When was Fremont County founded?

Fremont County was founded in 1884, formed from Sweetwater County, and named after John C. Frémont.

What is the county seat of Fremont County?

The county seat of Fremont County is Lander.

Is there an online parcel map for Fremont County?

Yes. Fremont County publishes a parcel map of 21,760 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Fremont County's boundary or name changed?

Fremont County was created in 1884 from Sweetwater County. Since then the Atlas of Historical County Boundaries records 9 later changes, chiefly involving Big Horn County, Hot Springs County and Sublette County.

Is my lot in a flood zone?

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

County · code 56013

Fremont CountyWyoming

Fremont County is in Wyoming and has its county seat in Lander. The county was created on March 5, 1884, from Sweetwater County and named after John C. Frémont.

Founded1884
County seatLander
Named forJohn C. Frémont
Land area9,184 sq mi + 82 sq mi water
Population39,234 2020 Census
Parcels mapped21,760 checked 14 October 2026

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

Updated 20 October 2026

Census outline · seat marked

History

Formed in 1884 from Sweetwater County

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

Fremont County was created by Wyoming Territory from Sweetwater County on March 5, 1884, but was initially attached to Sweetwater for judicial and other purposes until it was fully organized on May 6, 1884. The county lost territory to the creation of Big Horn County in 1890 and to boundary adjustments with Carbon and Natrona in 1909 to align with federal land survey lines. Further territorial losses occurred with the creation of Hot Springs County in 1911 and Sublette County in 1921, with both new counties initially remaining attached to Fremont before full organization.

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

1884
Fremont County created Fremont created by Wyoming Territory from Sweetwater; Fremont not fully organized, attached to Sweetwater "for judicial and all other purposes."
from Sweetwater
5 March 1884 · Wyo. Terr. Laws 1884, 8th leg., ch. 46/pp. 66-69
1890
Lost territory Fremont lost to creation of Big Horn. Big Horn not fully organized, part attached to Fremont "for judicial, revenue and election purposes."
to Big Horn
12 March 1890 · Wyo. Terr. Laws 1890, 11th leg., ch. 48/pp. 80-83
1890
Became part of Wyoming Fremont became a county in the state of Wyoming. 10 July 1890 · Wyoming Constitution 1889, art. 12 in Swindler, 10:493; U.S. Stat., vol. 26, ch. 664[1890]/pp. 222-226; Van Zandt, 145
1909
Lost territory Fremont lost to Carbon and Natrona when boundary was adjusted to run on federal land survey lines.
to Carbon to Natrona
27 February 1909 · Wyo. Laws 1909, 10th leg., ch. 129, secs. 1-3/pp. 174-176
1911
Lost territory Fremont lost to creation of Hot Springs. Hot Springs not fully organized, part attached to Fremont "for judicial, revenue and election purposes." Fremont exchanged territory along former boundary with Uinta when boundary was adjusted to run on federal land survey lines. Technically, Hot Springs had been created on 9 February 1911, but the several boundary laws of February 1911 were not passed in the intended sequence and mapping them in strict chronological order is not practical. By treating the law of 21 February as the basic structure that the other laws modify, the mapping reflects the intent of the legislature.
to Hot Springs to Uinta
21 February 1911 · Wyo. Laws 1911, 11th leg., ch. 9/pp. 9-11 and ch. 77, secs. 6, 13/pp. 106-107, 112-113

Show all 10 changes (5 more)

1884
Fremont County created Fremont created by Wyoming Territory from Sweetwater; Fremont not fully organized, attached to Sweetwater "for judicial and all other purposes."
from Sweetwater
5 March 1884 · Wyo. Terr. Laws 1884, 8th leg., ch. 46/pp. 66-69
1884
Changed Fremont fully organized, detached from Sweetwater.
Sweetwater
6 May 1884 · Trenholm, 1:331
1890
Lost territory Fremont lost to creation of Big Horn. Big Horn not fully organized, part attached to Fremont "for judicial, revenue and election purposes."
to Big Horn
12 March 1890 · Wyo. Terr. Laws 1890, 11th leg., ch. 48/pp. 80-83
1890
Became part of Wyoming Fremont became a county in the state of Wyoming. 10 July 1890 · Wyoming Constitution 1889, art. 12 in Swindler, 10:493; U.S. Stat., vol. 26, ch. 664[1890]/pp. 222-226; Van Zandt, 145
1897
Changed Big Horn fully organized, detached from Fremont.
Big Horn
4 January 1897 · Trenholm, 1:331
1909
Lost territory Fremont lost to Carbon and Natrona when boundary was adjusted to run on federal land survey lines.
to Carbon to Natrona
27 February 1909 · Wyo. Laws 1909, 10th leg., ch. 129, secs. 1-3/pp. 174-176
1911
Lost territory Fremont lost to creation of Hot Springs. Hot Springs not fully organized, part attached to Fremont "for judicial, revenue and election purposes." Fremont exchanged territory along former boundary with Uinta when boundary was adjusted to run on federal land survey lines. Technically, Hot Springs had been created on 9 February 1911, but the several boundary laws of February 1911 were not passed in the intended sequence and mapping them in strict chronological order is not practical. By treating the law of 21 February as the basic structure that the other laws modify, the mapping reflects the intent of the legislature.
to Hot Springs to Uinta
21 February 1911 · Wyo. Laws 1911, 11th leg., ch. 9/pp. 9-11 and ch. 77, secs. 6, 13/pp. 106-107, 112-113
1913
Changed Hot Springs fully organized, detached from Fremont.
Hot Springs
6 January 1913 · Trenholm, 2:518
1921
Lost territory Fremont lost to creation of Sublette. Sublette not fully organized, part attached to Fremont "for judicial, revenue and election purposes."
to Sublette
15 February 1921 · Wyo. Laws 1921, 16th leg., ch. 52/pp. 42-44
1923
Changed Sublette fully organized, detached from Fremont.
Sublette
2 January 1923 · Trenholm, 2:518

Land and parcels

What the maps cover in Fremont

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

Parcels Good enough

Lot lines and tax-map numbers for 21,760 parcels from Fremont County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 14 October 2026
Address points Missing

No public address points layer found for Fremont 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

Fremont by the Census

Population

39,234 2020 Census count

Housing units

17,407 2020 Census count

Land area

9,184 square miles

Water area

82 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

Who to ask before you build, dig or sell

Official county pages only. We link to them; we do not copy them, because they change.

Inside a city or town, permits usually come from that city rather than the county.

Records

Assessor and property records 307-332-1188from fremontcountywy.org · checked 13 October 2026
Clerk of court: deeds and plats 307-332-1063from fremontcountywy.org · checked 13 October 2026

Zoning and code

Planning and zoning 307-335-6961from fremontcountywy.org · checked 13 October 2026

County government

County government
The official website of Fremont County.
fremontcountywy.org

See your own lot on these maps

Open Fremont 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 Fremont County

When was Fremont County founded?: Fremont County was founded in 1884, formed from Sweetwater County, and named after John C. Frémont.
What is the county seat of Fremont County?: The county seat of Fremont County is Lander.
Is there an online parcel map for Fremont County?: Yes. Fremont County publishes a parcel map of 21,760 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Fremont County's boundary or name changed?: Fremont County was created in 1884 from Sweetwater County. Since then the Atlas of Historical County Boundaries records 9 later changes, chiefly involving Big Horn County, Hot Springs County and Sublette County.
Is my lot in a flood zone?: We do not have flood maps for Fremont County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby