• county
  • FIPS 19149
  • Largest town: Le Mars

Plymouth County, Iowa

Plymouth County had 25,825 residents in the Census Vintage 2024 estimate, on 862.8 square miles of land. It ranks 24th of 99 in Iowa by population and 4th by land area.

Population
25,825
#24 of 99 in Iowa · #1,592 in US
Area
862.8 sq mi
#4 of 99 in Iowa · #958 in US
Density
30 / sq mi
#42 of 99 in Iowa · #1,928 in US
Median household income
$74,765
#24 of 99 in Iowa · #681 in US

Census Vintage 2024 estimates · SAIPE 2023 income · 2024 Gazetteer land area

Plymouth County within Iowa. Pin: Des Moines.

Measure from here

Tools and pages that start from Plymouth County

Plymouth County population, land area and income

Plymouth County had 25,825 residents in the Census Vintage 2024 estimate, on 862.8 square miles of land. It ranks 24th of 99 in Iowa by population and 4th by land area. That works out to 29.9 people per square mile, below the US average of 96.3, and below the national county median.

The median county-equivalent in Iowa has 15,008 residents; Plymouth County is somewhat larger.

Its SAIPE 2023 median household income of $74,765 is in the top quarter among 3,143 counties with an estimate.

National rank among 3,144

Population

25,825

3144th1st

1592nd of 3,144 (US)

Land area

863 sq mi

3144th1st

958th of 3,144 (US)

Density

29.9 / sq mi

3144th1st

1928th of 3,144 (US)

Median household income

$74,765

3143rd1st

681st of 3,143 (US)

Rank within Iowa (99)

Population

25,825

99th1st

24th of 99 (IA)

Land area

863 sq mi

99th1st

4th of 99 (IA)

Density

29.9 / sq mi

99th1st

42nd of 99 (IA)

Median household income

$74,765

99th1st

24th of 99 (IA)

How Plymouth County's population changed since 2020

Plymouth County gained 131 residents between the July 2020 and July 2024 estimates, a rise of 0.5%. That ranks 33rd of 99 in Iowa for growth. The median Iowa county changed by -0.6%, and the state as a whole by +1.6%.

Since the April 2020 estimates base, Plymouth County recorded 1,275 births and 1,182 deaths, a natural change of +93. Net international migration added +334 and net domestic migration, people moving to or from other US counties, came to -314. The largest single component was international migration, which added 334 people.

25.7k202025.7k202125.7k202225.8k202325.8k2024
Census Vintage 2024 county estimates for July 1 of each year. The axis starts above zero so year-to-year changes are visible.

Components of change, April 2020 to July 2024

Births
1,275
Deaths
1,182
Net international migration
+334
Net domestic migration
-314
Change, July 2023 to July 2024
+60

Where Plymouth County is

The Census internal point of Plymouth County is at 42.737600, -96.216000. It sits in UTM zone 14N. The map shades Iowa's 99 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Plymouth County outlined. Dots are towns of 1,000+ people with residents in it.

