When was Oneida County founded?

Oneida County was founded in 1864, formed from Boise County and Owyhee County, and named after Oneida Lake, New York.

What is the county seat of Oneida County?

The county seat of Oneida County is Malad City.

Is there an online parcel map for Oneida County?

Yes. Idaho Department of Water Resources publishes a parcel map of 10,670 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Oneida County's boundary or name changed?

Oneida County was created in 1864 from Boise County and Owyhee County. Since then the Atlas of Historical County Boundaries records 11 later changes, chiefly involving Power County, Alturas County and Bannock County.

Is my lot in a flood zone?

We do not have flood maps for Oneida County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

County · code 16071

Oneida CountyIdaho

Oneida County is in Idaho and was created on January 22, 1864, from Boise and Owyhee Counties, with its county seat in Malad City. It was named after Oneida Lake.

Founded1864
County seatMalad City
Named forOneida Lake, New York
Land area1,199 sq mi + 1.5 sq mi water
Population4,564 2020 Census
Parcels mapped10,670 checked 16 October 2026

Open the free map Click any parcel in Oneida County: acreage, parcel id, address and who publishes the map. No sign-in.

Updated 20 October 2026

Census outline · seat marked

History

Formed in 1864 from Boise County and Owyhee County

An old deed may name a county that no longer exists, or a boundary that has since moved.

Oneida County was created by Idaho Territory from Boise and Owyhee Counties on January 22, 1864, initially including territory in present Idaho and most of present Wyoming west of the Rocky Mountains. Over the following decades, the county lost territory to the creation of Dakota Territory in 1864, Wyoming Territory in 1868, and the new counties of Bear Lake in 1875, Cassia in 1879, and Bingham in 1885. Oneida continued as an Idaho county when Idaho became a state and Idaho Territory was eliminated on July 3, 1890.

Boundary changes from the Newberry Library, Atlas of Historical County Boundaries; the 5 that matter most are shown first.

1864
Oneida County created Oneida created by Idaho Territory from Boise and Owyhee; included parts of present Idaho and Wyoming.
from Boise from Owyhee
22 January 1864 · Id. Terr. Laws 1863, loc. and spec., 1st sess., p. 625
1864
Lost territory Oneida lost to Dakota Territory. Oneida continued to include part of present Wyoming. 26 May 1864 · U.S. Stat., vol. 13, ch. 95 [1864], sec. 18/p. 92; Van Zandt, 134-136, 156-157
1868
Lost territory Oneida lost to creation of Wyoming Territory. 25 July 1868 · Trenholm, 1:83-84; U.S. Stat., vol. 15, ch. 235 [1868], secs. 1, 17/pp. 178, 183; Van Zandt, 136, 144, 156
1871
Gained territory Oneida gained from Owyhee.
from Owyhee
2 January 1871 · Id. Terr. Laws 1870, 6th sess., p. 54
1890
Became part of Idaho Oneida continued as an Idaho county when the state of Idaho admitted to the Union and Idaho Territory eliminated. 3 July 1890 · U.S. Stat., vol. 26, ch. 656 [1890]/pp. 215-219; Van Zandt, 156

Show all 13 changes (8 more)

1864
Oneida County created Oneida created by Idaho Territory from Boise and Owyhee; included parts of present Idaho and Wyoming.
from Boise from Owyhee
22 January 1864 · Id. Terr. Laws 1863, loc. and spec., 1st sess., p. 625
1864
Lost territory Oneida lost to Dakota Territory. Oneida continued to include part of present Wyoming. 26 May 1864 · U.S. Stat., vol. 13, ch. 95 [1864], sec. 18/p. 92; Van Zandt, 134-136, 156-157
1868
Lost territory Oneida lost to creation of Wyoming Territory. 25 July 1868 · Trenholm, 1:83-84; U.S. Stat., vol. 15, ch. 235 [1868], secs. 1, 17/pp. 178, 183; Van Zandt, 136, 144, 156
1871
Gained territory Oneida gained from Owyhee.
from Owyhee
2 January 1871 · Id. Terr. Laws 1870, 6th sess., p. 54
1875
Lost territory Oneida lost to creation of Bear Lake.
to Bear Lake
5 January 1875 · Id. Terr. Laws 1874-1875, comp., rev., 8th sess., pp. 720-722
1877
Gained territory Oneida gained from Alturas (extinct) and Lemhi.
from Alturasfrom Lemhi
8 January 1877 · Id. Terr. Laws 1876, 9th sess., pp. 90-91
1879
Lost territory Oneida lost to creation of Cassia.
to Cassia
20 February 1879 · Id. Terr. Laws 1879, 10th sess., pp. 43-46
1885
Lost territory Oneida lost to creation of Bingham.
to Bingham
13 January 1885 · Id. Terr. Laws 1884, 13th sess., pp. 41-43
1887
Boundary clarified Oneida boundaries redefined (no change).
no change
1 June 1887 · Id. Terr. Laws 1887, comp., spec. and loc., 14th sess., p. 191
1890
Became part of Idaho Oneida continued as an Idaho county when the state of Idaho admitted to the Union and Idaho Territory eliminated. 3 July 1890 · U.S. Stat., vol. 26, ch. 656 [1890]/pp. 215-219; Van Zandt, 156
1913
Lost territory Oneida lost to creation of Franklin and Power.
to Franklin to Power
30 January 1913 · Id. Laws 1913, 12th sess., ch. 5/pp. 22-30; ch. 6/pp. 30-45
1916
Lost territory Oneida lost to Power. Act approved 15 March 1915, became effective through a vote in the general election of 7 November 1916.
to Power
7 November 1916 · Id. Laws 1915, 13th sess., ch. 132/pp. 287-289; Id. Code Ann. (1996), vol. 6, ch. 1, sec. 31-139 "Oneida Co."/p. 50
1927
Lost territory Oneida lost to Bannock.
to Bannock
15 March 1927 · Id. Laws 1927, 19th sess., ch. 256/pp. 431-439

Land and parcels

What the maps cover in Oneida

Who publishes each layer, how good it is, and when we last checked.

Parcels Good enough

Lot lines and tax-map numbers for 10,670 parcels from Idaho Department of Water Resources. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 16 October 2026
Address points Missing

No public address points layer found for Oneida County yet.
Buildings Reference

Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026

Official: from the office that keeps the record
Good enough: a reliable statewide or national copy
Fallback: a guide only; check the official record
Missing: nothing public found yet

People and land

Oneida by the Census

Population

4,564 2020 Census count

Housing units

2,009 2020 Census count

Land area

1,199 square miles

Water area

1.5 square miles

People per sq mi

4 population ÷ land area

Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.

Rules and offices

Oneida County's official site

We have found the county's site but not its offices yet; start there.

County government

County government
The official website of Oneida County.
oneidacountyid.com

See your own lot on these maps

Open Oneida County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.

Open the free map no sign-in Pro early access

Questions

Common questions about Oneida County

When was Oneida County founded?: Oneida County was founded in 1864, formed from Boise County and Owyhee County, and named after Oneida Lake, New York.
What is the county seat of Oneida County?: The county seat of Oneida County is Malad City.
Is there an online parcel map for Oneida County?: Yes. Idaho Department of Water Resources publishes a parcel map of 10,670 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Oneida County's boundary or name changed?: Oneida County was created in 1864 from Boise County and Owyhee County. Since then the Atlas of Historical County Boundaries records 11 later changes, chiefly involving Power County, Alturas County and Bannock County.
Is my lot in a flood zone?: We do not have flood maps for Oneida County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby