primary statistical areas [ edit ]
Primary statistical areas (PSAs) include all combined statistical areas and any core-based statistical area that is not a constituent of a combined statistical area. Of the 31 statistical areas of Iowa, 15 are PSAs comprising seven combined statistical areas, two metropolitan statistical areas and six micropolitan statistical areas.
The 15 primary statistical areas of the State of Iowa[ b]
2020 rank
Primary statistical area [ 1]
Population
2023 estimate[ 3]
Change
2020 Census [ 4]
Change
2010 Census [ 5]
1
Des Moines-West Des Moines-Ames, IA CSA
917,964
+3.10 %
890,322
+14.44 %
778,013
2
Cedar Rapids-Iowa City, IA CSA
455,756
+0.84 %
451,939
+10.09 %
410,526
3
Davenport-Moline, IA-IL CSA (IA)
262,646
−0.65 %
264,364
+2.83 %
257,085
4
Waterloo-Cedar Falls, IA MSA
168,162
−0.18 %
168,461
+0.38 %
167,819
5
Sioux City-Le Mars, IA-NE-SD CSA (IA)
131,673
+0.03 %
131,639
+3.52 %
127,158
6
Omaha-Fremont, NE-IA CSA (IA)
122,482
−0.20 %
122,733
−0.33 %
123,145
7
Dubuque, IA MSA
98,887
−0.38 %
99,266
+5.99 %
93,653
8
Burlington-Fort Madison, IA-IL CSA (IA)
70,818
−2.27 %
72,465
−4.89 %
76,187
9
Mason City, IA μSA
49,703
−1.71 %
50,570
−2.28 %
51,749
10
Marshall, IA μSA
40,014
−0.23 %
40,105
−1.34 %
40,648
11
Fort Dodge, IA μSA
36,485
−1.39 %
36,999
−2.67 %
38,013
12
Ottumwa, IA μSA
35,166
−0.76 %
35,437
−0.53 %
35,625
13
Spencer-Spirit Lake, IA CSA
34,567
+1.41 %
34,087
+2.26 %
33,334
14
Storm Lake, IA μSA
20,567
−1.23 %
20,823
+2.78 %
20,260
15
Carroll, IA μSA
20,522
−1.15 %
20,760
−0.27 %
20,816
Davenport-Moline, IA-IL CSA
467,817
−1.31 %
474,019
+0.74 %
470,527
Sioux City-Le Mars, IA-NE-SD CSA
170,124
+0.05 %
170,032
+4.59 %
162,563
Omaha-Fremont, NE-IA CSA
1,021,156
+1.63 %
1,004,771
+11.39 %
902,041
Burlington-Fort Madison, IA-IL CSA
76,906
−2.47 %
78,852
−5.59 %
83,518
^ An out-of-state area and its population are displayed in green. An area that extends into more than one state is displayed in purple. A purple population number over a black population number show the total population versus the in-state population.
^ For PSAs comprising populations from multiple states, they are listed twice to show both their intrastate population within that PSA as well as the PSA's total population. Only the intrastate population is ranked.
^ a b c d Revised Delineations of Metropolitan Statistical Areas, Micropolitan Statistical Areas, and Combined Statistical Areas, and Guidance on Uses of the Delineations of These Areas (July 21, 2023). "0MB BULLETIN NO. 23-01" (PDF) . Office of Management and Budget . Retrieved October 23, 2023 . {{cite web }}
: CS1 maint: multiple names: authors list (link )
^ a b c d e "2020 Standards for Delineating Core Based Statistical Areas" . Office of Management and Budget . July 16, 2021. Retrieved December 13, 2021 .
^ a b c d "County Population Totals and Components of Change: 2020-2023" . United States Census Bureau , Population Division. March 2023. Retrieved May 21, 2024 .
^ "PROFILE OF GENERAL POPULATION AND HOUSING CHARACTERISTICS" . U.S. Census Bureau . 2020. Retrieved May 21, 2024 .
^ "Annual Estimates of the Resident Population for Counties: April 1, 2010 to July 1, 2019" . U.S. Census Bureau . 2019. Retrieved May 21, 2024 .
42°04′30″N 93°29′46″W / 42.0751°N 93.4960°W / 42.0751; -93.4960 (State of Iowa )