Cook County Value

510 N May St, Chicago, IL 60642

20 bed / 6 bath, 8,896 sqft, built 1878, in Jefferson. Assessor market value for 2026: $1,640,000.

Cook County account 17082370270000

Assessor market value
$1,640,000
Tax year 2026 · before exemptions; the assessed value on your notice is 10% of it
Living area
8,896 sqft
$184 per sqft
Year built
1878
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 60642 and Jefferson assessment pages.

Local guide: West Chicago Township 2026 Property Tax Appeal Guide.

Appeal deadlines

For West Chicago, appeals to the Assessor closed . Board of Review dates for West Chicago 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 $1,640,000 in 2025 to $1,640,000 in 2026.
  • Assessor market value per square footThe current public record shows about $184 per square foot before any comparable-property adjustments.
  • Nearby comparison areaThis page starts the equity review with public records for the Jefferson neighborhood and ZIP 60642.
  • Neighborhood value signalAmong 3,753 residential records in the same neighborhood, the average assessor market value is about $356 per square foot.
  • Area year-over-year signalNearby residential records with prior-year values stayed about flat on average.

Comparable assessments

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

  • 1222 N Noble St, Chicago, IL 60642
    8,625 sqft | $175/sqft | built 1887 | Similar size (8,625 vs 8,896 sqft); Similar lot size (2,937 vs 2,784 sqft); Same quality (Average)
    $1,513,420
  • 1460 W Chicago Ave, Chicago, IL 60642
    9,662 sqft | $164/sqft | built 1883 | 9% larger (9,662 vs 8,896 sqft); Similar age (1883 vs 1878); Similar lot size (2,856 vs 2,784 sqft)
    $1,580,000
  • 1323 W Huron St, Chicago, IL 60642
    7,920 sqft | $188/sqft | built 1878 | 11% smaller (7,920 vs 8,896 sqft); Built same year (1878); Similar lot size (2,640 vs 2,784 sqft)
    $1,490,000
  • 1123 W Grand Ave, Chicago, IL 60642
    7,680 sqft | $172/sqft | built 1881 | 14% smaller (7,680 vs 8,896 sqft); Similar age (1881 vs 1878); Similar lot size (2,750 vs 2,784 sqft)
    $1,318,490
  • 1460 W Cortez St, Chicago, IL 60642
    7,874 sqft | $179/sqft | built 1878 | 12% smaller (7,874 vs 8,896 sqft); Built same year (1878); Similar lot size (2,976 vs 2,784 sqft)
    $1,410,680

Recent comparable sales

No usable comparable sales are available in this data snapshot.

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

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$1,640,000$00.0%
2025$1,640,000$00.0%
2024$1,640,000−$220,000−11.8%
2023$1,860,000$00.0%
2022$1,860,000$00.0%
2021$1,860,000+$1,004,460+117.4%
2020$855,540——
6-year total+$784,460+91.7%