Illinois · FIPS 17099 · County seat: Ottawa

LaSalle County, IL GIS & Parcel Viewer

Looking for lot lines or a parcel number in LaSalle County, IL? The quickest route is LaSalle County, IL, the county parcel map we keep on file for this county. We link straight to it and add a few tips for getting around.

Open the LaSalle County parcel map ↗
Opens gis.lasallecounty.org in a new tab. We link out and never embed or copy parcel data.

LaSalle County at a glance

Official map	LaSalle County, IL
Type	County-run map
Website	gis.lasallecounty.org
Access	Free, no login (checked Oct 2026)
County seat	Ottawa
Population	108,309 (2023 Census Bureau estimate)
Land area	1,135 sq mi
FIPS code	17099

Who runs this map

This map is published by or for LaSalle County itself, so it reflects the local parcel layer rather than a third-party copy. When we tested the link in October 2026 it opened with no login and no fee.

Searching for a parcel, step by step

Press the button above to open the county's own web map.
Search for the property or pan and zoom to it.
Click the lot to bring up what the county publishes about it.
Look for print or measure tools if you need a quick map or rough size.

Many parcel sites expect owner names last name first. If a full name finds nothing, try just the surname.

LaSalle County by the numbers

Census Bureau figures put LaSalle County at about 108,309 people (2023 estimate) on roughly 1,135 square miles of land, which is about 95 residents per square mile. Among Illinois's 102 counties, it is the 17th largest by population. The county seat is Ottawa.

Counties next to LaSalle County

If the property sits near a county line, the parcel may belong to a neighbor. These counties border LaSalle County:

A note on accuracy

Treat the map as a guide, not a boundary survey: parcel outlines are often shifted a bit from the real corners. A licensed surveyor settles exact lines.

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