When was Lycoming County founded?

Lycoming County was founded in 1795, formed from Northumberland County, and named after Lycoming Creek, Pennsylvania.

What is the county seat of Lycoming County?

The county seat of Lycoming County is Williamsport.

Is there an online parcel map for Lycoming County?

Yes. Lycoming County publishes a parcel map of 51,439 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Lycoming County's boundary or name changed?

Lycoming County was created in 1795 from Northumberland County. Since then the Atlas of Historical County Boundaries records 21 later changes, chiefly involving Centre County, Bradford County and Clinton County.

Is my lot in a flood zone?

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

County · code 42081

Lycoming CountyPennsylvania

Lycoming County is a county in Pennsylvania with its seat in Williamsport. The county was created on April 13, 1795, from Northumberland County and named after Lycoming Creek.

Founded1795
County seatWilliamsport
Named forLycoming Creek, Pennsylvania
Land area1,229 sq mi + 15 sq mi water
Population114,188 2020 Census
Parcels mapped51,439 checked 16 October 2026

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

Updated 19 October 2026

Census outline · seat marked

History

Formed in 1795 from Northumberland County

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

Lycoming County was created from Northumberland County in 1795 and quickly lost territory to the creation of Centre, Armstrong, Venango, Warren, and Indiana counties. Over the following two decades, the county's boundaries shifted through the creation of Clearfield, Jefferson, McKean, Potter, and Tioga counties, with Potter and Tioga initially attached to Lycoming, and Bradford later replacing Ontario. By 1818, Lycoming had reached approximately its current boundaries after losing territory to Centre County.

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

1795
Lycoming County created Lycoming created from Northumberland.
from Northumberland
13 April 1795 · Pa. Stat., ch. 1834, sec. 1/15:288
1800
Lost territory Lycoming lost to the creation of Centre.
to Centre
13 February 1800 · Pa. Stat., ch. 2103, sec. 1/16:403
1800
Lost territory Lycoming lost to the creation of Armstrong, Venango, and Warren.
to Armstrong to Venango to Warren
12 March 1800 · Pa. Stat., ch. 2130, pp. 458-461
1803
Lost territory Lycoming lost to the creation of Indiana.
to Indiana
30 March 1803 · Pa. Stat., ch. 2374, secs. 1, 3/17:434-435
1804
Lost territory Lycoming lost to the creation of Clearfield, Jefferson, McKean, Potter, and Tioga; Potter and Tioga attached to Lycoming.
to Clearfield to Jefferson to McKean to Potter to Tioga
26 March 1804 · Pa. Stat., ch. 2478, pp. 769-771, 774

Show all 24 changes (19 more)

