Idaho

Washington

10,500
2020 population
1880
first census record
15
census records

About Washington

Washington, Idaho, first appears in the United States federal census in 1880, when it recorded a population of 879. At the most recent census, in 2020, its population stood at 10,500.

Its recorded population peaked at 11,101 in 1910, and has since declined by roughly 5 percent.

On the ground today, 31 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
202010,500
201010,198
20009,977
19908,550
19808,803
19707,633
19608,378
19508,576
19408,853
19307,962
19209,424
191011,101
19006,882
18903,836
1880879
Source

Population data from the United States decennial census, U.S. Census Bureau (public domain).

Historic places in Washington

National Register of Historic Places listings in Washington, Idaho.

Anderson-Elwell House
Weiser
Varian, B. S., House
Weiser
Intermountain Institute
Weiser
Washington County Courthouse
Weiser
Sommer, Morris, House
Weiser
Larsen, Archie, House
Weiser
Salubria Lodge No. 31
Cambridge
Cambridge News Office
Cambridge
Knights of Pythias Lodge Hall
Weiser
Browse all Idahohistoric sites ›

Other counties in Idaho

Explore census history and historic records for more Idaho counties.

ShoshoneTetonTwin FallsValleyAdaAdamsAlturasBannockBear LakeBenewahBinghamBlaineBoiseBonnerBonnevilleBoundaryButteCamasCanyonCaribou
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Everything a full report reveals about Washington County, Idaho

This page charts the census history of Washington County, Idaho. A full Aubrey report for an address here pulls together everything the historical record holds about the ground, from the earliest settlement to the twentieth century:

Overview
An interactive map of the location with historic sites, battles and Native heritage plotted, and its full story era by era.
The Land
The historic sites and place names around the location, and how this land was settled and used.
Geology
The bedrock beneath the site, its age and rock type, reaching back millions of years.
LiDAR Terrain
Laser-scanned terrain that reveals earthworks and old features hidden in the landscape.
Conflict & War
The battles, raids and skirmishes fought near here, across every era of American conflict.
The Civil War
The Civil War on this ground, 1861 to 1865: who held it, and the battles, camps and regiments nearby.
The Soldiers
The men who marched from here in the Civil War, named and traced where the record allows.
Native Heritage
The Native nations who held this land, mapped across time from before European contact to today.
Settlement
Who claimed and held this ground, from Indigenous homelands through the colonial powers to the United States.
The Community
How the town grew, who came, and what kind of place it became, traced through the census record.
Rivers & Rail
The rivers, canals and railroads that connected this place between 1830 and 1911.
Notable People
The people born, buried or genuinely tied to this exact place, with their stories.
Historical Maps
Historic maps of the location layered over how it looks today.
Finds & Access
Museum objects tied to the area, and the laws on searching, collecting and access here.
Literature
The old books, county histories and archives that mention this place, quoted with their sources.
Spotlight
A deep dive into the most remarkable, lesser-known history of the place, traced back to the record.
Points of Interest
The most significant historic sites and landmarks near the location, and why they matter.
Timeline
The whole story of the location told era by era, from first peoples to the present day.
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Explore Idaho records

Idahohistory ›NRHP historic sites ›Notable people from Idaho›

Frequently asked about Washington

When does Washington first appear in the US census?
Washington, Idaho first appears in the federal census in 1880, with a recorded population of 879.
What is the population of Washington?
At the most recent federal census (2020), Washington had a recorded population of 10,500.
When did Washington's population peak?
Washington's recorded population peaked at 11,101 in 1910.
How many historic places are in Washington?
31 sites are listed on the National Register of Historic Places in Washington, Idaho.
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