Parcel Chartplaces Open the free map

County · code 42119

Union CountyPennsylvania

Union County is a county in Pennsylvania with a seat in Lewisburg. It was created in 1813 and named after the United States.

  • Founded1813
  • County seatLewisburg
  • Named forUnited States
  • Land area316 sq mi + 1.8 sq mi water
  • Population42,681 2020 Census
  • Parcels mapped20,405 checked 15 October 2026
Open the free map Click any parcel in Union County: acreage, parcel id, address and who publishes the map. No sign-in.

Updated

SnyderNorthumberlandLycomingClintonMifflinCentre Lewisburg Census outline · seat marked

Where it is

Union on the map of Pennsylvania

Pennsylvania has 67 counties and county equivalents, each with its own records office. Shapes with a page are links.

Adams CountyAllegheny CountyArmstrong CountyBeaver CountyBedford CountyBerks CountyBlair CountyBradford CountyBucks CountyButler CountyCambria CountyCameron CountyCarbon CountyCentre CountyChester CountyClarion CountyClearfield CountyClinton CountyColumbia CountyCrawford CountyCumberland CountyDauphin CountyDelaware CountyElk CountyErie CountyFayette CountyForest CountyFranklin CountyFulton CountyGreene CountyHuntingdon CountyIndiana CountyJefferson CountyJuniata CountyLackawanna CountyLancaster CountyLawrence CountyLebanon CountyLehigh CountyLuzerne CountyLycoming CountyMcKean CountyMercer CountyMifflin CountyMonroe CountyMontgomery CountyMontour CountyNorthampton CountyNorthumberland CountyPerry CountyPhiladelphia CountyPike CountyPotter CountySchuylkill CountySnyder CountySomerset CountySullivan CountySusquehanna CountyTioga CountyVenango CountyWarren CountyWashington CountyWayne CountyWestmoreland CountyWyoming CountyYork CountyUnion County Union
Counties of Pennsylvania · Union highlighted

History

Formed in 1813 from Northumberland County

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

Union was created from Northumberland in 1813. Over the following decades, Union exchanged land with neighboring counties, losing territory to Lycoming and Centre, and gaining territory from Mifflin, Lycoming, and the new county of Snyder.

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

  1. 1813
    Union County created Union created from Northumberland.
    from Northumberland
    · Pa. Laws 1812-1813, ch. 110, secs. 1-2/p. 150
  2. 1815
    Lost territory Union lost to Lycoming.
    to Lycoming
    · Pa. Laws 1814-1815, ch. 79, sec. 1/p. 119
  3. 1819
    Gained territory Union gained from Mifflin.
    from Mifflin
    · Pa. Laws 1818-1819, ch. 77, sec. 1/pp. 111-112
  4. 1820
    Lost territory Union lost to Centre.
    to Centre
    · Pa. Laws 1819-1820, ch. 120, sec. 2/pp. 176-177; Linn, 34, 60-61
  5. 1855
    Lost territory Union lost to the creation of Snyder.
    to Snyder
    · Pa. Laws 1855, no. 555, secs. 1, 7/pp. 537-538
Show all 8 changes (3 more)
  1. 1813
    Union County created Union created from Northumberland.
    from Northumberland
    · Pa. Laws 1812-1813, ch. 110, secs. 1-2/p. 150
  2. 1815
    Lost territory Union lost to Lycoming.
    to Lycoming
    · Pa. Laws 1814-1815, ch. 79, sec. 1/p. 119
  3. 1819
    Gained territory Union gained from Mifflin.
    from Mifflin
    · Pa. Laws 1818-1819, ch. 77, sec. 1/pp. 111-112
  4. 1820
    Lost territory Union lost to Centre.
    to Centre
    · Pa. Laws 1819-1820, ch. 120, sec. 2/pp. 176-177; Linn, 34, 60-61
  5. 1832
    Boundary clarified Boundary between Union and Lycoming redefined (no change).
    with Lycomingno change
    · Pa. Laws 1831-1832, no. 175, secs. 21, 24/pp. 457-458
  6. 1855
    Lost territory Union lost to the creation of Snyder.
    to Snyder
    · Pa. Laws 1855, no. 555, secs. 1, 7/pp. 537-538
  7. 1861
    Gained territory Union gained from Lycoming.
    from Lycoming
    · Pa. Laws 1861, no. 317, sec. 1/p. 335
  8. 1868
    Gained territory Union gained from Lycoming.
    from Lycoming
    · Pa. Laws 1868, no. 486, secs. 1-2/p. 526

Land and parcels

What the maps cover in Union

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

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

Union by the Census

Population
42,681 2020 Census count
Housing units
16,082 2020 Census count
Land area
316 square miles
Water area
1.8 square miles
People per sq mi
135 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

Union County's official site

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

County government

See your own lot on these maps

Open Union 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 Union County

When was Union County founded?
Union County was founded in 1813, formed from Northumberland County, and named after United States.
What is the county seat of Union County?
The county seat of Union County is Lewisburg.
Is there an online parcel map for Union County?
Yes. Union County publishes a parcel map of 20,405 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Union County's boundary or name changed?
Union County was created in 1813 from Northumberland County. Since then the Atlas of Historical County Boundaries records 6 later changes, chiefly involving Lycoming County, Centre County and Mifflin County.
Is my lot in a flood zone?
We do not have flood maps for Union County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby

Counties next door