1795
Lycoming County created Lycoming created from Northumberland.
from Northumberland
13 April 1795 · Pa. Stat., ch. 1834, sec. 1/15:288
1800
Lost territory Lycoming lost to the creation of Centre.
to Centre
13 February 1800 · Pa. Stat., ch. 2103, sec. 1/16:403
1800
Lost territory Lycoming lost to the creation of Armstrong, Venango, and Warren.
to Armstrong to Venango to Warren
12 March 1800 · Pa. Stat., ch. 2130, pp. 458-461
1803
Lost territory Lycoming lost to the creation of Indiana.
to Indiana
30 March 1803 · Pa. Stat., ch. 2374, secs. 1, 3/17:434-435
1804
Lost territory Lycoming lost to the creation of Clearfield, Jefferson, McKean, Potter, and Tioga; Potter and Tioga attached to Lycoming.
to Clearfield to Jefferson to McKean to Potter to Tioga
26 March 1804 · Pa. Stat., ch. 2478, pp. 769-771, 774
1804
Gained territory Lycoming gained from Luzerne.
from Luzerne
2 April 1804 · Pa. Stat., ch. 2506, sec. 1/17:846-847
1810
Lost territory Lycoming lost to the creation of Ontario (now Bradford) and gained small area from Luzerne; Ontario (now Bradford) attached to Lycoming.
to Ontario to Bradfordto Luzerne
21 February 1810 · Pa. Laws 1809-1810, ch. 30, secs. 1, 3/pp. 32-33
1812
Changed Bradford and Tioga detached from Lycoming.
Bradford Tioga
13 October 1812 · Pa. Laws 1811-1812, ch. 109, sec. 2/p. 164
1815
Lost territory Lycoming lost to Luzerne.
to Luzerne
21 February 1815 · Pa. Laws 1814-1815, ch. 35, sec. 1/pp. 43-44
1815
Gained territory Lycoming gained from Union.
from Union
1 May 1815 · Pa. Laws 1814-1815, ch. 79, sec. 1/p. 119
1815
Changed McKean attached to Lycoming.
McKean
1 September 1815 · Pa. Laws 1813-1814, ch. 116, sec. 1/p. 201
1818
Lost territory Lycoming lost to Centre.
to Centre
1 May 1818 · Pa. Laws 1817-1818, ch. 139, sec. 1/p. 263
1819
Gained territory Lycoming gained from Centre.
from Centre
1 May 1819 · Pa. Laws 1818-1819, ch. 118, sec. 1/p. 185
1823
Lost territory Lycoming lost to Clearfield.
to Clearfield
1 April 1823 · Pa. Laws 1822-1823, ch. 174, sec. 1/p. 289
1826
Changed McKean and Potter detached from Lycoming.
McKean Potter
1 September 1826 · Pa. Laws 1823-1824, ch. 65, secs. 1, 8/pp. 104, 106
1831
Gained territory Lycoming gained from Bradford.
from Bradford
1 May 1831 · Meginness, 271; Pa. Laws 1828-1829, no. 115, sec. 1/p. 144; Pa. Laws 1830-1831, no. 83, sec. 1/p. 133
1832
Boundary clarified Boundary between Lycoming and Union redefined (no change).
with Unionno change
4 May 1832 · Pa. Laws 1831-1832, no. 175, secs. 21, 24/pp. 457-458
1836
Exchanged territory Lycoming exchanged with Centre.
with Centre
25 May 1836 · Pa. Laws 1835-1836, no. 160, sec. 10/p. 511
1839
Lost territory Lycoming lost to the creation of Clinton.
to Clinton
21 June 1839 · Pa. Laws 1838-1839, no. 145, sec. 1/p. 362
1848
Lost territory Lycoming lost to the creation of Sullivan.
to Sullivan
3 January 1848 · Pa. Laws 1847, no. 365, secs. 1-2/p. 462
1861
Lost territory Lycoming lost to Union.
to Union
17 April 1861 · Pa. Laws 1861, no. 317, sec. 1/p. 335
1867
Gained territory Lycoming gained from Clinton.
from Clinton
2 August 1867 · Lycoming County Road Docket, 1859-1868, vol. 6, p. 530
1868
Lost territory Lycoming lost to Clinton and Union.
to Clinton to Union
31 March 1868 · Pa. Laws 1868, no. 486, secs. 1-2/p. 526
1900
Boundary clarified Boundary between Lycoming and Tioga clarified (no change).
with Tiogano change
7 September 1900 · "Commissioners' Report and Map (linen tracing), 1888." Pa. State Arch., Land Office Recs., no. 53, item 27

Land and parcels

What the maps cover in Lycoming

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

Parcels Good enough

Lot lines and tax-map numbers for 51,439 parcels from Lycoming County. 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 Lycoming 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

Lycoming by the Census

Population

114,188 2020 Census count

Housing units

52,625 2020 Census count

Land area

1,229 square miles

Water area

15 square miles

People per sq mi

93 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.

Zoning and code

Zoning Permitsfrom lycomingcountypa.gov

County government

County government
The official website of Lycoming County.
lyco.org

See your own lot on these maps

Open Lycoming 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 Lycoming County

When was Lycoming County founded?: Lycoming County was founded in 1795, formed from Northumberland County, and named after Lycoming Creek, Pennsylvania.
What is the county seat of Lycoming County?: The county seat of Lycoming County is Williamsport.
Is there an online parcel map for Lycoming County?: Yes. Lycoming County publishes a parcel map of 51,439 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Lycoming County's boundary or name changed?: Lycoming County was created in 1795 from Northumberland County. Since then the Atlas of Historical County Boundaries records 21 later changes, chiefly involving Centre County, Bradford County and Clinton County.
Is my lot in a flood zone?: We do not have flood maps for Lycoming County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby