Cook County Value

122 William St Northlake, IL 60164

3 bed / 1 bath, 1,106 sqft, built 1949, in Leyden. Assessor market value for 2026: $230,380.

Cook County account 12324050150000

Assessor market value
$230,380
Tax year 2026 · before exemptions; the assessed value on your notice is 10% of it
Living area
1,106 sqft
$208 per sqft
Year built
1949
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 60164 and Leyden assessment pages.

Local guide: Leyden Township 2026 Property Tax Appeal Guide.

Appeal deadlines

For Leyden, appeals to the Assessor closed . Board of Review dates for Leyden 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 stayed about the same, from $230,380 in 2025 to $230,380 in 2026.
  • Assessor market value per square footThe current public record shows about $208 per square foot before any comparable-property adjustments.
  • Nearby comparison areaThis page starts the equity review with public records for the Leyden neighborhood and ZIP 60164.
  • Neighborhood value signalAmong 4,819 residential records in the same neighborhood, the average assessor market value is about $208 per square foot.
  • Area year-over-year signalNearby residential records with prior-year values moved about -0.9% on average.

Comparable assessments

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

  • 210 Whitehall Dr Northlake, IL 60164
    1,111 sqft | $216/sqft | built 1948 | Similar size (1,111 vs 1,106 sqft); Similar age (1948 vs 1949); Similar lot size (7,500 vs 7,500 sqft)
    $240,000
  • 201 Whitehall Dr Northlake, IL 60164
    1,114 sqft | $219/sqft | built 1950 | Similar size (1,114 vs 1,106 sqft); Similar age (1950 vs 1949); Similar lot size (7,500 vs 7,500 sqft)
    $243,440
  • 272 E Dickens Ave Northlake, IL 60164
    1,098 sqft | $228/sqft | built 1948 | Similar size (1,098 vs 1,106 sqft); Similar age (1948 vs 1949); Similar lot size (7,500 vs 7,500 sqft)
    $250,000
  • 137 N Marilyn Ave Northlake, IL 60164
    1,097 sqft | $219/sqft | built 1950 | Similar size (1,097 vs 1,106 sqft); Similar age (1950 vs 1949); Similar lot size (7,500 vs 7,500 sqft)
    $240,000
  • 26 Bernice Dr Northlake, IL 60164
    1,096 sqft | $219/sqft | built 1948 | Similar size (1,096 vs 1,106 sqft); Similar age (1948 vs 1949); Similar lot size (7,500 vs 7,500 sqft)
    $240,000

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: . 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

No change in 2026 from 2025.

Assessor market value by tax year, with the change from the previous year listed
Tax yearAssessor market valueChangeChange %
2026$230,380$00.0%
2025$230,380+$30,380+15.2%
2024$200,000$00.0%
2023$200,000$00.0%
2022$200,000+$56,700+39.6%
2021$143,300$00.0%
2020$143,300——
6-year total+$87,080+60.8%