Idaho population

Organization

U.S. Census Bureau

Dataset

Population Estimates Program, Vintage 2025 (with Vintage 2019 for 2010-2019)

Geography

Nation, states, counties, and the ten largest Idaho incorporated places

Time coverage

2010-2025

Update frequency

Annual

Published

May 14, 2026

Retrieved

September 8, 2026

Original file

https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/counties/totals/co-est2025-alldata.csv

Methodology

https://www.census.gov/programs-surveys/popest/technical-documentation/methodology.html

License

Public domain. U.S. federal government work.

Our copy

census-pep, built by scripts/fetch-census-pep.py

Caveats

• Population totals for 2010-2019 are the Vintage 2019 intercensal series (nst-est2019-alldata.csv and co-est2019-alldata.csv), the Census Bureau's final pre-2020-Census estimates, released 2019-12-30 (states/nation) and 2020-03-26 (counties). Totals for 2020-2025 are the Vintage 2025 series (NST-EST2025-ALLDATA.csv and co-est2025-alldata.csv), released 2026-01-27 (states/nation) and 2026-03-26 (counties). The two series are built independently around the 2010 and 2020 Censuses respectively and are not reconciled to each other, so a value for 2019 and a value for 2020 at the same geography can show an implausible jump or drop that is a seam between series, not real population change.
• City (incorporated place) totals cover 2020-2025 only, from the Vintage 2025 sub-county file (sub-est2025_16.csv), released 2026-05-14; no 2010-2019 city series is included.
• Components of change (births, deaths, natural change, domestic migration, international migration, net migration) are published only for the nation, Idaho, and Idaho's 44 counties, not for the other 49 states, matching what this site pulls.
• The component period for estimate year Y normally runs from July 1 of year Y-1 to June 30 of year Y. The single exception is 2020: its components run from April 1, 2020 (Census Day) to June 30, 2020, a 3-month stub, because it is the first estimate after the 2020 Census; every 2020 component observation carries a note saying so.
• 2010-2019 files label the births-minus-deaths column NATURALINC; 2020-2025 files label it NATURALCHG. Both are mapped to metric population.natural_change; the underlying definition (births minus deaths over the period) is unchanged.
• The ten largest Idaho places are Boise City, Meridian, Nampa, Caldwell, Idaho Falls, Pocatello, Coeur d'Alene, Twin Falls, Post Falls and Rexburg, ranked by each place's own 2025 Vintage 2025 estimate; their place FIPS codes were read directly from sub-est2025_16.csv, not assumed.
• Group quarters estimates, the RESIDUAL column, and the published birth/death/migration rates (per 1,000 population) are not pulled.
• Puerto Rico, which appears in the national/state files as SUMLEV 040 STATE 72, is skipped because it is not in data/geographies.json.

Where sources disagree

• population.total, 16, 2020: 2020 Census apportionment counts (census-decennial dataset, apportionment.csv) publishes 1839106. The Vintage 2025 Population Estimates Program's April 1, 2020 base for Idaho (ESTIMATESBASE2020) is 1,839,123, 17 more than the 1,839,106 the Census Bureau delivered as Idaho's official 2020 Census apportionment count. This estimates-base figure is not itself shipped as an observation (it is not a July 1 estimate), but the same small, unreconciled gap likely carries into this dataset's 2020-2025 state and county totals, which build forward from that base.