Cook County Assessor First-Pass Property Values for 2019

Cook County Assessor's Office created this dataset of first-pass property values for 2019 residential assessments. The data was archived on February 14, 2020 and is no longer updated. It contains 17 columns, including PIN, Property Address, Most Recent Sale Price, and multiple First Pass Value estimates.

Use Cases

• Analyze the relationship between Most Recent Sale Price and First Pass Value estimates using PIN and First Pass Value columns.
• Compare preliminary land and building valuations by joining Estimate (Land) and Estimate (Building) with Land Value and Improvement Value.
• Identify properties with specific sale characteristics by filtering on Deed No., Most Recent Date Sale, and Pure Market Indicator.
• Map property assessment data by geocoding Property Address and linking to PIN for spatial analysis.

Strengths

• Data originates from the authoritative Cook County Assessor's Office Computer Assisted Mass Appraisal system.
• Dataset provides 17 distinct columns covering property identifiers, addresses, sale history, and multiple valuation estimates.
• Available in multiple machine-readable formats including CSV, JSON, XML, and RDF.

Limitations

• Dataset was archived in February 2020 and is explicitly stated as no longer updated, limiting its current applicability.
• Row count and total data size are unknown, which may complicate suitability assessment for large-scale projects.
• Values are first-pass estimates and are explicitly noted as NOT final assessed values, requiring caution in interpretation.

Provenance

Source

Cook County Assessor's Office via datacatalog.cookcountyil.gov.

Collection Method

Generated from the Assessor's Computer Assisted Mass Appraisal system for residential property assessment.

Time Range

2019 assessment year; dataset archived February 2020.

Freshness

Last updated 2026-01-27 20:14:59; however, the data content was archived and frozen as of February 14, 2020.

Geography

Cook County, Illinois, United States.