Monroe County: -2.9%Worth County: -1.7%Buena Vista County: +0.0%Jasper County: +0.8%Van Buren County: -0.0%Hardin County: -2.2%Ida County: -3.1%Marshall County: +0.8%Fayette County: -1.5%Ringgold County: -0.8%Wapello County: +1.0%Webster County: -0.2%Adams County: -2.8%Buchanan County: +0.6%Cerro Gordo County: -1.2%Lucas County: +1.6%Emmet County: -1.9%Floyd County: -3.8%Crawford County: -0.7%Linn County: +0.6%Montgomery County: -2.6%Polk County: +4.7%Cherokee County: +0.0%Bremer County: +1.3%Grundy County: +0.5%Adair County: -0.8%Cedar County: -1.4%Story County: +3.9%Mahaska County: -0.6%Davis County: +0.9%Clay County: +0.8%Johnson County: +4.6%Greene County: -1.0%Palo Alto County: -2.0%Benton County: +1.0%Cass County: -0.7%Wright County: -1.5%Audubon County: -2.1%Henry County: -5.3%Boone County: +0.1%Appanoose County: -1.4%Washington County: +0.4%Chickasaw County: -2.2%Poweshiek County: -0.9%Osceola County: -2.6%Wayne County: +1.8%Mitchell County: +0.4%Jefferson County: +0.5%Union County: -1.4%Butler County: -1.2%Hancock County: -1.3%Marion County: +1.9%Delaware County: +0.9%Humboldt County: +0.2%Sioux County: +1.8%Des Moines County: -1.1%O'Brien County: +0.8%Clayton County: -0.6%Black Hawk County: +1.0%Winnebago County: -2.6%Harrison County: +0.4%Decatur County: -1.0%Pocahontas County: -0.9%Lyon County: +3.8%Iowa County: -1.4%Franklin County: +0.3%Dickinson County: +2.2%Madison County: +3.2%Allamakee County: +0.8%Jones County: +2.2%Carroll County: -1.6%Kossuth County: -2.6%Hamilton County: -1.0%Howard County: -1.4%Page County: -1.1%Guthrie County: +1.5%Tama County: -1.8%Monona County: -3.6%Clarke County: -2.1%Lee County: -3.4%Mills County: +2.1%Sac County: -2.7%Scott County: +0.6%Keokuk County: -1.6%Jackson County: -0.3%Warren County: +7.1%Calhoun County: -1.9%Shelby County: +0.8%Fremont County: -1.1%Dubuque County: -0.1%Louisa County: -1.8%Taylor County: -0.6%Woodbury County: +1.2%Clinton County: -0.9%Winneshiek County: -1.6%Pottawattamie County: -0.1%Plymouth County: +0.5%Muscatine County: -2.4%Dallas County: +14.7%
Change 2020 to 2024
  1. < -1.9%
  2. < -1.0%
  3. < +0.0%
  4. < +0.9%
  5. ≥ +0.9%
no data

Orange pin: Plymouth County internal point. Dark pin: Des Moines.

Internal point

Decimal
42.737600, -96.216000
DMS
42°44'15.36"N 96°12'57.60"W
UTM
14N 727889.7E 4735435.3N
Geohash
9zee4s1ss
Plus code
86J5PQQM+2H

Towns in Plymouth County

5 incorporated places of 1,000+ people have residents in Plymouth County, 15,296 people together, or 59% of the county. Each figure counts only the part of the town inside Plymouth County; towns marked "part" extend into another county. The largest is Le Mars with 10,674.

  1. 01Le Mars10,674
  2. 02Remsen1,681
  3. 03Akron1,545
  4. 04Kingsley1,394
  5. 05Sioux City (part)2
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Plymouth County

The Census 2024 county adjacency file lists 5 neighbors for Plymouth County, including 1 across a state line. The most populous is Woodbury County, IA, with 107,257 residents. Distances run between Census internal points in a straight line.

Distance to Des Moines and the nearest big city

Des Moines is 155.5 miles ESE of Plymouth County's internal point in a straight line. The nearest place of 100,000 or more is Sioux Falls, SD (population 209,289), 61.3 miles away. The nearest place of 10,000 or more is Le Mars, IA (population 10,674), 3.7 miles away.

Plymouth County FIPS code

The FIPS code of Plymouth County is 19149: state code 19 for Iowa plus county code 149. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $74,765.

Questions people ask

What is the population of Plymouth County, Iowa?

The Census Vintage 2024 estimate for July 1, 2024 is 25,825. That is up 131 people (0.5%) from the July 2020 estimate of 25,694.

What is the FIPS code of Plymouth County?

19149. The first two digits (19) are Iowa; the last three (149) identify the county.

What is the largest town in Plymouth County?

Le Mars, with 10,674 residents inside Plymouth County in 2024.

Which counties border Plymouth County?

5 county-equivalents border it in the Census 2024 adjacency file: Woodbury County, IA; Sioux County, IA; Union County, SD; O'Brien County, IA; Cherokee County, IA.

Sources and data as of

Data as of: Census Vintage 2024 population estimates, 2024 Gazetteer land area and internal points, SAIPE 2023 median household income.

  1. 01Census Vintage 2024 county population estimates
  2. 02Census 2024 Gazetteer, counties
  3. 03Census SAIPE 2023 state and county estimates
  4. 04Census Vintage 2024 subcounty population estimates
  5. 05Census 2024 county adjacency file
  6. 06Census 2024 cartographic boundary file, counties (1:5,000,000)

How every number is computed: methodology. Spotted a wrong figure? Report an error.