When was Warren County founded?

Warren County was founded in 1824, formed from Sussex County, and named after Joseph Warren.

What is the county seat of Warren County?

The county seat of Warren County is Belvidere.

Is there an online parcel map for Warren County?

Yes. A public source publishes a parcel map of 48,873 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.

Has Warren County's boundary or name changed?

Warren County was created in 1824 from Sussex County. The Atlas of Historical County Boundaries records no boundary change since.

Is my lot in a flood zone?

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

County · code 34041

Warren CountyNew Jersey

Warren County is in New Jersey and has its seat in Belvidere. The county was formed in 1824 from Sussex County and was named after Joseph Warren.

Founded1824
County seatBelvidere
Named forJoseph Warren
Land area357 sq mi + 6.1 sq mi water
Population109,632 2020 Census
Parcels mapped48,873 checked 15 October 2026

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

Updated 19 October 2026

Census outline · seat marked

History

Formed in 1824 from Sussex County

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

Warren County was created on November 20, 1824, from Sussex County.

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

1824
Warren County created Warren created from Sussex.
from Sussex
20 November 1824 · N.J. Acts 1824, pp. 146-147; Snyder, 36

Land and parcels

What the maps cover in Warren

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

Parcels Good enough

Lot lines and tax-map numbers for 48,873 parcels. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 15 October 2026
Address points Official

One point per address, 50,116 in all from NJOGIS.
edited 23 September 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

Warren by the Census

Population

109,632 2020 Census count

Housing units

46,457 2020 Census count

Land area

357 square miles

Water area

6.1 square miles

People per sq mi

307 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

Warren 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 Warren County.
co.warren.nj.us

See your own lot on these maps

Open Warren 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 Warren County

When was Warren County founded?: Warren County was founded in 1824, formed from Sussex County, and named after Joseph Warren.
What is the county seat of Warren County?: The county seat of Warren County is Belvidere.
Is there an online parcel map for Warren County?: Yes. A public source publishes a parcel map of 48,873 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
Has Warren County's boundary or name changed?: Warren County was created in 1824 from Sussex County. The Atlas of Historical County Boundaries records no boundary change since.
Is my lot in a flood zone?: We do not have flood maps for Warren County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.

Nearby