The map above shows Idaho and New Mexico side by side at exactly the same scale, using equal-area projections, so their true relative sizes are preserved.
Idaho vs New Mexico Geography
Land area: Idaho has a land area of 82,645 square miles (214,051 km²), while New Mexico has 121,313 square miles (314,198 km²). New Mexico's land area is 1.5 times (47%) larger than Idaho's.
Total area: Idaho: 83,569 square miles (216,441 km²) vs New Mexico: 121,593 square miles (314,925 km²), including inland and coastal water. New Mexico's total area is 1.5 times (46%) larger than Idaho's.
Length: Idaho is 483 miles (778 km) long from north to south; New Mexico is 395 miles (635 km). Idaho's north-south length is 1.2 times (22%) longer than New Mexico's.
Width: Idaho spans 352 miles (566 km) east to west; New Mexico spans 498 miles (801 km). New Mexico's east-west width is 1.4 times (41%) wider than Idaho's.
Highest point: Idaho's highest point is Borah Peak at 12,631 feet (3,850 m); New Mexico's is Wheeler Peak at 13,150 feet (4,008 m). Wheeler Peak is 519 feet higher than Borah Peak.
Lowest point: Idaho's lowest point is Snake River at 718 feet; New Mexico's is Red Bluff Reservoir at 2,842 feet. Idaho's lowest point is 2,124 feet lower.
Idaho vs New Mexico Population and History
Population: Idaho has a population of 2,001,619 (2024), while New Mexico has 2,130,256 (2024). New Mexico's population is 1.1 times (6%) larger than Idaho's.
Population density: Idaho: 24.2 people per square mile vs New Mexico: 17.6. Idaho's population density is 1.4 times (38%) higher than New Mexico's.
Biggest city: Idaho's biggest city is Boise with 237,963 people; New Mexico's is Albuquerque with 560,326. Albuquerque's population is 2.4 times (135%) larger than Boise's.
Largest metro area: Idaho's largest metropolitan area is Boise City, ID metro area (845,877 people) vs New Mexico's Albuquerque, NM metro area (926,303). Albuquerque, NM metro area's population is 1.1 times (10%) larger than Boise City, ID metro area's.
History: Idaho: Admitted to the Union on July 3, 1890, as the 43rd state. New Mexico: Admitted to the Union on January 6, 1912, as the 47th state. In its current form, Idaho is the older of the two by 22 years.
Idaho vs New Mexico Economy
GDP: Idaho's GDP is $129.0 billion (2024) vs New Mexico's $147.1 billion. New Mexico's economic output is 1.1 times (14%) larger than Idaho's.
GDP per capita: Idaho: $64,457 per person vs New Mexico: $69,046. New Mexico's GDP per capita is 1.1 times (7%) higher than Idaho's.
Average income: Idaho: $62,323 vs New Mexico: $58,249 average income per person (per capita personal income). Idaho's average income is 1.1 times (7%) higher than New Mexico's.
Idaho vs New Mexico Counties
Number of counties: Idaho has 44 counties, while New Mexico has 33. Idaho's county count is 1.3 times (33%) higher than New Mexico's.
Biggest county by area: Idaho's largest county is Idaho County at 8,478 square miles; New Mexico's is Catron County at 6,924 square miles. Idaho County's land area is 1.2 times (22%) larger than Catron County's.
Smallest county by area: Idaho: Payette County (407 sq mi) vs New Mexico: Los Alamos County (109 sq mi). Payette County's land area is 3.7 times (273%) larger than Los Alamos County's.
Most populous county: Idaho: Ada County (535,799 people) vs New Mexico: Bernalillo County (671,747 people). Bernalillo County's population is 1.3 times (25%) larger than Ada County's.
Least populous county: Idaho: Clark County (794 people) vs New Mexico: Harding County (635 people). Clark County's population is 1.3 times (25%) larger than Harding County's.
Richest county: Idaho: Blaine County ($202,612 per capita income) vs New Mexico: Los Alamos County ($98,378). Blaine County's income is 2.1 times (106%) richer than Los Alamos County's.
Poorest county: Idaho: Madison County ($29,485 per capita income) vs New Mexico: Cibola County ($36,397). Cibola County's income is 1.2 times (23%) richer than Madison County's.
Idaho vs New Mexico Taxes
State income tax: Idaho has a top income tax rate of 5.3%, while New Mexico has a top income tax rate of 5.9%. New Mexico's top rate is 0.6 percentage points higher.
Property tax: Idaho: 0.43% effective rate vs New Mexico: 0.63% of home value per year. New Mexico's rate is 0.2 percentage points higher.
Sales tax: Idaho: 6.03% combined state and average local rate vs New Mexico: 7.68%. New Mexico's combined rate is 1.65 percentage points higher.
Official Websites
Idaho official website · New Mexico official website
More Size Comparisons
All Idaho size comparisons · All New Mexico size comparisons
Area, elevation and boundary figures come from official national statistics and US Census Bureau and Natural Earth boundary data; US state population, economic, county and tax figures come from the US Census Bureau, the Bureau of Economic Analysis and the Tax Foundation. Figures are rounded and for general reference.