When was Deer Lodge County founded?

Deer Lodge County was founded in 1864, formed from Idaho County and Missoula County.

What is the county seat of Deer Lodge County?

The county seat of Deer Lodge County is Anaconda.

Is there an online parcel map for Deer Lodge County?

Yes. A public source publishes a parcel map of 7,719 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Deer Lodge County's boundary or name changed?

Deer Lodge County was created in 1864 from Idaho County and Missoula County. Since then the Atlas of Historical County Boundaries records 21 later changes, chiefly involving Jefferson County, Madison County and Silver Bow County.

Is my lot in a flood zone?

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

County · code 30023

Deer Lodge CountyMontana

Deer Lodge County is a county in Montana with its seat in Anaconda. The county was founded on January 16, 1864.

Founded1864
County seatAnaconda
Land area737 sq mi + 4.7 sq mi water
Population9,421 2020 Census
Parcels mapped7,719 checked 14 October 2026

Open the free map Click any parcel in Deer Lodge 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 Idaho County and Missoula County

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

Deer Lodge was created by Idaho Territory from Idaho, Missoula County, and non-county area. It became a Montana Territory county on May 26, 1864. In May 1977, the city of Anaconda and Deer Lodge County formed a consolidated city/county government while retaining the county name.

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

1864
Deer Lodge County created Deer Lodge created by Idaho Territory from Idaho (Idaho), Missoula, and non-county area.
from Idahofrom Missoula
16 January 1864 · Idaho Terr. Laws 1863, 1st sess., sec. 2/pp. 674-675
1864
Became part of Montana Deer Lodge became a county in Montana Territory. On 22 September 1864, Montana Territorial Governor, Sidney Edgerton, recognized the counties created by Idaho Territory in an election proclamation. 26 May 1864 · U.S. Stat., vol. 13, ch. 95 [1864], sec. 1/pp. 85-92; Sanders, Helen F., 1:329; Van Zandt, 145
1865
Deer Lodge County created Deer Lodge re-created by Montana Territory; Deer Lodge gained from Beaverhead, Jefferson, and Madison.
from Beaverhead from Jefferson from Madison
2 February 1865 · Mont. Terr. Laws 1864, 1st leg., sec. 2/p. 529
1889
Became part of Montana Deer Lodge became a county in the state of Montana. 8 November 1889 · U.S. Stat., vol. 26, pp. 1551-1552 and vol. 25, ch. 180 [1889]/pp. 676-684; Swindler, 6:82-83
c. 1977
Eliminated The city of Anaconda and the county of Deer Lodge formed a consolidated city/county government, but the county retained the name, Deer Lodge. 31 May 1977 · Deer Lodge County, http://rad.dli.state.mt.us/county/deerldg, 2 July 2004

Show all 24 changes (19 more)

