Cook County Value

123 S Harold Ave Northlake, IL 60164

2 bed / 1 bath, 861 sqft, built 1950, in Proviso Assessor market value for 2026: $270,000.

Cook County account 15051170100000

Assessor market value
$270,000
Tax year 2026 · before exemptions; the assessed value on your notice is 10% of it
Living area
861 sqft
$314 per sqft
Year built
1950
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 Proviso assessment pages.

Local guide: Proviso Township 2026 Property Tax Appeal Guide.

Appeal deadlines

For Proviso, appeals to the Assessor are open through (8 days left).

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 42.1% from $190,000 in 2025 to $270,000 in 2026.
  • Assessor market value per square footThe current public record shows about $314 per square foot before any comparable-property adjustments.
  • Nearby comparison areaThis page starts the equity review with public records for the Proviso neighborhood and ZIP 60164.
  • Neighborhood value signalAmong 630 residential records in the same neighborhood, the average assessor market value is about $204 per square foot.
  • Area year-over-year signalNearby residential records with prior-year values moved about +15.7% on average.

Comparable assessments

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

  • 115 S Roy Ave Northlake, IL 60164
    846 sqft | $284/sqft | built 1943 | Similar size (846 vs 861 sqft); Similar lot size (7,500 vs 7,500 sqft); Same quality (Average)
    $240,000
  • 136 S Roy Ave Northlake, IL 60164
    900 sqft | $233/sqft | built 1949 | Similar size (900 vs 861 sqft); Similar age (1949 vs 1950); Similar lot size (7,500 vs 7,500 sqft)
    $210,000
  • 117 S Harold Ave Northlake, IL 60164
    870 sqft | $276/sqft | built 1939 | Similar size (870 vs 861 sqft); Similar lot size (7,500 vs 7,500 sqft); Same quality (Average)
    $240,000
  • 138 S Prater Ave Northlake, IL 60164
    924 sqft | $238/sqft | built 1948 | 7% larger (924 vs 861 sqft); Similar age (1948 vs 1950); Similar lot size (7,500 vs 7,500 sqft)
    $220,000
  • 108 S Harold Ave Northlake, IL 60164
    900 sqft | $267/sqft | built 1955 | Similar size (900 vs 861 sqft); Similar age (1955 vs 1950); Similar lot size (7,700 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

Up 42.1% in 2026 from 2025.

Assessor market value by tax year, with the change from the previous year listed
Tax yearAssessor market valueChangeChange %
2026$270,000+$80,000+42.1%
2025$190,000$00.0%
2024$190,000$00.0%
2023$190,000+$49,540+35.3%
2022$140,460$00.0%
2021$140,460+$100.0%
2020$140,450——
6-year total+$129,550+92.2%