Lewis and Clark County, Montana
Lewis and Clark County: county in Montana, United States
About
Lewis and Clark County is a county located in the U.S. state of Montana. As of the 2010 census, the population was 63,395 and a population density of 7 people per km². After 10 years in 2020 county had an estimated population of 70,229 inhabitants. Its county seat is Helena. The county was created 161 years ago in 1864.
County Snapshot
Lewis and Clark County at a glance
Lewis and Clark County currently has 2 quality-checked populated place pages linked on MapSof, making it easier to jump from the county overview into local city pages.
Mapped populated places
2
These counts use a stricter populated-place filter so the main lists stay focused on real city and town pages.
Montana counties
56
Open related pagesLargest city
HelenaPopulation 33,737
Top linked places
Quick Facts about Lewis and Clark County
| Population | 70,229 (2020) |
| Country | United States of America |
| State | Montana (United States) |
| Different from | Lewis County, Lewis County, Lewis County, Lewis County, Lewis County, Lewis County, Lewis County |
| Area | 9059 km2 |
| Water as percent of area | 1.1% |
| Land as percent of area | 98.9% |
| Latitude & Longitude | 47.1223,-112.3904 |
| Named for | William Clark, Meriwether Lewis |
| Altitude | 5,082 feet / 1549 meters |
| Capital | Helena |
| Establishment | January 01, 1865 |
| Time Zone | America/Denver |
| Local time | 18:35:12 (15th April 2026) |
| Density | 8 Pop. per km² as of 2020 |
| Population growth | 9.73% (2010-2020) |
| Weather | 31℉ Mostly Cloudy then Slight Chance Light Snow 7-days weather |
Geography
Lewis and Clark County is located at 47°7'20"N 112°23'25"W (47.1223400, -112.3903500). It has 7 neighbors: Powell County, Broadwater County, Cascade County, Flathead County, Jefferson County, Meagher County and Teton County.
Lewis and Clark County map
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The largest city of Lewis and Clark County is Helena with a population of 33,737. Other cities include and East Helena population 2,130. See all Lewis and Clark County cities & populated places.
Lewis and Clark County Populated Places
Cities, towns, neighborhoods & other populated places in Lewis and Clark County.
| City Name | Population | Title |
|---|---|---|
| Helena | 33,737 | State capital of Montana, United States and seat of Lewis and Clark County |
| East Helena | 2,130 | Town of the United States |
Weather
A slight chance of snow after midnight. Mostly cloudy, with a low around 31.
7-Day ForecastOfficial website of Lewis and Clark County
Official Website- Helena
Demographics
The population of Lewis and Clark County increased by 9.73% in 10 years.
| Year | Population | % Change | Method |
|---|---|---|---|
| 2010 | 63,395 | - | census |
| 2011 | 64,272 | 1.36% | estimation process |
| 2012 | 64,736 | 0.72% | estimation process |
| 2013 | 65,234 | 0.76% | estimation process |
| 2014 | 65,703 | 0.71% | estimation process |
| 2015 | 66,225 | 0.79% | estimation process |
| 2016 | 66,894 | 1% | estimation process |
| 2017 | 67,850 | 1.41% | estimation process |
| 2018 | 68,622 | 1.13% | estimation process |
| 2019 | 69,432 | 1.17% | estimation process |
| 2020 | 70,229 | 1.13% | estimation process |
People born in Lewis and Clark County (1)
American labor leader W. A. Boyle was born in Lewis and Clark County
Montana Other Counties (more counties)
| County Name | Population | Title |
|---|---|---|
| Yellowstone County | 162,990 | County in Montana, United States of America |
| Missoula County | 121,630 | County in Montana, United States |
| Billings | 117,445 | The most populous city in Montana. |
| Gallatin County | 116,806 | County in Montana, United States |
| Flathead County | 105,851 | County in Montana, United States |
| Cascade County | 81,346 | County in central Montana, United States |
| Missoula | 76,848 | The most populous city in Missoula County, Montana. |
| Great Falls | 58,353 | Town in Cascade County, Montana, United States |
| Bozeman | 50,970 | Town in Gallatin County, Montana, United States |
| Ravalli County | 45,002 | County in Montana, United States |
| Silver Bow County | 35,180 | County in Montana, United States |
| Butte | 34,190 | Consolidated city-county in Montana, United States |
| Helena | 33,737 | State capital of Montana, United States and seat of Lewis and Clark County |
| Lake County | 30,986 | County in Montana, United States |
| Kalispell | 25,329 | City in Flathead County, Montana, United States |
| Lincoln County | 20,343 | County in Montana, United States |