Cook County Value

605 William St River Forest, IL 60305

4 bed / 1 bath, 2,280 sqft, built 1914, in River Forest. Assessor market value for 2026: $852,680.

Cook County account 15122090080000

Assessor market value
$852,680
Tax year 2026 · before exemptions; the assessed value on your notice is 10% of it
Living area
2,280 sqft
$374 per sqft
Year built
1914
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 60305 and River Forest assessment pages.

Local guide: River Forest Township 2026 Property Tax Appeal Guide.

Appeal deadlines

The 2026 appeal windows for River Forest have closed (Assessor , Board of Review ). 2027 notices usually start in March.

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 38.2% from $616,810 in 2025 to $852,680 in 2026.
  • Assessor market value per square footThe current public record shows about $374 per square foot before any comparable-property adjustments.
  • Nearby comparison areaThis page starts the equity review with public records for the River Forest neighborhood and ZIP 60305.
  • Neighborhood value signalAmong 637 residential records in the same neighborhood, the average assessor market value is about $380 per square foot.
  • Area year-over-year signalNearby residential records with prior-year values moved about +29.4% on average.

Comparable assessments

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

  • 604 Clinton Pl River Forest, IL 60305
    2,226 sqft | $382/sqft | built 1909 | Similar size (2,226 vs 2,280 sqft); Similar age (1909 vs 1914); Similar lot size (6,512 vs 6,512 sqft)
    $850,000
  • 601 Forest Ave River Forest, IL 60305
    2,294 sqft | $366/sqft | built 1918 | Similar size (2,294 vs 2,280 sqft); Similar age (1918 vs 1914); Similar lot size (7,160 vs 6,512 sqft)
    $840,000
  • 736 Ashland Ave River Forest, IL 60305
    2,161 sqft | $303/sqft | built 1915 | 5% smaller (2,161 vs 2,280 sqft); Similar age (1915 vs 1914); Similar lot size (5,887 vs 6,512 sqft)
    $655,020
  • 610 Park Ave River Forest, IL 60305
    2,165 sqft | $351/sqft | built 1915 | 5% smaller (2,165 vs 2,280 sqft); Similar age (1915 vs 1914); Lot 11% larger (7,240 vs 6,512 sqft)
    $760,000
  • 606 Park Ave River Forest, IL 60305
    2,226 sqft | $364/sqft | built 1916 | Similar size (2,226 vs 2,280 sqft); Similar age (1916 vs 1914); Lot 11% larger (7,240 vs 6,512 sqft)
    $810,000

Recent comparable sales

Sales selected by similarity to the subject property.

Public appraisal comparison for 2026. Prepared . Appraisal source: Cook County Assessor's Office. Sales data checked in this snapshot: . Matches consider available size, age, location and property characteristics. How comparisons work.

Value history

Up 38.2% in 2026 from 2025.

Assessor market value by tax year, with the change from the previous year listed
Tax yearAssessor market valueChangeChange %
2026$852,680+$235,870+38.2%
2025$616,810−$40,920−6.2%
2024$657,730$00.0%
2023$657,730+$158,820+31.8%
2022$498,910−$20,520−4.0%
2021$519,430−$40,010−7.2%
2020$559,440——
6-year total+$293,240+52.4%