• county
  • FIPS 30111
  • Largest town: Billings

Yellowstone County, Montana

Yellowstone County had 171,583 residents in the Census Vintage 2024 estimate, on 2,633.4 square miles of land. It is the most populous of Montana's 56 county-equivalents.

Population
171,583
#1 of 56 in Montana · #407 in US
Area
2,633.4 sq mi
#23 of 56 in Montana · #202 in US
Density
65 / sq mi
#1 of 56 in Montana · #1,235 in US
Median household income
$70,221
#13 of 56 in Montana · #985 in US

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

Yellowstone County within Montana. Pin: Helena.

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Yellowstone County population, land area and income

Yellowstone County had 171,583 residents in the Census Vintage 2024 estimate, on 2,633.4 square miles of land. It is the most populous of Montana's 56 county-equivalents. That works out to 65.2 people per square mile, below the US average of 96.3, and above the national county median.

The median county-equivalent in Montana has 7,814 residents, so Yellowstone County is 22.0 times that size.

Its SAIPE 2023 median household income of $70,221 is above the national county median among 3,143 counties with an estimate.

National rank among 3,144

Population

171,583

3144th1st

407th of 3,144 (US)

Land area

2,633 sq mi

3144th1st

202nd of 3,144 (US)

Density

65.2 / sq mi

3144th1st

1235th of 3,144 (US)

Median household income

$70,221

3143rd1st

985th of 3,143 (US)

Rank within Montana (56)

Population

171,583

56th1st

1st of 56 (MT)

Land area

2,633 sq mi

56th1st

23rd of 56 (MT)

Density

65.2 / sq mi

56th1st

1st of 56 (MT)

Median household income

$70,221

56th1st

13th of 56 (MT)

How Yellowstone County's population changed since 2020

Yellowstone County gained 6,373 residents between the July 2020 and July 2024 estimates, a rise of 3.9%. That ranks 23rd of 56 in Montana for growth. The median Montana county changed by +2.8%, and the state as a whole by +4.6%.

Since the April 2020 estimates base, Yellowstone County recorded 7,803 births and 7,552 deaths, a natural change of +251. Net international migration added +335 and net domestic migration, people moving to or from other US counties, came to +6,212. The largest single component was domestic migration, which added 6,212 people.

165.2k2020167.4k2021169.8k2022170.7k2023171.6k2024
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
7,803
Deaths
7,552
Net international migration
+335
Net domestic migration
+6,212
Change, July 2023 to July 2024
+856

Where Yellowstone County is

The Census internal point of Yellowstone County is at 45.937000, -108.276700. It sits in UTM zone 12N. The map shades Montana's 56 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Yellowstone County outlined. Dots are towns of 1,000+ people with residents in it.

Liberty County: -1.2%Golden Valley County: +5.1%Dawson County: -2.1%Flathead County: +9.2%Beaverhead County: +6.7%Prairie County: +2.0%Garfield County: +0.9%Lewis and Clark County: +5.5%Sweet Grass County: +2.4%Wheatland County: -0.7%Ravalli County: +8.5%Jefferson County: +9.6%Carter County: -0.6%Chouteau County: -0.6%Custer County: +0.9%Teton County: +3.1%Granite County: +9.0%Deer Lodge County: +4.1%Cascade County: +0.1%Powder River County: +2.4%Meagher County: +7.3%Daniels County: -1.7%Glacier County: -1.8%Wibaux County: -2.7%Fallon County: -2.7%McCone County: -0.7%Sheridan County: -2.5%Missoula County: +3.5%Toole County: +3.7%Sanders County: +11.5%Roosevelt County: -5.6%Rosebud County: -1.3%Treasure County: -2.5%Yellowstone County: +3.9%Blaine County: -1.4%Musselshell County: +14.8%Broadwater County: +21.0%Powell County: +2.6%Fergus County: +3.4%Phillips County: +0.1%Gallatin County: +6.2%Silver Bow County: +2.6%Madison County: +12.6%Richland County: -4.4%Lake County: +6.9%Valley County: -1.7%Judith Basin County: +4.3%Hill County: -1.2%Big Horn County: -2.2%Stillwater County: +5.0%Carbon County: +9.4%Mineral County: +13.7%Petroleum County: +4.6%Pondera County: +3.4%Park County: +4.9%Lincoln County: +12.4%
Change 2020 to 2024
  1. < -1.4%
  2. < +0.9%
  3. < +3.9%
  4. < +7.3%
  5. ≥ +7.3%
no data

Orange pin: Yellowstone County internal point. Dark pin: Helena.

Internal point

Decimal
45.937000, -108.276700
DMS
45°56'13.20"N 108°16'36.12"W
UTM
12N 711108.1E 5090654.3N
Geohash
c85j24e66
Plus code
85QHWPPF+R8

Towns in Yellowstone County

2 incorporated places of 1,000+ people have residents in Yellowstone County, 128,734 people together, or 75% of the county. Each figure counts only the part of the town inside Yellowstone County; towns marked "part" extend into another county. The largest is Billings with 121,483.

  1. 01Billings121,483
  2. 02Laurel7,251
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Yellowstone County

The Census 2024 county adjacency file lists 7 neighbors for Yellowstone County. The most populous is Big Horn County, MT, with 12,796 residents. Distances run between Census internal points in a straight line.

Distance to Helena and the nearest big city

Helena is 184.2 miles WNW of Yellowstone County's internal point in a straight line. The nearest place of 100,000 or more is Billings, MT (population 121,483), 16.8 miles away.

Yellowstone County FIPS code

The FIPS code of Yellowstone County is 30111: state code 30 for Montana plus county code 111. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $70,221.

Questions people ask

What is the population of Yellowstone County, Montana?

The Census Vintage 2024 estimate for July 1, 2024 is 171,583. That is up 6,373 people (3.9%) from the July 2020 estimate of 165,210.

What is the FIPS code of Yellowstone County?

30111. The first two digits (30) are Montana; the last three (111) identify the county.

What is the largest town in Yellowstone County?

Billings, with 121,483 residents inside Yellowstone County in 2024.

Which counties border Yellowstone County?

7 county-equivalents border it in the Census 2024 adjacency file: Big Horn County, MT; Carbon County, MT; Stillwater County, MT; Rosebud County, MT; Musselshell County, MT; Golden Valley County, MT; Treasure County, MT.

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.