Cook County Value

1131 Gillian St Lemont, IL 60439

4 bed / 2 bath, 2,651 sqft, built 1994, in Lemont. Assessor market value for 2026: $580,000.

Cook County account 22294190040000

Assessor market value
$580,000
Tax year 2026 · before exemptions; the assessed value on your notice is 10% of it
Living area
2,651 sqft
$219 per sqft
Year built
1994
Average quality

Compare this assessment

Start with the county value and property facts, then review appraisal comps, recent sales, and prior-year changes to decide whether the assessment is worth challenging. The comps on this page are free to review; email sign-in is only used to save a printable report.

For nearby context, browse ZIP 60439 and Lemont assessment pages.

Local guide: Lemont Township 2026 Property Tax Appeal Guide.

Appeal deadlines

For Lemont, appeals to the Assessor closed . Board of Review dates for Lemont have not been published yet.

Deadline rule: Set by township: file with the Assessor by your township's last file date, and with the Board of Review while your township is open there. Evidence is reviewed by the Cook County Assessor's Office or, in a separate appeal, by the Cook County Board of Review. Dates checked against the official source.

Assessment snapshot

These public CCAO records highlight what may be worth checking before you file.

  • Assessment changeThe assessor market value increased 35.0% from $429,700 in 2025 to $580,000 in 2026.
  • Assessor market value per square footThe current public record shows about $219 per square foot before any comparable-property adjustments.
  • Nearby comparison areaThis page starts the equity review with public records for the Lemont neighborhood and ZIP 60439.
  • Neighborhood value signalAmong 858 residential records in the same neighborhood, the average assessor market value is about $264 per square foot.
  • Area year-over-year signalNearby residential records with prior-year values moved about +21.4% on average.

Comparable assessments

Similar public appraisal records selected for this property's equity comparison.

  • 526 Keepataw Dr Lemont, IL 60439
    2,567 sqft | $214/sqft | built 1996 | Similar size (2,567 vs 2,651 sqft); Similar age (1996 vs 1994); Similar lot size (8,296 vs 8,520 sqft)
    $550,000
  • 1130 Glenys Dr Lemont, IL 60439
    2,650 sqft | $208/sqft | built 1985 | Similar size (2,650 vs 2,651 sqft); Similar lot size (8,750 vs 8,520 sqft); Same quality (Average)
    $550,000
  • 512 Keepataw Dr Lemont, IL 60439
    2,685 sqft | $201/sqft | built 1985 | Similar size (2,685 vs 2,651 sqft); Similar lot size (8,400 vs 8,520 sqft); Same quality (Average)
    $540,000
  • 509 Keepataw Dr Lemont, IL 60439
    2,463 sqft | $211/sqft | built 1989 | 7% smaller (2,463 vs 2,651 sqft); Similar age (1989 vs 1994); Similar lot size (9,000 vs 8,520 sqft)
    $520,000
  • 510 4th St Lemont, IL 60439
    2,657 sqft | $237/sqft | built 2005 | Similar size (2,657 vs 2,651 sqft); Lot 15% larger (9,834 vs 8,520 sqft); Same quality (Average)
    $630,000

Recent comparable sales

Sales selected by similarity to the subject property.

  • 1238 Acorn St Lemont, IL 60439
    2,802 sqft | $223/sqft | built 1990 | 6% size difference (2,802 sqft); Moderate age difference (4 years older); Within 1 bedroom (3 vs 4)
    $625,000
  • 11 Cedar Ct Lemont, IL 60439
    2,722 sqft | $253/sqft | built 1990 | Similar size (2,722 sqft); Moderate age difference (4 years older); Same beds (4)
    $690,000

Public appraisal comparison for 2026. Prepared . Appraisal source: Cook County Assessor's Office. Sales data checked in this snapshot: . Showing the last prepared sales evidence while recent sales are refreshed. Matches consider available size, age, location and property characteristics. How comparisons work.

Value history

Up 35.0% in 2026 from 2025.

Assessor market value by tax year, with the change from the previous year listed
Tax yearAssessor market valueChangeChange %
2026$580,000+$150,300+35.0%
2025$429,700$00.0%
2024$429,700−$60,300−12.3%
2023$490,000+$205,590+72.3%
2022$284,410$00.0%
2021$284,410−$14,910−5.0%
2020$299,320——
6-year total+$280,680+93.8%