Bordering states

Idaho vs Utah

Short answer

Utah has 3,503,613 residents, 75% more than Idaho's 2,001,619. Idaho is the larger by land, 1.00 times the size of Utah.
ID
2,001,619
UT
3,503,613

The two states, county by county

Both maps share one density scale, so the same shade means the same number of people per square mile on either side of the border. Darker counties are denser. Select a county to open its page.

Idaho

Madison County: 118.4 per sq miIdaho County: 2.1 per sq miBenewah County: 13.6 per sq miGooding County: 22.2 per sq miLincoln County: 4.6 per sq miMinidoka County: 30.0 per sq miCuster County: 0.9 per sq miBoundary County: 11.1 per sq miLemhi County: 1.8 per sq miTwin Falls County: 50.2 per sq miFranklin County: 23.6 per sq miOneida County: 4.2 per sq miGem County: 39.0 per sq miShoshone County: 5.3 per sq miFremont County: 7.7 per sq miClearwater County: 3.7 per sq miKootenai County: 152.1 per sq miCassia County: 10.1 per sq miBlaine County: 9.6 per sq miClark County: 0.5 per sq miJerome County: 43.6 per sq miBonner County: 31.1 per sq miElmore County: 9.7 per sq miCaribou County: 4.1 per sq miBonneville County: 71.6 per sq miJefferson County: 31.9 per sq miPower County: 6.0 per sq miLewis County: 7.8 per sq miNez Perce County: 50.5 per sq miAda County: 509.2 per sq miAdams County: 3.7 per sq miValley County: 3.5 per sq miBingham County: 24.3 per sq miBannock County: 81.8 per sq miOwyhee County: 1.7 per sq miWashington County: 7.9 per sq miLatah County: 39.2 per sq miTeton County: 28.8 per sq miCamas County: 1.2 per sq miBoise County: 4.5 per sq miBear Lake County: 6.9 per sq miButte County: 1.2 per sq miCanyon County: 454.6 per sq miPayette County: 68.0 per sq mi

Utah

Iron County: 20.0 per sq miRich County: 2.7 per sq miSummit County: 23.0 per sq miSan Juan County: 1.9 per sq miDuchesne County: 6.4 per sq miUintah County: 8.5 per sq miGrand County: 2.7 per sq miBox Elder County: 11.1 per sq miCache County: 124.9 per sq miGarfield County: 1.0 per sq miSalt Lake County: 1,615.6 per sq miUtah County: 372.8 per sq miSanpete County: 19.3 per sq miWayne County: 1.1 per sq miPiute County: 2.0 per sq miEmery County: 2.3 per sq miJuab County: 3.9 per sq miSevier County: 11.8 per sq miWasatch County: 32.2 per sq miDaggett County: 1.4 per sq miKane County: 2.1 per sq miTooele County: 12.0 per sq miMorgan County: 21.5 per sq miWeber County: 451.9 per sq miDavis County: 1,165.4 per sq miWashington County: 85.7 per sq miBeaver County: 2.9 per sq miMillard County: 2.0 per sq miCarbon County: 13.9 per sq mi
People per sq mi
  1. < 2
  2. < 6
  3. < 19
  4. < 44
  5. ≥ 44
no data

Residents, 2024

  1. 01Idaho2,001,619
  2. 02Utah3,503,613

Land, square miles

  1. 01Idaho82,645
  2. 02Utah82,596

People per square mile

  1. 01Idaho24.2
  2. 02Utah42.4

Median county household income

  1. 01Idaho$67,254
  2. 02Utah$75,024

Side by side

MeasureIdahoUtah
Residents, 20242,001,6193,503,613
Rank by population38th30th
Land, sq mi82,64582,596
People per sq mi24.242.4
County-equivalents4429
Median county residents15,01920,803
Median county income$67,254$75,024
Most populous countyAda CountySalt Lake County
Largest county by landIdaho CountySan Juan County
CapitalBoiseSalt Lake City
Daylight at capital, June 2115 h 26 min15 h 06 min
Census divisionMountainMountain
Census Vintage 2024 population, 2024 Gazetteer land area, SAIPE 2023 income. Daylight computed with SunCalc.

Population and density

Utah has 3,503,613 residents, 75% more than Idaho's 2,001,619. Idaho ranks 38th and Utah 30th of the 50 states and DC. Utah is the more crowded, with 42.4 people per square mile against 24.2, 75% more.

Land area

Idaho has 82,645 square miles of land, about the same as Utah's 82,596. The largest county-equivalent in Idaho is Idaho County at 8,478 square miles; in Utah it is San Juan County at 7,824.

Counties

Idaho is divided into 44 county-equivalents and Utah into 29, so an average Idaho county covers 1,878 square miles against 2,848. The typical county in Idaho has 15,019 residents, against 20,803 in Utah. The most populous are Ada County (535,799) and Salt Lake County (1,216,274).

1 county name appears on both sides of the border: Washington. Use the FIPS code, not the name, when joining data across the two states.

Household income

The median county in Utah has a household income of $75,024, 12% above Idaho's $67,254. The highest county incomes are Teton County ($94,895) in Idaho and Summit County ($139,848) in Utah, from SAIPE 2023.

Capitals and daylight

Boise and Salt Lake City are 296 miles apart in a straight line; from Boise the initial bearing is 130°, SE. On June 21, 2026, Boise gets 15 h 26 min of daylight and Salt Lake City 15 h 06 min; on December 21 the figures are 8 h 56 min and 9 h 15 min. Month by month tables are on the Boise and Salt Lake City daylight pages.

Where they sit

Both are in the Census Mountain division of the West region. By county internal points, Idaho spans 2 UTM zones and Utah 1.

Questions people ask

Which is bigger, Idaho or Utah?

Idaho, with 82,645 square miles of land against 82,596, 1.00 times as large.

Which has more people, Idaho or Utah?

Utah has 3,503,613 residents, 75% more than Idaho's 2,001,619.

How far is Boise from Salt Lake City?

296 miles in a straight line, heading SE (130°) from Boise.

Do Idaho and Utah have counties with the same name?

Yes, 1: Washington.

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 Bureau regions and divisions of the United States (last verified 2026-09-30)

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