Counties / Illinois / Warren County

Warren County, IL

FIPS 17187 · population 16,447 · outside every metro area

$115k
Zillow home value · 2026-06
The numbers

What this county costs and earns

Everything here joins on the county FIPS code, so each figure comes from the agency that publishes it with no name matching in between.

Zillow home value
$115k
▼ 0.5% year over year
Zillow ZHVI · direct
ACS median gross rent
$788
occupied-unit survey; not current asking rent
Census ACS · surveyed
Gross yield
n/a
gross yield cannot be computed without measured market rent
requires both measured price and measured rent
HUD 2-bed standard
$916
the Section 8 payment standard
HUD Fair Market Rent · direct
Independent price check

Do two methods point the same way?

Zillow estimates a current home value. FHFA tracks repeat mortgage transactions. Their growth rates should be read side by side, not averaged.

The annual signals disagree
FHFA five-year cumulative+26.9%not annualized · through 2025
0%ZILLOW ZHVI2026-06−0.5%FHFA HPI2025+5.2%
Annual changes use different methods and may use different periods. The comparison checks direction and magnitude; it does not create a blended estimate. Zillow county ZHVI pulled 2026-07-26; FHFA annual county HPI pulled 2026-07-28.
Owner-reported value$105k
Surveyed gross rent$788
Rent burden 30%+35.1%
Median year built1956
Housing composition

Who occupies the stock—and what it is

ACS 2024 5-year
10.5%vacant
7,587estimated housing units
Occupied tenure24.8% renter
owner 75.2%renter 24.8%
Structure mix88.1% single-family
Single-family 88.1%20+ units 2.3%Mobile home 2.6%Other 7.0%
ACS estimates describe the standing housing stock and occupied tenure. They do not measure current listings, transaction prices or asking rents.

Survey source: Census ACS 5-year — county housing value, tenure and stock · ACS 2024 5-year · pulled 2026-07-30. These values describe different housing universes and are not combined into gross yield.

Annual average covered jobs6,351▼ 0.3% from the prior annual release
Covered establishments366annual average reporting locations
Average weekly wage$889▲ 1.6% from the prior annual release
Largest private supersectorManufacturing35.7% of disclosed private covered jobs
Local labor base

Jobs, pay and private-sector concentration

2025
0%COVERED JOBS−0.3%WEEKLY WAGE+1.6%Manufacturing35.7%
Annual QCEW counts cover jobs located at reporting establishments. The industry share uses disclosed private covered employment; it is not a resident-employment measure or a forecast.

Workplace source: BLS QCEW — county employment and wages · annual county employment and wages 2025 vs 2024 · pulled 2026-07-31. QCEW counts covered jobs located in the county, not employed residents or the metro score’s CES/LAUS series.

County brief

What the local evidence says

01Decision frame

Warren County’s decision tension is mixed price evidence alongside unmeasured income. Yield-focused buyers should be cautious until subject rents and operating costs are documented; operators willing to test individual locations have a reason to investigate. Zillow’s June 2026 median home value was $114,979, down 0.46% year over year. FHFA’s annual 2025 repeat-transaction HPI, which is not a home value, gained 5.17% year over year and 26.87% over five years. These different methods and vintages cannot be merged into a single appreciation reading.

02Housing economics

No county market asking rent is published, so gross yield cannot be computed. HUD’s two-bedroom FMR is $916 per month, a payment standard rather than an estimate of asking rent, and cannot substitute in that calculation. The effective property-tax rate is 1.81%, warranting parcel-level confirmation. This price-and-carrying-cost evidence does not establish a cap rate, cash flow, or affordability.

03Demand & competition

Realtor.com’s June 2026 MLS market had higher year-over-year median asking prices, a 67-day median marketing time, and 15.92% of listings reduced. These are listing-market evidence: median listing price is an asking price, active listings are visible supply, days on market measure marketing time, and reductions indicate seller concessions; none is a closed-sale price or proof of buyer demand on its own. Tax-return migration adds a separate caution: out-movers exceeded in-movers, and average AGI for entrants was lower than for leavers. Non-occupant borrowers accounted for 12% of 100 purchase mortgages, which does not identify cash buyers or tenant demand. QCEW’s annual 2025 county-workplace series showed covered employment edging down and average weekly wages rising; Manufacturing was the largest disclosed private supersector, not the whole economy.

04Risk & next checks

Inland flood is the dominant hazard, and the modeled annual climate-loss ratio is 0.15% of building value. That is a county-level expected-loss model, not a property insurance quote or measured loss; flood-zone, elevation, coverage, deductible, and mitigation records are needed. Missing market rents prevent yield and debt-service testing; missing closed-sale comparables prevent purchase-value confirmation; and missing parcel hazard and insurance evidence prevent a complete carrying-cost assessment. County evidence cannot resolve condition, tenancy, vacancy, or neighborhood liquidity.

Cities & communities

Where people live within Warren County

Census-recognized incorporated places and CDPs that intersect this county. The list does not pretend to include every neighborhood or informal community.

Population scale

Largest Census places

ACS 2024 5-year
Monmouth city8.6KRoseville village823Alexis village*814Kirkwood village754Avon village*694Little York village379Cameron CDP280
Bars use total place population, not a county-share estimate. An asterisk marks a place that crosses a county line.
Official directory

7 Census places

Population
  1. 01
    Monmouth cityIncorporated place
    8,581
  2. 02
    Roseville villageIncorporated place
    823
  3. 03
    Alexis villageIncorporated place · spans 2 counties
    814
  4. 04
    Kirkwood villageIncorporated place
    754
  5. 05
    Avon villageIncorporated place · spans 2 counties
    694
  6. 06
    Little York villageIncorporated place
    379
  7. 07
    Cameron CDPCensus-designated place
    280

Population is the total place-wide ACS estimate, not an allocated county share. A place crossing a county line is labelled explicitly. Source: Census ACS 5-year — cities and communities · ACS 2024 5-year · pulled 2026-07-30.

Risk, demand and competition

The three things a price does not tell you

01
Risk & carrying costFEMA NRI + Census ACS
Dominant hazardinland flooding

0.154% of building value expected lost per year

Effective property tax1.81%

$1,903 median annual bill

02
DemandIRS SOI household flows
Net migration-96

318 in · 414 out

Arriving vs leaving income−$2,124

$45,654 arriving · $47,778 leaving

03
CompetitionHMDA financed purchases
Purchases by investors12.0%

12 of 100 mortgages

investorother financed
Current listing pressure

What sellers and visible supply are doing

Realtor.com® Economic Research · county inventory 2026-06 · pulled 2026-07-28
Active listings51▲ 4.1% year over year
Median days on market67▲ 17.1% year over year
Listings price-reduced15.9%seller-concession signal
Median listing pricen/a▲ 9.5% year over year

Listing price is an asking price, not a closed sale. Quality-flagged county rows are withheld instead of displayed.

No rent index is published for this county.Zillow’s county rent series does not cover every county, and estimating one from a neighbouring county would be a guess wearing a number’s clothes. Everything above is measured here; no wider market is mapped for it either.
Bear case

What can break the county thesis

  1. No published market rent leaves yield and debt-service capacity untested.
  2. MLS listing evidence lacks closed-sale comparables, so acquisition value may differ from visible asking prices.
  3. County-level inland-flood modeling cannot establish a subject property's insurance, mitigation, or exposure costs.
Underwriting questions

Before pricing a property

Can gross yield be calculated from this record?

No. County market rent is not published, and HUD FMR is a payment standard rather than market asking rent.

What is the largest disclosed private supersector?

Manufacturing. This identifies the largest disclosed private supersector in QCEW covered county-workplace employment, not the entire economy.

What hazard needs parcel-level review?

Inland flood. The record provides a county-level modeled climate-loss ratio, not property-specific insurance terms or measured losses.