1864
Deer Lodge County created Deer Lodge created by Idaho Territory from Idaho (Idaho), Missoula, and non-county area.
from Idahofrom Missoula
16 January 1864 · Idaho Terr. Laws 1863, 1st sess., sec. 2/pp. 674-675
1864
Became part of Montana Deer Lodge became a county in Montana Territory. On 22 September 1864, Montana Territorial Governor, Sidney Edgerton, recognized the counties created by Idaho Territory in an election proclamation. 26 May 1864 · U.S. Stat., vol. 13, ch. 95 [1864], sec. 1/pp. 85-92; Sanders, Helen F., 1:329; Van Zandt, 145
1865
Deer Lodge County created Deer Lodge re-created by Montana Territory; Deer Lodge gained from Beaverhead, Jefferson, and Madison.
from Beaverhead from Jefferson from Madison
2 February 1865 · Mont. Terr. Laws 1864, 1st leg., sec. 2/p. 529
1867
Exchanged territory Deer Lodge exchanged with Missoula.
with Missoula
20 November 1867 · Mont. Terr. Laws 1867, 4th leg., pp. 105-106
1867
Lost territory Deer Lodge lost to Edgerton (now Lewis and Clark).
to Edgertonto Lewis and Clark
21 November 1867 · Mont. Terr. Laws 1867, 4th leg., p. 101
1867
Lost territory Deer Lodge lost to Jefferson.
to Jefferson
2 December 1867 · Mont. Terr. Laws 1867, 4th leg., pp. 104-105
1867
Boundary clarified Deer Lodge boundaries redefined (no change).
no change
10 December 1867 · Mont. Terr. Laws 1867, 4th leg., sec. 1/p. 102
1867
Lost territory Deer Lodge lost to Madison.
to Madison
23 December 1867 · Mont. Terr. Laws 1867, 4th leg., pp. 129-130
1869
Lost territory Deer Lodge lost to Madison.
to Madison
12 January 1869 · Mont. Terr. Laws 1868, 5th leg., p. 105
1872
Exchanged territory Deer Lodge exchanged with Beaverhead.
with Beaverhead
12 January 1872 · Mont. Terr. Laws 1871, 7th leg., ch. 20, secs. 2-3/pp. 429-430
1876
Lost territory Deer Lodge lost to Choteau (now Chouteau).
to Choteauto Chouteau
5 February 1876 · Mont. Terr. Laws 1876, 9th leg., pp. 46-47
1881
Lost territory Deer Lodge lost to creation of Silver Bow; Silver Bow not fully organized, attached to Deer Lodge "for judicial purposes."
to Silver Bow
16 February 1881 · Mont. Terr. Laws 1881, 12th leg., pp. 85-88
1881
Changed Silver Bow fully organized, detached from Deer Lodge.
Silver Bow
1 May 1881 · Mont. Terr. Laws 1881, 12th leg., sec. 11/p. 88
1887
Boundary clarified Deer Lodge boundaries redefined (no change).
no change
1 March 1887 · Mont. Terr. Laws 1887, 15th leg., secs. 731, 741/pp. 833-834, 838-839
1889
Became part of Montana Deer Lodge became a county in the state of Montana. 8 November 1889 · U.S. Stat., vol. 26, pp. 1551-1552 and vol. 25, ch. 180 [1889]/pp. 676-684; Swindler, 6:82-83
1891
Exchanged territory Deer Lodge exchanged with Jefferson.
with Jefferson
5 March 1891 · Mont. Laws 1891, 2d leg., pp. 224-225
1893
Lost territory Deer Lodge lost to creation of Granite.
to Granite
2 March 1893 · Mont. Laws 1893, 3d leg., pp. 212-217
1899
Lost territory Deer Lodge lost to Flathead.
to Flathead
6 March 1899 · Mont. Laws 1899, 6th leg., p. 47
1899
Lost territory Deer Lodge lost to Lewis and Clark. Act passed 28 February 1899; took effect 1 June 1899.
to Lewis and Clark
1 June 1899 · Mont. Laws 1899, 6th leg., pp. 44-47
1901
Lost territory Deer Lodge lost to creation of Powell.
to Powell
1 February 1901 · Mont. Laws 1901, 7th leg., pp. 101-106
1901
Changed Legislature authorized Deer Lodge to be renamed Daly, and Powell to be renamed Deer Lodge; change did not take effect. Montana Supreme Court ruled against the name change on 8 April 1901.
DalyPowell
8 March 1901 · Mont. Laws 1901, 7th leg., pp. 107-110; "State ex rel. Sackett v. Thomas," in Mont. Rpts., 25:226-241
1903
Gained territory Deer Lodge gained from Silver Bow, exchanged with Jefferson. Act passed 4 March 1903; took effect 15 June 1903.
from Silver Bow from Jefferson
15 June 1903 · Mont. Laws 1903, 8th leg., ch. 62/pp. 127-130
1917
Lost territory Deer Lodge lost to Silver Bow. Act passed 13 February 1917; took effect 1 May 1917.
to Silver Bow.
1 May 1917 · Mont. Laws 1917, 15th leg., ch. 21/pp. 22-24
c. 1977
Eliminated The city of Anaconda and the county of Deer Lodge formed a consolidated city/county government, but the county retained the name, Deer Lodge. 31 May 1977 · Deer Lodge County, http://rad.dli.state.mt.us/county/deerldg, 2 July 2004

Land and parcels

What the maps cover in Deer Lodge

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

Parcels Good enough

Lot lines and tax-map numbers for 7,719 parcels. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 14 October 2026
Address points Official

One point per address, 6,522 in all from Montana State Library.
edited 13 October 2026 · checked 14 October 2026
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

Deer Lodge by the Census

Population

9,421 2020 Census count

Housing units

5,493 2020 Census count

Land area

737 square miles

Water area

4.7 square miles

People per sq mi

13 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

Deer Lodge 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 Deer Lodge County.
anacondadeerlodge.mt.gov

See your own lot on these maps

Open Deer Lodge 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 Deer Lodge County

When was Deer Lodge County founded?: Deer Lodge County was founded in 1864, formed from Idaho County and Missoula County.
What is the county seat of Deer Lodge County?: The county seat of Deer Lodge County is Anaconda.
Is there an online parcel map for Deer Lodge County?: Yes. A public source publishes a parcel map of 7,719 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Deer Lodge County's boundary or name changed?: Deer Lodge County was created in 1864 from Idaho County and Missoula County. Since then the Atlas of Historical County Boundaries records 21 later changes, chiefly involving Jefferson County, Madison County and Silver Bow County.
Is my lot in a flood zone?: We do not have flood maps for Deer Lodge County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby