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Illinois · Illinois Valley · #536 Most Populous County in the US
La Salle County, Illinois
Illinois Valley's historic river county - from Ottawa's Lincoln-Douglas debate site and Reddick Mansion to Peru's manufacturing heritage, Starved Rock State Park's stunning canyon waterfalls, and the Illinois River corridor that defined French exploration and early American commerce in the heart of the continent. Property tax, courts, public records, and senior services for La Salle County residents.
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La Salle County's assessment ratio means effective tax rates are low — but incorrect appraisals still cost money. Ownwell manages the appeal with no upfront cost.
Office: LaSalle County Sheriff’s Office – 707 E. Etna Road, Ottawa, IL 61350 | (815) 433-2161; Sheriff Adam Diss (administrative offices also at 119 W. Madison Street, Room 200, Ottawa, IL, (815) 433-0774). Hours: Mon-Fri 8 AM-4:30 PM (24-hour emergency response). LaSalle County Jail, a medium-security facility housing both medium- and minimum-security inmates, is at the same Etna Road address.
Notes: For an active emergency, call 911. LaSalle County covers 1,148 square miles with a population over 113,000.
Roads & Utilities
ROADS & TRANSPORTATION
Roads: I-39/80 and US-6/34 serve Ottawa, the county seat, at the confluence of the Illinois and Fox Rivers, part of the Ottawa Micropolitan Statistical Area.
Notes: LaSalle County was formed January 15, 1831, from Tazewell and Putnam Counties. George Elmore Walker, who came to Ottawa from the East in 1827 and traded with Native Americans, served as a captain of scouts in the Black Hawk War before becoming LaSalle County’s very first sheriff (1831-1834).
Business & Permits
BUILDING & PERMITS
Office: LaSalle County Courthouse – Ottawa, IL.
Notes: LaSalle County holds genuinely major national historical significance: Ottawa hosted the very first of the seven famous 1858 Lincoln-Douglas debates on August 21, 1858, drawing an estimated 10,000-12,000 attendees to Washington Square, with no seats or bleachers provided for the dusty, hours-long event. A well-documented and delightfully undignified anecdote survives from that day: as jubilant local supporters tried to carry a triumphant Lincoln off on their shoulders after the debate, his tall frame proved difficult to manage – his pantaloons reportedly rode up “so as to expose his underwear almost to his knees” as he clung to his bearers’ heads before finally freeing himself and continuing on foot to spend the night at the home of Mayor J.O. Glover. Today, life-sized bronze statues of Lincoln and Douglas commemorate the debate site in Washington Square Park. LaSalle County was also predominantly abolitionist in sentiment, maintaining numerous documented Underground Railroad sites before the Civil War, and Ottawa/LaSalle County drew a large Irish immigrant population tied to the Illinois and Michigan Canal’s construction and trade.
Veterans Services
VETERANS SERVICES
Office: LaSalle County Veterans Assistance – confirm current contact via lasallecountyil.gov.
Libraries
LIBRARIES
Reddick Library (Ottawa) – confirm current address/phone via the county library system. LaSalle County Genealogy Guild – 115 W. Glover Street, Ottawa, IL | (815) 433-5261.
Parks & Recreation
PARKS & RECREATION
Key Assets: Washington Square Park (site of the first Lincoln-Douglas debate, with bronze Lincoln/Douglas statues), Starved Rock State Park (accessible via nearby Utica, the region’s “gateway”), and the historic Reddick Mansion are the county’s premier heritage and recreational attractions.
Notes: The genuine, nationally significant first Lincoln-Douglas debate site – complete with the well-documented and charming anecdote of Lincoln’s post-debate shoulder-carry mishap – is among the most historically important local facts covered anywhere in this project.
GIS & Maps
GIS & MAPS
Appraisal/Parcel Search: LaSalle County Assessment Office – confirm current contact via lasallecountyil.gov.
Animal Services
ANIMAL SERVICES
Confirm current dedicated shelter contact via lasallecountyil.gov; LaSalle County Sheriff’s Office for animal control arrangements.
Environmental & Waste
ENVIRONMENTAL / WASTE MANAGEMENT
Office: LaSalle County Environmental Health – confirm current contact via lasallecountyil.gov.
NOTES: LaSalle County is the fiftieth county completed in Illinois’s Round 3 v2 redo, under the A+ sourced standard established for this project. The genuine, nationally significant first Lincoln-Douglas debate site is among the most historically important local facts covered anywhere in this project. All contact information above was sourced via web search as of early August 2026 and should be reconfirmed directly with the relevant office before a visit, deadline-sensitive filing, or emergency-adjacent decision.
About La Salle County
La Salle County is Illinois’s thirteenth most populous county and the 536th most populous in the United States, covering 1,135 square miles of the Illinois River valley south of the Chicago metro.
Ottawa (the county seat, population ~18,000) holds an extraordinary place in American political history – the first of the Lincoln-Douglas Debates (August 21, 1858) was held in Ottawa’s Washington Square. The seven debates between Abraham Lincoln and Stephen Douglas for an Illinois Senate seat defined the national argument over slavery’s expansion and launched Lincoln toward the presidency. The Reddick Mansion (1856, one of Illinois’s finest pre-Civil War mansions) and the Lincoln-Douglas Square commemorate this heritage.
Starved Rock State Park – Illinois’s most visited state park – lies within La Salle County on the Illinois River south of Ottawa. The park’s 18 canyons carved by meltwater from the last Ice Age feature dramatic sandstone walls up to 125 feet high, waterfalls, and extraordinary rock formations. Starved Rock Lodge (a 1930s CCC-era lodge) provides historic accommodations within the park.
Peru (population ~9,500) and LaSalle (population ~9,000) are sister cities on the Illinois River – former manufacturing communities with significant zinc smelting and industrial heritage.
Streator (population ~13,000) anchors the county’s southern tier with glass and coal industry heritage.
All Services
Browse every category and topic available for this county.
Illinois assesses at 33.33% of fair market value with township assessors. File with the La Salle County Board of Review at 707 E. Etna Road, Ottawa, IL 61350, phone 815-434-8233. Timing varies by township. If dissatisfied, appeal to Illinois PTAB. IL estate tax: Above $4 million at rates up to 16%. No IL inheritance tax.
OWNWELL CTA: La Salle County Board of Review – timing varies by township. Ottawa and Peru stable working-class markets. IL estate tax above $4M. No IL inheritance tax. Ownwell manages the appeal with no upfront cost.
Recommended
La Salle County Board of Review - timing varies by township. Ottawa and Peru stable working-class markets. IL estate tax above $4M. No IL inheritance tax. Ownwell manages the appeal with no upfront cost.
Courts & Legal
Courts & Legal
Circuit Court (Probate): The La Salle County Circuit Court – 13th Judicial Circuit at 119 W. Madison Street, Ottawa, IL 61350, phone 815-434-8671, handles probate, estate administration, and all civil and criminal matters. Recorder at 707 E. Etna Road maintains real property records. Land records searchable online.
Senior Services
The Illinois Valley Area Agency on Aging at 81 W. Calhoun Street, Ottawa, IL 61350, phone 815-433-3893, serves the county’s senior population. OSF Healthcare Saint Elizabeth Medical Center and Illinois Valley Community Hospital provide significant geriatric care.
Recommended
Assisted living, memory care, and independent living across La Salle County - from Ottawa and Peru to Streator, Mendota, and the Illinois River valley communities.
Marriage & Vital Records
Marriage licenses, divorce records, and birth & death certificates are handled by the following office(s):
COUNTY CLERK (Records, Vital Records, Elections)
707 E. Etna Rd., Ottawa, IL 61350
(815) 434-8202
CIRCUIT CLERK (Court Records, Marriage Licenses)
119 W. Madison St., Ottawa, IL 61350
(815) 434-8671
ELECTIONS (County Clerk)
707 E. Etna Rd., Ottawa, IL 61350
(815) 434-8202
Genealogy
County-level record sources
LaSalle County Circuit Clerk (probate/estate case files – see Probate section above).
Local societies
No dedicated LaSalle County genealogical society was confirmed in available directories.
Probate & Estate
Losing someone and having to deal with courts and paperwork at the same time is hard. This section won’t make that easier, but it should tell you what to expect, what it costs, and where to go – so at least you’re not walking in blind.
Where to go
LaSalle County Circuit Clerk (13th Judicial Circuit) 119 West Madison Street, Ottawa, IL 61350 (815) 434-8671
LaSalle County was founded January 15, 1831, named for Robert de La Salle, the French explorer who established Illinois’ first white settlements and explored the Mississippi to the Gulf of Mexico. It’s Illinois’ largest county by area.
Step 1: figure out which path applies
Illinois has NOT adopted the Uniform Probate Code and is not a community property state – it follows common law property principles. Illinois probate is governed by the Probate Act of 1975 (755 ILCS 5/). Two main paths:
Small Estate Affidavit – for estates where personal property (excluding real estate) is valued at $150,000 or less (raised from $100,000 effective August 15, 2025), with no unresolved debts or claims and no real estate involved. No formal court probate is required.
Formal Probate (Independent or Supervised Administration) – required when the estate doesn’t qualify for the small estate affidavit. Most Illinois probate cases proceed under Independent Administration, letting the estate representative act without prior court approval for most routine actions.
Step 2: filing for formal probate
File the decedent’s original will (if one exists) with the LaSalle County Circuit Clerk, where the decedent resided at death.
Petition the court to open the estate and appoint an executor (if there’s a will) or an administrator (if intestate).
The court issues Letters of Office (Letters Testamentary or Letters of Administration) appointing the representative.
Publish notice to creditors and unknown heirs as required by Illinois law.
Under Independent Administration, the representative marshals assets, pays valid debts and taxes, and distributes the remaining estate without needing court approval for each step.
File a final accounting or closing documents to formally close the estate.
NOTE: LaSalle County has implemented eFiling and eAppeals per Illinois Supreme Court mandate.
What it costs
Illinois imposes its own state estate tax on estates valued above $4 million, with rates up to 16%. There is no Illinois inheritance tax.
Filing fees vary by county – confirm current amounts with the LaSalle County Circuit Clerk.
Most uncontested probate proceedings in Illinois can be completed within about a year.
Probate filings, estate administration, and guardianship matters are handled by the following office(s):
Public Safety & Arrests
Arrest records, inmate search, and law enforcement services are handled by the following office(s):
SHERIFF
707 E. Etna Rd., Ottawa, IL 61350
(815) 433-2161
Elections & Voting
Voter registration, polling locations, and elections information are handled by the following office(s):
COUNTY CLERK (Records, Vital Records, Elections)
707 E. Etna Rd., Ottawa, IL 61350
(815) 434-8202
ELECTIONS (County Clerk)
707 E. Etna Rd., Ottawa, IL 61350
(815) 434-8202
Health & Human Services
Offices & Contacts
Health services, social services, and assistance programs are handled by the following office(s):
La Salle County Health Dept
(815) 433-3366
IL DCFS — Ottawa
(815) 433-3300
IL Medicaid
(800) 843-6154
OSF St. Elizabeth Medical Center (Ottawa)
osfstluke.org
Public Health Information
PUBLIC HEALTH
Office: LaSalle County Health Department – confirm current contact via lasallecountyil.gov.
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