When was Trempealeau County founded?

Trempealeau County was founded in 1854, formed from Buffalo County, Chippewa County, Jackson County and La Crosse County, and named after Trempealeau Mountain, Wisconsin and Trempealeau River, Wisconsin.

What is the county seat of Trempealeau County?

The county seat of Trempealeau County is Whitehall.

Is there an online parcel map for Trempealeau County?

Yes. Trempealeau County publishes a parcel map of 33,477 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Trempealeau County's boundary or name changed?

Trempealeau County was created in 1854 from Buffalo County, Chippewa County, Jackson County and La Crosse County. Since then the Atlas of Historical County Boundaries records 2 later changes, chiefly involving La Crosse County.

Is my lot in a flood zone?

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

County · code 55121

Trempealeau CountyWisconsin

Trempealeau County is in Wisconsin with its seat in Whitehall. The county was created on January 27, 1854.

Founded1854
County seatWhitehall
Named forTrempealeau Mountain, Wisconsin and Trempealeau River, Wisconsin
Land area733 sq mi + 9 sq mi water
Population30,760 2020 Census
Parcels mapped33,477 checked 15 October 2026

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

Updated 20 October 2026

Census outline · seat marked

History

Formed in 1854 from Buffalo County, Chippewa County, Jackson County and La Crosse County

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

Trempealeau County was created from Buffalo, Chippewa, Jackson, and La Crosse counties on January 27, 1854, and was initially attached to La Crosse County for judicial purposes. The county was fully organized and detached from La Crosse on January 1, 1855, but was lost to La Crosse again on March 3, 1857. The county is named after Trempealeau Mountain and Trempealeau River.

Boundary changes from the Newberry Library, Atlas of Historical County Boundaries.

1854
Trempealeau County created Trempealeau created from Buffalo, Chippewa, Jackson, and La Crosse; Trempealeau not fully organized, attached to La Crosse "for judicial purposes."
from Buffalo from Chippewa from Jackson from La Crosse
27 January 1854 · Wis. Laws 1854, gen., ch. 2, secs. 1-3, 6, 8/pp. 8-9
1855
Changed Trempealeau fully organized, detached from La Crosse.
La Crosse
1 January 1855 · Wis. Laws 1854, gen., ch. 2, sec. 6/p. 9
1857
Boundary clarified Boundary between Trempealeau and Buffalo was redefined (no change).
with Buffalono change
24 February 1857 · Wis. Laws 1857, gen., ch. 16, secs. 1-2/pp. 21-22
1857
Lost territory Trempealeau lost to La Crosse.
to La Crosse
3 March 1857 · Wis. Laws 1857, gen., ch. 42, secs. 1-2/pp. 43-44

Land and parcels

What the maps cover in Trempealeau

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

Parcels Good enough

Lot lines and tax-map numbers for 33,477 parcels from Trempealeau County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 15 October 2026
Address points Missing

No public address points layer found for Trempealeau 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

Trempealeau by the Census

Population

30,760 2020 Census count

Housing units

13,270 2020 Census count

Land area

733 square miles

Water area

9 square miles

People per sq mi

42 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

Trempealeau 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 Trempealeau County.
tremplocounty.com

See your own lot on these maps

Open Trempealeau 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 Trempealeau County

When was Trempealeau County founded?: Trempealeau County was founded in 1854, formed from Buffalo County, Chippewa County, Jackson County and La Crosse County, and named after Trempealeau Mountain, Wisconsin and Trempealeau River, Wisconsin.
What is the county seat of Trempealeau County?: The county seat of Trempealeau County is Whitehall.
Is there an online parcel map for Trempealeau County?: Yes. Trempealeau County publishes a parcel map of 33,477 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Trempealeau County's boundary or name changed?: Trempealeau County was created in 1854 from Buffalo County, Chippewa County, Jackson County and La Crosse County. Since then the Atlas of Historical County Boundaries records 2 later changes, chiefly involving La Crosse County.
Is my lot in a flood zone?: We do not have flood maps for Trempealeau County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby